Moog Minitmoog 300A, Satellite 5330 Owner's Service Manual

MANUAL

NO.

993-041990-002

OWNERS

and

SERVICE

MANUAL

for

nnaoq

MINITMOOG/

SATELLITE

Minitmoog
Model

300A

Satellite

Model

5330

Introduction

The

owners

portion

of

this

manual,

pages 1 through

11,

provides

introductory

material

to

familiarize

the

owner

with

the

features,

specifications

and

initial

set-up

of

the

Minitmoog

Synthesizer,

Model

3Q0A,

and

the

Satellite

Synthesizer,

Model

5330.

The

technical

portion

of

this

manual,

pages

12

through

57,

provides

servicing,,

replacement

parts

list

and

illustrations

to

enable a qualified

technician

to

service

and

maintain

the

Minitmoog

and

Satellite

Synthesizers.

Index

MINITMOOG

SYNTHESIZER

CONTENTS

Controls

Quick-Set

Voice

Tabs

2

Modulation,

Oscillation

and

Touch

Controls

3

Slide

Control

Panel

4

Accessories

and

Connections

10

Care

of

Your

Synthesizer

11

Technical

Sections

12

SATELLITE

SYNTHESIZER

PAGE

CONTENTS

PAGE

Controls

5

Quick-Set

Voice

Tabs

6

Modulation

8

Slide

Control

Panel

9

Accessories

and

Connections

10

Care

of

Your

Synthesizer

11

Technical

Sections

12

THESE

DRAWINGS

AND

SPECIFICATIONS

ARE

THE

PROPERTY

OF

MOOG

MUSIC

INC.

AND

SHALL

NOT

BE

REPRODUCED

OR

COPIED

IN

WHOLE

OR

IN

PART

AS

THE

BASIS

FOR

MANUFACTURE

OR

SALE

OF

THE

ITEMS.

Minitmoog

Controls

SLIDE

CONTROLS

MODULATION

GLIDE

VOLUME

PANEL

CONTROLS

CONTROL CONTROL

SOLO

KEYBOARD

SYNC,

GLIDE

SUSTAIN

TABS

POWER

OFF-ON

SWITCH

INDICATOR

LIGHT

QUICK-SET

VOICING

TABS

FILTER

CONTROLS

TOUCH

SENSE

MODULATION

TABS

Before

proceeding

with

Operation

and

Adjustment

of

your

unit,

please

refer

to

page

10

for

Connection

Instructions.

LEVEL

ADJUST

M u . e „

This

rotary

control

(located

on

the

back

of

the

unit)

sets

the

overall

output

level,

or

volume,

of the

unit.

Smaller

changes

in

volume

may

be

made

with

the

VOLUME

control

on

the

Slide

Control

Panel.

This

rotary

control

(located

on

the

back

of the

unit)

provides

a

range

of

tuning

which

extends

more

than

one-half

octave.

This

flexibility

can

be

used

to

tune

your

MOOG

MINITMOOG

to

other

instruments,

transpose

to

different

keys,

or

even

provide a glissando

effect.

POWER

AND

INDICATOR

LIGHT

.

u

.

An

ON-OFF

power

switch

is

conveniently

located

on

the

front

panel,

with a red

light

which

indicates

when

the

power

is

ON.

OCTAVES

t

. . t

With

neither

tab

depressed,

your

MOOG

MINITMOOG

will

play

in

its

highest

pitch

level.

Depress

tab 1 ,

and

what

ever

you

play

on

the

keyboard

will

be

one

octave

lower.

Raise

tab

"1"

and

depress

tab

"2",

and

the

keyboard

pitch

level

is

lowered

another

octave.

Depress

both

tabs

and

the

pitch

level

is

lowered

still

a

third

octave.

Because

of

the

electronic

tailoring

of

the

sounds

to

the

requirements

of

each

pitch

level,

you

will

find

that the

effectiveness

of

every

sound

seems

to

change

magically

as

you

change

from

octave to

octave.

Try

all

sound

effects

in

all

four

pitch

levels.

SUSTAIN

. . .

This

"Quick-Set"

tab

allows

the

sound

of a note

to

"linger"

after

the

key

is

released.

It

provides

interesting

variations

to

the

special

voice

settings

described

in

this

Manual.

Minitmoog

Quick-Set

Voice

Tabs

TAURUS

GUITAR-1

VIOLIN

With

the

unit

connected

and

power

ON, a sound

can

be

heard

when a note

on

the

keyboard

is

struck,

even

though

no

voices

are

selected

and

all

slide

controls

are

set

at

"0"

(except

for

the

VOLUME

control).

The

controls

described

herein

will

add and

subtract

from

that

sound

in a multitude

of

combinations

available

for

your

exploration

-

shape

it,

change

its

attack

and

release,

raise

it,

or

lower

it.

We

suggest

that

you

play a phrase

or

two

with

each

of

the

twelve

"QUICK-SET"

VOICE

TABS

conveniently

located

on

the

front

of

the

unit.

Try

each

with

all

the

slide

controls

set

at

"0"

(except

for

VOLUME).

Exact

setting

of

slide

controls

for

any

particular

effect

will

depend,

not

only

on

your

musical

taste,

but

also

on

your

complete

electronic

reproduction

system

including

amplifiers,

speakers

and

other

components.

NOTE:

If

more

than

one

"QUICK-SET"

Voice

Tab

is

depressed

at

the

same

time

the

sound

will

be

that

controlled

by

the

Voice

Tab

farthest

to

the

left.

MUTE

This

voice

is a new

version

of

the

wah-wah

effect.

The

sound

approximates

a

double-acting

wah-wah,

or

"ooo-wah-ooo."

It

starts

with

an

emphasis

on

the

"lows",

moves

to

the

"highs"

and

returns.

Each

time a key

is

depressed

the

"ooo-wah-ooo"

sound

is

produced.

Try

it

in

each

octave.

TRUMPET

The

sounds

of a trumpet,

trombone,

or

tuba can

be

approximated

by

selecting

this

tab,

and

varying

it

with

other

controls.

Characteristic

of

this

voice

(and

some

of

the

other

"Quick-Set"

voices)

is a built-in

timbre

change

which

is

faster

in

the

upper

octaves

and

is

automatically

slower

in

the

lower

octaves

•

much

as

the attack

of a tuba

differs

from

that

of a trumpet.

This

attention to

the

authentic

details

of the

attack

in

different

octaves

is

a

unique

feature

of

the

Minitmoog.

Try

it

in

each

octave

setting.

OBOE

This

voice

provides

a

sound

similar

to

that

of a double

reed. In

the

top

octave

the

sound

is

oboe-like.

In

the

lower

octaves,

the

sound

of a bassoon

is

approximated.

You

will

note a slight

timbre

change

in

the

onset

of

the

tone

and a slow

attack.

CLARINET

The

hollow

reed

sound

and

the

soft

attack

of

the

traditional

clarinet

and

bass

clarinet

are

characteristic

of

this

voice -an

excellent

voice

in

all

octave

registers.

SAX

This

full

bodied

reed

sound

is

unique

to

the

Minitmoog.

It

combines

some

of

the

qualities

of a double

reed

wind

instrument

with

those

of a pipe

organ

with a little

sax

ophone

added.

In

the

lowest

registers,

it is

an

excellent

reproduction

of the

sound-

of

the

sarrusophone,

a

wind

instrument

popular

in

bands

of

the

early

1900's.

aa

we

TAURUS

This

voice

approximates

that

of a saxophone.

With

adjustment

of

other

controls

you

will

be

able

to vary

the

und

through

the

characteristics

of

alto

and

tenor,

bari-

ne,

and

bass

sounds

of

the

Taurus

Synthesizer.

VIOLIN

This

gentle

voice

with

its

slow

attack

can

be

made

to

simulate

violin,

viola,

cello,

and

even

some

of the

sounds

of

the

bass

violin.

GUITAR-1

This

sound

is

quite

percussive

with a lingering

decay.

It

is

most

useful

for

creating

guitar-like

or

harpsichord-

type

effects,

including

that

of a folk

guitar.

PIANO

In

the

upper

registers

this

voice

is

that

of

an

electronic

piano.

In

the

lower

registers

it

provides

an

interesting

sound

similar

to

that

of

an

electric

bass

guitar.

AIRES

Banjo

type

sounds

are

provided

with

the

hollow

sound

characteristic

of

this

voice.

In

the

lower

registers

it

can

simulate

the

plucked

sound

of

the

string

bass,

or

bass

violin.

GUITAR

-2

In

the

upper

octaves a fine

bell

sound

is

provided

by

this

voice.

In

the

lower

octaves,

the

huge

sound

of

a

large

carillon

can

be

reproduced.

LUNAR

This

versatile

voice

perhaps

is

most

characteristic

of

the

Moog

sounds.

It

provides,

in

its

various

adjust

ments, a wide

variety

of

timbre

changes

with

which

you

can

produce

many

popular

electronic

"Moog"

sound

effects.

It

is

most

effective

when

used

with

SUSTAIN.

Minitmoog

Modulation,

Oscillation

and

Touch

Controls

RATE

DEPTH

•B"

PITCH'

A/BMIX

TOUCH

SENSE

FILTER

TREMULANT

VIBRATO

MODULATION

The

two

function

tabs

labeled

MODULATION

on

the

front

of

the

unit

provide a selection

of

modulation

types.

The

two

MODULATION

slide

controls

on

the

slide

control

panel

adjust

the

RATE

and

DEPTH

of

modulation.

VIB

(VIBRATO)

This

tab

provides

a

frequency-modulation

vibrato

simi

lar

to

the

type used

in

electronic

organs.

However,

the

wide

range

of

effects

offered

by

the

two

slide

controls

extends

the

capability

of

this

effect

far

beyond

vibrato

and

into

the

realm

of

the

synthesizer.

When

the

VIB

tab

is

depressed,

the

basic

frequency

of a note

is

varied

(or

"wiggled")

to a degree

determined

by

the

DEPTH

control

and

at a rate

determined

by

the

RATE

control.

RATE

The

rate

of

modulation

may

be

varied

from

approx-

ately

one

second

at

"0"

to a rate

so

fast

that

at

10"

the

sound

becomes a buzz.

However,

even

at

ex

treme

settings,

the

basic

character

of

the

"QUICK-SET"

voices

is

still

apparent.

For

instance,

MUTE,

with

VIB

plus

RATE

at

10

becomes a BUZZ-WAH

type

of

effect.

With

slower

settings

it

is

easy

to

obtain

the

effect

of

trills

between

notes,

regardless

of the voice

selected.

DEPTH

This

control

adjusts

the degree

or

intensity

of

modu

lation.

For

vibrato

(VIB),

increasing

DEPTH

corresponds

to

greater

frequency

variation.

This

frequency

variation

may

be

adjusted

from

less

than

one-half

step

(on

the

scale)

to

more

than

one

octave.

For

tremulant

(TREM),

increasing

DEPTH

corresponds

to

greater

timbre

variation.

This

flexibility,

combined

with

the

RATE

control,

makes

possible

synthesis

of

such

effects

as

"out

of

tune"

strings,

huge

bells

whose

clanging

sounds

interfere

with

each

other,

quarter

tone

scales,

trumpet

"shake"

effects,

and a myriad

of

others.

TREM

(TREMULANT)

This

tab

provides

modulation

of

the

harmonic

content

of

the

tone.

The

harmonic

content,

or

timbre,

is

varied

at

a

rate

determined

by

the

RATE

control

and

with

an

intensity

determined

by

the

DEPTH

control.

NOTE:

VIB

and

TREM

can

be

used

together.

SYNC

This

tab

is

only

active

when

other

SYNC

tab

switch

is

also

down.

Raises

pitch

of B tone

osciliator as a key

is

depressed

harder

producing

a

phasing

effect.

PITCH

This

tab

bends

pitch

of

both A and B tone

oscillators

up

to

an

interval

of

at

least

seven

semitones

when a key

is

depressed

harder.

FILTER

This

tab

adds

familiar

Moog

"wah"

to

most

voices

when

pressure

on

the

keys

is

increased.

This

effect

adds

directly

to

the

effect

produced

by

the

FILTER

BRIGHT

NESS

slide

control.

MOD

This

tab

allows

either

vibrato

or

tremolo

to

be

added

to

the

tone

as

the

pressure

on

the

keys

is

increased.

The

DEPTH

slide

control

in

this

mode

acts

as a touch

sensitiv

ity

control

and

the

MODULATION

RATE

slide

control

sets

the

speed

of

the

effect.

This

tab

switch

has

an

effect

only

if

the

MODULATION

VIB

or

MODULATION

TREM

tab

switch

is

also

depressed.

TOUCH

SENSE

This

control

regulates

the

range

of

expressive

effects

when

additional

pressure

is

exerted

on

the

keys

for

SYNC,

PITCH

and

FILTER

(brightness)

modes.

"B"

PITCH

This

control

varies

pitch

ol B tone

producing

oscillator

over a two

octave

range.

A/B

MIX

Controls

mixing

of A and B tone source

oscillator

outputs. A only

or B only

occur

at

the

CCW

and

CW

extremes

of

rotation,

respectively.

Q

Minitmoog

Slide

Control

Panel

GLIDE

VOLUME

BRIGHTNESS

DECAY

ATTACK

FILTER

CONTROLS

u

.

.

Once a "Quick-Set"

tab

voice

selection

is

made,

further

refinement

and

adjustment

of

that

voice

may

be

made

oy

using

the

three

slide

controls

labeled

FILTER.

ATTACK

This

controls

the

speed

of

the

timbre

change

associated

with

the

onset

of

the

voice,

and/or

the

timbre

change

associated

with

the

release

of

that

voice.

The

wide

range

of

this

control

can

provide

both

slow

settings

(useful

for

simulation

of

bass

violin

or

tuba

effects)

and

fast

timbre

change

settings

(which can

provide

wild

chirping

effects).

DECAY

This

acts

as a brightness

control,

but

it

has

such

a

wide

range

that

it

can

have

major

effect

on

the

basic

sound

itself.

Your

choice

may

lie

anywhere

between

adding

in

all

of

the

high

harmonics

you

wish,

or

elim

inating

them.

BRIGHTNESS

This

control

adds a resonance

frequency

area

to

the

spectrum

of

the

tone.

At

"0",

spectrum

of the

"Quick-

Set"

sound

is

unchanged.

As

the

control

is

pushed

forward,

the

intensity

of

the

sound

within a pre-selected

resonance

area

is

increased.

At

maximum,

there

is a well

defined

narrow

sharp

peak

in

the

spectrum

of

the

tone.

FILTER

CONTROLS

SUMMARY

Remember,

the

"Quick-Set"

tabs

establish

an

overall

range

of

sound

and

the

three

Filter

slide

controls

give

you a wide

selection

and

control

within

the

limitations

of

that

range.

Try

this:

1.

Depress

TRUMPET

tab,

and

set

the

slide

controls

at

"0".

2.

Play a few

notes

on

the

keyboard.

3.

Play

again

with

various

settings

of

the

DECAY

slide

pot.

The

range

of

sound

will

be

from

that

of a very

dull

trumpet

to a very

brassy

one.

4.

Now

do

the

same

with

the

BRIGHTNESS

control.

The

sound

will

range

through

cornet,

trumpet,

and

flugelhorn

characteristics.

5.

Repeat

with

various

settings

of

the

ATTACK

control.

It

will

show

the

wide

range

of

contoured

timbers

in

the

onset

of

the

tones.

ADDITIONAL

CONTROLS

MODULATION

CONTROLS

See

discussion

under

MODULATION

on

page

3.

GLIDE

This

is

one

of

the

most

interesting

of

the

Moog

effects.

Depress

the

GLIDE

tab

and

set

the

GLIDE

slide

control

at

6.

Play

any

note

on

the

keyboard.

Release

this

note

and

quickly

play a second

note

some

distance

away.

The

sound

automatically

glissandos

from

the

first

note

to the

second.

The

setting

of

the

slide

control

determines

the

speed

of

the

glissando,

{10

is

slow -1

is

fast).

Try a melody

of

detached

notes

and

notice

the

succession

of

glide

attacks.

VOLUME

The

VOLUME

slide

control

provides

finger-tip

adjust

ment

of

fine

gradations

of

the

Minitmoog

output.

Major

changes

in

sound

level

are

obtained

by

means

of

the

rotary

knob

on

the

back

of

the

unit.

Satellite

Controls

SUOE

CONTROLS

PANEL

GLIDE

VOLUME

CONTROL CONTROL

LEVEL &

TUNE

CONTROLS

(LOCATED

ON

REAR

PANEL)

ACCESSORY & OUTPUT
CONNECTIONS

SOLO

(LOCATED

ON REAR

PANEL)

KEYBOARD

GLIDE,

SUSTAIN

TABS

Before

proceeding

with

Operation

and

Adjustment

of

your

unit,refer

to

page

10

for

Connection

Instructions.

LEVEL

ADJUST

This

rotary

control

(located

on

the

back

of

the

uniOsets

the

overall

output

level,

or

volume,

of

the

unit.

Smaller

changes

in

volume

may

be

made

with

the

VOLUME

control

on

the

Slide

Control

Panel.

\

TUNE

This

rotary

control

(located

on

the

back

of

the

unit)

provides

a

range

of

tuning

which

extends

more

than

one-half

octave.

This

flexibility

can

be

used

to

tune

your

MOOG

SATELLITE

to

other

instruments,

transpose

to

different

keys,

or

even

provide

a

glissando

effect.

POWER

AND

INDICATOR

LIGHT

An

ON-OFF

power

switch

is

conveniently

located

on

the

front

panel,

with

a

red

light

which

indicates

when

the

power

is

ON.

OCTAVES

With

neither

tab

depressed,

your

MOOG

SATELLITE

will

play

in

its

highest

pitch

level.

Depress

tab

"V,

and

whatever

you

play

on

the

keyboard

will

be

one

octave

lower.

Raise

tab

"1"

and

depress

tab

"2",

and

the

keyboard

pitch

level

is

lowered

another octave.

Depress

both

tabs

and

the pitch

level

is

lowered

still

a

third

octave.

Because

of

the

electronic

tailoring

of

the

sounds

to

the

requirements

of

each

pitch

level,

you

will

find

that

the

effectiveness

of

every

sound

seems

to

change

magically

as

you

change

from

octave

to

octave.

Try

all

sound

effects

in

all

four

pitch

levels.

SUSTAIN

This

"Quick-Set"

tab

allows

the

sound

of

a

note

to

"linger"

after

the

key

is

released.

It

pro

vides

interesting

variations

to

the

special

voice

settings

described

in

this

Manual.

Satellite

Quick-Set

Voice

Tabs

BRASS

VOICES'

•MUTE

•

OPEN

REED

VOICES

•THIN

•HOLLOW

•

FULL

•

BRIGHT

STRING VOICES

•BOW

•

PLUCK

•STRIKE

•

PICK

BELL

With

the

unit

connected

and

power

ON, a sound

can

be

heard

when a note

on

the

keyboard

is

stiuck.

even

though no

voices

are

selected

and

all

slide

controls

are set

at

"0"

(except

for

the

VOLUME

control

i.

The

controls

described

herein

will

add and

subtract

from

that

sound

in a multitude

of

combinations

<iv.ii

Lib

k*

tor

your

exploration

-

shape

it,

change

its

attack

and

release,

raise

it,

or

lower

it.

We

suggest

Unit

you

play a phrase

or

two

with

each

of

the

twelve

"QUICK-SET"

VOICE

TABS

conveniently

located

on

the

front

ol

ihc

unit.

Try

each

with

all

the

slide

controls

set

at

"0"

(except

for

VOLUME).

Exact

setting

of

slide

controls

for

any

particular

effect

will

depend,

not

only

on

your

musical

taste,

but

also

on

your

complete

electronic

reproduction

system

including

amplifiers,

speakers

and

other

components.

NOTE:

If

more

than

one

"QUICK-SET"

Voice

Tab

is

depressed

at

the

same

time

the

sound

will

be

that

controlled

by

the

Voice

Tab

farthest

to

the

left.

MUTE

BRASS

This

voice

is a new

version

of

the

wah-wah

effect.

The sound

approximates

a

double-acting

wah-wah,

.or

"ooowah-ooo."

It

starts

with

an

emphasis

on

the

"lows",

moves

to

the

"highs"

and

returns.

Each

time

a

key

is

depressed

the

"ooo-wah-ooo"

sound

is

pro

duced.

Try

it

in

each

octave.

OPEN

BRASS

The

sounds

of a trumpet,

trombone,

or

tuba

can

be

approximated

by

selecting

this

tab,

and

varying

it

with

other

controls.

Characteristic

of

this

voice

(and

some

of

the

other

"Quick-Set"

voices)

is a built-in

timbre

change

which

is

faster

in

the

upper

octaves

and

is

automatically

slower

in

the

lower

octaves

—

much

as

the

attack

of a tuba

differs

from

that

of

a

trumpet.

This

attention

to

the

authentic

details

of

the

attack

in

different

octaves

is a unique

feature

of

the

Satellite.

Try

it

in

each

octave

setting.

THIN

REED

This

voice

provides a sound

similar

to

that

of

a

double

reed.

In

the

top

octave

the

sound

is

oboe-like.

In

the

lower

octaves,

the

sound

of a bassoon

is

approximated.

You

will

note a slight

timbre

change

in

the

onset

of

the

tone

and a slow

attack.

HOLLOW

REED

The

hollow

reed

sound

and

the

soft

attack

of

the

raditional

clarinet

and

bass

clarinet

are

character

istic

of

this

voice -an

excellent

voice

in all

octave

registers.

FULL REED

This

full

bodied

reed

sound

is

unique

to

the

Satellite.

It

combines

some

of

the

qualities

of

a

double

reed

wind

instrument

with

those

of a pipe

organ

with a little

saxophone

added.

In

the

lowest

registers,

it

is

an

excellent

reproduction

of

the

sound

of

the

sarrusophone,

a

wind

instrument

popular

in

bands

of

the

early

1900's.

BRIGHT

REED

This

voice

approximates

that

of a saxophone.

With

adjustment

of

other

controls

you

will

be

able

to

vary

the

sound

through

the

characteristics

of

alto

and

tenor,

baritone,

and

even

bass

saxophone.

BOW

STRING

This

gentle

voice

with

its

slow

attack

can

be

made

to

simulate

violin,

viola,

cello,

and

even

some

of

the

sounds

of

the

bass

violin.

PLUCK

STRING

This

sound

is

quite

percussive

with a lingering

decay.

It

is

most

useful

for

creating

guitar-like

or

harpsichord-type

effects,

including

that

of

a folk

guitar.

STRIKE

STRING

In

the

upper

registers

this

voice

is

that

of

an

electronic

piano.

In

the

lower

registers

it

provides

an

interesting

sound

similar

to

that

of

an

electric

bass

guitar.

PICK

STRING

Banjo

type

sounds

are

provided

with

the

hollow

sound

characteristic

of

this

voice.

In

the

lower

registers

it

can

simulate

the

plucked

sound

of

the

string

bass,

or

bass

violin.

BELL

In

the

upper

octaves a fine

bell

sound

is

provided

by

this

voice.

In

the

lower

octaves,

the

huge

sound

of a large

carillon

can

be

reproduced.

LUNAR

This

versatile

voice

perhaps

is

most

characteris

tic

of

the

Moog

sounds.

It

provides,

in

its

various

adjustments,

a

wide

variety

of

timbre

changes

with

which

you

can

produce

many

popular

electronic

"Moog"

sound

effects.

It

is

most

effective

when

used

with

SUSTAIN.

Satellite

Modulation

RATE—'

DEPTH

Tfrf

REPEAT-*

UTREMULANT

' I VIBRATO

The

four

function

tabs

labeled

MODULATION

on

the

front

of

the

unit

provide a selection

of

modulation

types.

The

two

MODULATION

slide

controls

on

the

slide

control

panel

adjust

the

RATE

and

DEPTH

of

modulation.

VIB

(VIBRATO)

This

tab

provides a frequency-modulation

vibrato

similar

to

the

type

used

in

electronic

organs.

However,

the

wide

range

of

effects

offered

by

the

two

slide

controls

extends

the

capability

of

this

effect

far

beyond

vibrato

and

into

the

realm

of

the

synthesizer.

When

the

VIB

tab

is

depressed,

the

basic

frequency

of a note

is

varied

(or

"wiggled")

to a degree

deter

mined

by

the

DEPTH

control

and

at a rate

determined

by

the

RATE

control.

RATE

The

rate

of

modulation

may

be

varied

from

approx

imately

one second

at

"0"

to

a rate

so

fast

that

at

"10"

the

sound

becomes a buzz.

However, even

at

extreme

settings,

the

basic

character

of

the

"QUICK

SET"

voices

is

still

apparent.

For

instance,

MUTE

BRASS,

with

VIB

plus

RATE

at

10

becomes a BUZZ-WAH

type

of

effect.

With

slower

settings

it

is

easy

to

obtain

the

effect

of

trills

between

notes,

regardless

of

the

voice

selected.

DEPTH

This

control

adjusts

the

degree

or

intensity

of

modulation.

For

vibrato

(VIB),

increasing

DEPTH

corresponds

to

greater

frequency

variation.

This

frequency

variation

may

be

adjusted

from

less

than

one-half

step

(on

the

scale)

to

more

than

one

octave.

For

tremulant

(TREM),

increasing

DEPTH

corresponds

to

greater

timbre

variation.

This

flexibility,

combined

with

the

RATE

control,

makes

possible

synthesis

of

such

effects

as

"out

of

tune"

strings,

huge

bells

whose

clanging

sounds

interfere

with

each

other,

quarter

tone

scales,

trumpet

"shake"

effects,

and a myriad

of

others.

TREM

(TREMULANT)

This

tab

provides

modulation

of

the

harmonic

content

of

the

tone.

The

harmonic

content,

or

timbre,

is

varied

at a rate

determined

by

the

RATE

control

and

with

an

intensity

determined

by

the

DEPTH

control.

NOTE:

VIB

and

TREM

can

be

used

together.

REP

(REPEAT)

The

repeat

tab

affects

only

those

"QUICK -SET"

voices

which

have

built-in

timbre

changes.

The

timbre

change

associated

with a specific

voice

will

be

repeated

over

and

over

again

at a speed

controlled

by

the

RATE

slide

control.

This

is

easily

demonstrated

by

depressing

MUTE

BRASS,

REP,

OCTAVE 1 and

2,

and

setting

RATE

at

0.

Play a sustained

tone,

then

slowly

move

the

slide

control

to

10

and

return,

while

sustaining

the

tone.

NOTE:

The

DEPTH

slide

control

has

no

effect

on

the

REP

function.

\\s\rui

This

control

provides a most

versatile

tool

in

achieving

the

distinctive

sounds

associated

with

the

MOOG

synthesizer.

It

affects

the

type

of

modu

lation

obtained

by

two

of

the

other

MODULATION

functions,

VIBRATO

and

TREMULANT.

When

this

tab

is in

the

up

position,

VIB

and

TREM

are

with a square-wave

putioui.

The

variation

of

frequency

(VIB),

or

variation

ol

timbres

(TREM),

will

be

very

abrupt

and

choppy.

with

discon

tinuities.

With

VIB,

for

instance, a defmiiivn

variation

in

frequency

can

be

obtained,

like a trill

When

+1/1

rut

is

depressed, a sine

wave

type

of

modulation

is

obtained

which

provides a smooth

variation

of

timbre

or

frequency

-

almost a glissando.

The

difference

between

the

two

effects

is

easily

discernible

in

the

following

ciniructunstically

M00G-

type

settings.

Depress

ii/irut . MUTE

BRASS,

OCTAVE

2,

VIB,

set

RATE

at

3.

and

DEPTH

at

6.

Depress

any

key

on

the

keyboard

and

listen

to

the

smooth

variation

in

frequency

as

you

keep

your

finger

on

the

key.

Then

raise

the

tab

marked

♦b^rut

and

observe

the

abrupt

variation

in

frequency.

Repeat

the

above

steps

with

TREM

instead

of

VIB,

and

then

combine

the

two.

8

Satellite

Slide

Control

Panel

L

EMPHASIS

FILTER

CONTROLS

Once a "Quick-Set"

tab

voice

selection

is

made,

further

refinement

and

adjustment

of

that

voice

may

be

made

by

using

the

three slide

controls

labeled

FILTER.

CONTOUR

This

controls

the

speed

of

the

timbre

change

associated

with

the

onset

of

the

voice,

and/or

the

timbre

change

associated

with

the

release

of

that

voice.

The

wide

range

of

this

control

can

provide

both

slow

settings

(useful

for

simulation

of

bass

violin

or

tuba

effects)

and

fast

timbre

change

settings

(which

can

provide

wild

chirping

effects).

COLOR

This

acts

as a brightness

control,

but

it

has

such

a

wide

range

that

it

can

have

major

effect

on

the

basic

sound

itself.

Your

choice

may

lie

anywhere

between

adding

in a|l

.of

the

high

harmonics

you

wish,

or

eliminating

them.

EMPHASIS

This

control

adds a resonance

frequency

area

to

the

spectrum

of

the

tone.

At

"0",

spectrum

of

the

"Quick-Set"

sound

is

unchanged.

As

the

control

is

pushed

forward,

the

intensity

of

the

sound

within

a

pre-selected

resonance

area

is

increased.

At

maxi

mum,

there

is a well

defined

narrow

sharp

peak

in

the

spectrum

of

the

tone.

FILTER

CONTROLS

SUMMARY

Remember,

the

"Quick-Set"

tabs

establish

an

overall

range

of

sound

and

the

three

Filter

slide

controls

give

you a wide

selection

and

control

within the

limitations

of

that

range.

Try

this:

1.

Depress

OPEN

BRASS

controls

at

"0".

tab,

and

set

the

slide

2.

Play a few

notes

on

the

keyboard.

3.

Play

again

with

various

settings

of

the

COLOR

slide

pot.

The

range

of

sound

will

be

from

that

of

a

very

dull

trumpet

to a very

brassy

one.

4.

Now

do

the

same

with

the

EMPHASIS

control.

The

sound

will

range

through

cornet,

trumpet,

and

flugelhorn

characteristics.

5.

Repeat

with

various

settings

of.

the

CONTOUR

control.

It

will

show

the

wide

range

of

contoured

timbres

in

the

onset

of

the

tones.

ADDITIONAL

CONTROLS

MODULATION

CONTROLS

See

discussion

under

MODULATION

on

page

8.

GLIDE

This

is

one

of

the

most

interesting

of

the

Moog

effects.

Depress

the

GLIDE

tab

and

set

the

GLIDE

slide

control

at

6.

Play

any

note

on

the

keyboard.

Release

this

note

and

quickly

play a second

note

some

distance

away.

The

sound

automatically

glissandos

from

the

first

note

to

the

second.

The

setting

of

the

slide

control

determines

the

speed

of

the

glissando,

(10

is

slow -1

is

fast).

Try a melody

of

detached

notes

and

notice

the

succession

of

glide

attacks.

VOLUME

The

VOLUME

slide

control

provides

finger-tip

adjustment

of

fine

gradations

of

the

Satellite

output.

Major

changes

in

sound

level

are

obtained

by

means

of

the

rotary

knob

on

the

back

of

the

unit.

9

Accessory

and

Connections

For

operation,

the

Synthesizer

unit

should

be

placed

on a horizontal

surface

in a location

which

will

not

interfere

with

its

operation.

NOTE:

Avoid

placement

in

close

proximity

to

electronic

circuitry,

as

on

the

top

of

some

electronic

organs,

because

excessive

hum

may

result.

LO-LEVEL

OUTPUT

130

millivolts

RMS),

Phone

Jack

designed

for

use

with

Guitar

Amplifier,

P.A.

Systems,

etc.

HI-LEVEL

OUTPUT

(1

volt

RMS),

RCA

Phono

Jack

designed

for

use

with

Electronic

Organs.

("Y"

Adapter

and

Accessory

extension

cable

are

included

with

your

unit).

REAR

PANEL

ACCESSORY

EXTENSION

CABLE

ORGAN

AMPLIFIER

RIGHT

OR

MAIN

CHANNEL

INPUT

PLUG

RIGHT

OR

MAIN

CHANNEL

INPUT

JACK

.FROM

ORGAN

Connection

Instructions

SINGLE

CHANNEL

ORGANS

(MONAURAL)

Disconnect

the

RCA

Phono

plug

from

Amplifier

Input

Jack

and

insert

the

"Y"

Adapter

plug

into

the

Amplifier

inpui

Jack.

Connect

Accessory

extension

cable

plug

into

"Y"

Adapter

socket

and

insert

the

plug

on

the

other

end

ol

the

extension

cable

into

the

HI-LEVEL

OUTPUT

jack

on

your

Synthesizer

unit.

Connect

the

organ

plug

(previouslv

removed)

into

the

other

"Y"

Adapter

socket.

DUAL

CHANNEL

ORGANS

(STEREO)

Disconnect

the

RCA

Phono

plug

from

the

Right

of

Main

Channel

Amplifier

Input

Jack

and

insert

"Y"

AOaptoc

plug

into

Right

or

Main

Channel

Input

Jack.

Connect

the

Accessory

extension

cable

plug

into

the

"Y"

Adapter

socket

and

insert

the

plug

on

the

other

end

of

the

extension

cable

into

HI-LEVEL

OUTPUT

jack

on

your

Synthesiser

unit.

Connect

the

Right

or

Main

Channel

plug

(previously

removed)

into

the

other

"Y"

Adapter

socket.

NOTE:

Do

not

connect

the

Synthesizer

into

Leslie

or

Left

Channel

Input.

FILTER

CONTROL

INPUT

This

jack

is

provided

for

the

control

of

the

Timbre

with a Moog

Pedal

controller.

ACCESSORY

SOCKET

,

x

Permits

the

attachment

of a Foot

Pedal

to

control

several

Synthesizer

features.

(Consult

your

dealer

for

availability

of

Moog

Accessories).

10

Care

of

Your

Synthesizers

Your

MOOG

Synthesizer

is

carefully

designed

to

give

you

maximum

pleasure

and

satisfaction

with a minimum

of

care.

Following

these

tips

on

the

care

of

your

Synthesizer

will

help

keep

it

"showroom

new."

■

LOCATION

As

with

any

electronic

instrument,

avoid

placement

in

direct

or

prolonged

sunlight.

Normal

variation

of

temper

ature

will

not

affect

the

tuning

or

electronic

circuitry

of

the

synthesizer.

Storage

location

should

be

chosen

to

avoid

placement

in

front

of

hot

air

registers,

or

beside

an

outside

doorway

in

winter,

as

these

elements

may

affect

the

finish

of

the

cabinet.

•

CABINET

Quality

hardwoods

are

used

in

your

MOOG

Synthesizer.

Therefore,

a

minimum

amount

of

care

wijl

insure

you

of

having

a

piece

of

furniture

that

will

retain

its

beauty.

An

occasional

dusting

with a soft,

dry

cloth

should

remove

both

fingerprints

and

dulling

film.

To

clean

the

keys

a soft

cloth

dampened

in a mild

soap

solution

should

remove

even

the

most

persistent

stains.

Under

no

circumstances

should

solvents

or

cleaning

fluids

be

used

to clean

keys

or

cabinet.

■

POWER

REQUIREMENTS

This

instrument

must

be

operated

from a standard

120

VAC

60Hz

power

outlet.

Normal

line

voltage

variation

will

not

affect

its

operation.

Power

requirements

of

this

unit

are

very

low.

All

solid

state

circuits

are

operated

at

a

very

low

voltage

and

component

life

is

therefore

extended.

■

SAFETY

Your

MOOG

Synthesizer

has

been

designed

for

maximum

safety

in

its

operation

and

trouble

free

performance.

However,

repair

or

service

of

electronic

products

should

be

done

by

qualified

personnel

familiar

with

the

hazards

relating

to

electricity

and

electronic

circuitry.

The

risk

of

repair

or

service

must

not

be

assumed

by

the

customer.

Your

dealer

will

provide

a

competent,

experienced

service

technician

for

that

purpose.

Please

contact

your

dealer,

if

your

unit

needs

repair

or

service.

■

CONCLUSION

And

now

as

you

play

....

Let

us

offer

you

our

best

wishes

for a happy

and

rewarding

experience

with

your

MOOG

Synthesizer.

We

know

it

will

bring

you

great

pleasure

and

creative

satisfaction.

11

TECHNICAL

SERVICE

SECTION

for

MINITMOOG/

SATELLTE

Minitmoog
Model

300A

Satellite

Model

5330

12

CONTENTS

SECTION

PAGE

1

INTRODUCTION

15

2

CIRCUIT

DESCRIPTION

15

2.1

GENERAL

15

2.2

POWER

SUPPLY

15

2.3

KEYBOARD

CIRCUIT

16

2.4

OSCILLATOR

18

2.5

BAND

PASS

FILTER

20

2.6

LOW

PASS

FILTER

20

2.7

VOLTAGE

CONTROLLED

AMPLIFIER

20

2.8

AMPLITUDE

CONTOUR

GENERATOR

21

2.9

FILTER

CONTOUR

GENERATOR

22

2.10

MODULATION

OSCILLATOR

22

2.11

TOUCH

SENSOR

•

22

3

DISASSEMBLY,

VISUAL

INSPECTION

AND

REASSEMBLY

23

3.1

DISASSEMBLY

23

3.2

VISUAL

INSPECTION

23

3.3

PRINTED

CIRCUIT

BOARD

REMOVAL.

23

3.4

REASSEMBLY

,

25

4

TUNING

AND

CALIBRATION

PROCEDURES

25

4.1

GENERAL

25

4.2

OSCILLATOR

TUNING

25

4.3

VOICE

CALIBRATION

29

5

OPERATING

CONTROLS,

INDICATORS

AND

CONNECTORS

31

6

KEYBOARD

MAINTENANCE

AND

ADJUSTMENT

34

6.1

CONTACTS

35

6.2

KEYS

35

6.3

TOUCH

SENSOR

7

TROUBLESHOOTING

GUIDE

37

7.1

POWER

SUPPLY

37

7.2

SOUND

CHAIN

38

7.3

CONTROL

CIRCUITS

40

7.4

OSCILLATOR

TUNING

41

8

MODIFICATIONS

42

8.1

SERVICE

BULLETIN

802

42

8.2

TOUCH

SENSOR

BAR

42

8.3

INSTALLATION

OF

NEW

OR

REBUILT

TOUCH

SENSOR

BAR

45

9

REPLACEMENT

PARTS

LIST

46

10

BLOCK

AND

SCHEMATIC

DIAGRAMS

50

13

LIST

OF

ILLUSTRATIONS

FIGURE

TITLE

PAGE

NO.

2-1

Keyboard

Trigger

Voltage

Waveforms

17

2-2

Emitter

of

Q46

18

2-3

Synchronization

of

Oscillator

B

to

Oscillator

A

19

2-4

Emitter

Voltage

of

Q35

21

2-5

Source

Voltage

of

Q32

21

3-1

Minitmoog

Printed

Circuit

Board

Location

(Inside

View)

24

3-2

Minitmoog

Cover

and

Printed

Circuit

Board

Locations

(Bottom

Views)

....

24

4-1

Minimal

Test

Setup

for

Tuning

25

4-2

Two

Channel

Oscilloscope

Test

Setup

for

Tuning

26

4-3

Main

Board

No. 1 Adjustment

Controls

and

Oscilloscope

Test

Point

Locations

26

4-4

Trigger

at

Collector

of

Q8

27

4-5

Oscillator

B

Trimpot

Locations

(Board

No.

5)

28

4-6

Square

Wave

at

Junction

of

R44

and

R119

29

4-7

Band

Pass

Filter

Q

and

Fc

at

Q41

Source

29

4-8

Filter

Contour

at

Q20

Source

30

4-9

Loudness

Attack

at

Junction

of

R165

and

R166

30

4-10

Loudness

Decay

at

Junction

of

R165

and

R166

30

8-1

Disassembly

of

Minitmoog

42

8-2

Minitmoog

Disassembled

43

8-3

Sensor

Removal

43

8-4

Sensor

Removed

from

Top

Support

44

8-5

Modification

Material

44

8-6

Touch

Sensor

Bar

Reassembled

45

10-1

Minitmoog

Schematic

Diagram

51

10-2

Minitmoog

Block

Diagram

52

10-3

Minitmoog

Printed

Circuit

Board

Assemblies

52

10-4

Minitmoog

Touch

Sensor

Board

Assembly

No. 4 Schematic

Diagram

53

10-5

Minitmoog

Oscillator

Board

Assembly

No. 5 Schematic

Diagram

53

10-6

Satellite

Schematic

Diagram

54

10-7

Satellite

Printed

Circuit

Board

Assemblies

55

10-8

Satellite

Block

Diagram

56

l'i

14

SECTION

1

INTRODUCTION

This

manual

provides

servicing

and

parts infor

mation

for

Minitmoog

Synthesizer

Model

300A

and

Satellite

Synthesizer

Model

5330,

manufactured

by

Moog

Music

Inc.,

2500

Walden

Avenue,

Buffalo,

New

York

14225.

This

manual

was

written

basically

for

the

Minitmoog

Synthesizer

which

includes

the

touch

sensor

board 4 and

oscillator

B

board 5 not

found

in

the

Satellite

Synthesizer.

Differences

in

operating

control

panel

markings

are

indicated

in

Section

5.

Any

major

differences

will

be

noted.

The

Minitmoog

and

Satellite

Synthesizers

are

monophonic

live

performance

synthesizers

intended

primarily

as

auxiliary

instruments

for

keyboardists

and

features

a

dozen

"QUICK-SET"

tabs

that

allow

for

instan

taneous

changes

among

various

voices

preset

with

in

the

instrument.

The

sound

producing

chain

of

the

Synthesizers

consists

of

an

"A"

oscillator

that

produces

both

sawtooth

and

rectangular

waveforms,

a

"B"

scillator

(Minitmoog

only)

that

produces

only

saw

tooth

waveforms,

a

band

pass

filter,

a

low

pass

filter

and a variable

gain

amplifier.

All

five

of

these

circuits

in

the

sound

producing

chain

are

voltage

controlled

and

the

remaining

circuitry

is

devoted

to

producing

appropriate

control

voltages.

The

keyboard

circuit

produces

one

pitch

control

voltage,

the

magnitude

of

which

depends

on

which

key

is

depressed.

In

addition,

the

keyboard

produces

a

trigger

voltage

whenever

one

or

more

of

the

keys

are

depressed.

The

modulating

oscillator

produces

triangular

waveforms

for

modulating

the

oscillators

and

filters.

Two

contour

generators

produce

voltages

that

rise

and

fall

each

time a key

is

depressed.

One

contour

generator

sweeps

one

of

the

filters

while

the

other

sweeps

the

amplifier.

A

resistor

matrix

determines

the

nominal

values

of

the

voltage-controlled

parameters.

The

power

supply

delivers

±

18

volts

unregulated

and

± 9 volts

regulated.

Refer

to

page

52.

The

resistor

matrix

has

fifteen

input

rows

and

twelve

output

columns. A row

is

on

when

+9

volts

is

applied

to

it

and

off

when

it is

open

circuited.

The

two

upper

rows

are

connected

to

the 2 OCT

and 1 OCT

tab

switches,

respectively,

and

shorten

the

contour

times

and

raise

filter

frequencies

when

on.

The

remaining

rows

are

for

the

quick

set

voices

and

only

one

can

be

on

at a time.

The

column

outputs

are

applied

to

low

impedance

points

in

the

circuitry.

Of

the

twelve

matrix

output

columns,

eight

supply

control

currents

for

continuously

variable

parameters,

while

the

remaining

four

supply

switching

current

to

determine

circuit

states.

SECTION

2

CIRCUIT

DESCRIPTION

2.1

GENERAL

The

main

circuit

board

mounts

underneath

the

keyboard

and

contains

a

large

portion

of

the

Synthesizer

circuitry.

All

connections

to

this

board

are

made

through

Molex

connectors.

Looking

at

the

board

from

the

component

side

with

the

connectors

along

the

top

edge,

the

left

connector

is

designated

"A"

and

the

right

connector

is

designated

"B"

with

the

pins

numbered

from 1 to

24

starting

with

the

ief t pin

on

each

connector.

Block

diagrams,

schematic

diagrams

and

printed

circuit

board

diagrams

are

illustrated

in

Section

10

for

quick

reference.

2.2

POWER

SUPPLY

The

unregulated

portion

of

the

power

supply

is

located

on

power

supply

board

No. 2 and

is

completely

conventional.

The

nominal

total

load

supplied

from

each

of

the

unregulated

voltages

is

45

milliamperes.

The

positive

and

negative

voltage

regulator

circuits

for

the

power

supply

are

located

on

main

board

No. 1 .

The

positive

power

supply

voltage

regulator

consists

of

IC1

and

associated

components

and

its

circuitry

is

completely

conventional.

The

supply

delivers

55

or

60

milliamperes

before

voltage

15

developed

across

current

sense

resistor

R2

limits

the

current.

The

negative

power

supply

voltage

regulator

consists

of

IC2,

Ql

and

associated

components

and

adjusts

its

output

to

have

the

same

magnitude

as

the

regulated

+9

volt

output.

No

current

limiting,

other

than

that

supplied

by

R8,

is

provided.

2.3

KEYBOARD

CIRCUIT

The

keyboard

circuit

consists

of

IC3

thru

IC7,

IC9,

IC10

and

related

circuitry.

The

keyboard

contains

a

string

of

thirty-six

100-ohm

resistors

connected

between

pins

A5

and

A6.

The

current

through

the

resistor

string

is

regulated

by

IC7

so

that

the

drop

across

R79

and

R80

is

exactly

4.5

volts.

R79

is

set

so

that

the

voltage

at

pin

A6

is

exactly

-4.5

volts.This

sets a scale

factor

of 3 volts

per

octave

(250

mv

per

semitone).

2.3.1

TRIGGERING

(SINGLE)

The

voltage

at

the

keyboard

buss

is

applied

to

voltage

follower

IC4.

The

keyboard

buss

voltage

rises

to

approximately

7

volts

(detail

A,

Figure

2-1)

when

no

key

is

depressed

because

of

R53.

The

output

of

voltage

follower

IC4

is

applied

to

comparator

IC5

whose

output

swings

from

-16

to

+7

volts

whenever

the

input

goes

below

+4.8

volts

(detail

B).

Q5

and

Q6

comprise

a

monostable

multivibrator

producing

a

pulse

of

approximately

20

milliseconds

duration

(detail

C).

When

the

output

of

IC5

swings

positive,

a

positive

spike

is

applied

through

C7

and

D7

to

the

base

of

Q6,

initiating

a

20

millisecond

pulse.

R63,

R73

and

R72

are

proportioned

so

that

Q7

conducts

only

when

the

output

of

IC5

is

positive

and

the

output

of

the

monostable

multivibrator

(the

collector

of

Q5)

is

negative.

That

is,

Q7

begins

to

conduct

approxi

mately

20

milliseconds

after

a

key

is

depressed

and

stops

conducting

as

soon

as

all

keys

are

released.

When

Q7

conducts,

Q8

is

turned

on

and

the

voltage

at

its

collector

rises

from 0

to

+9

volts.

When

this

happens,

C13

discharges

through

R61

producing

a

ramp

voltage

at

the

base

of

Q4

that

decreases

from

+9

volts

to

-0.6

volt

in

approximately

20

milliseconds

(detail

E).

Emitter

follower

Q4

supplies

a

current

through

R62

and

Q3

to

turn

on

IC10.

IC10

and

Q51

with

associated

circuitry

comprise

a

sample

and

hold

circuit.

When

the

current

ramp

is

applied

to

pin 5 of

IC10,

the

voltage

at

the

source

of

Q51

rapidly

approaches

that

at

the

output

of

IC4.

As

soon

as

the

base

of

Q4

drops

below

0.8

volt,

the

bias

current

being

applied

to

IC10

through

Q3

drops

to

zero

and

the

voltage

at

the

source

of

Q51

remains

constant.

As

long

as

the

output

of

IC5

remains

positive

(that

is,

as

long

as

any

key

is

depressed),

a

very

small

bias

current

of

approximately

50

nanoamperes

flows

through

R59

allowing

IC10

to

supply

a

small

current

to

C5

keeping

its

voltage

constant.

As

soon

as

all

keys

are

released,

the

output

of

IC5

goes

negative

and

IC10

is

virtually

completely

shut

off.

Thus,

when

only

one

key

at a time

is

depressed,

the

voltage

at

the

source

of

Q51

begins

to

approach

the

new

key

voltage

approximately

20

milliseconds

after

the

key

is

depressed

and

this

voltage

is

equal

to

the

new

key

voltage

well

before the

ramp

current

turning

IC10

on

goes

to

zero.

As

long

as a

key

is

depressed,

the

correct

voltage

at

the source

of

Q51

is

maintained

by

the

small

trickle

current

going

through

R59.

When

the

key

is

released,

the

trigger

output

at

the

collector

of

Q8

drops

to

zero,

and

the

sample

and

hold

circuit

no

longer

samples

the

keyboard

voltage.

The

20

millisecond

delay

supplied

by

Q5

and

Q6

is

necessary

to

bypass

the

effect

of

contact

bounce

during

key

depression.

2.3.2

TRIGGERING

{MULTIPLE)

IC6

becomes

important

when

two

keys

are

de

pressed.

Any

abrupt

change

in

voltage

at

the

output

of

IC4

is

applied

through

R66

and

C10

to

the

input

of

IC6.

Cll

filters

out

spikes

less

than

1

millisecond

that

are

associated

with

contact

bounce

or

spurious

interference.

The

resulting

rounded

pulse

is

amplified

by

IC6

(detail

G,

Figure

2-1).

Whenever

the

keyboard

buss

voltage

increases,

the

output

of

IC6

goes

positive,

D9

conducts

and

fires

Q6

producing

a

20

millisecond

positive

going

pulse

at

the

collector

of

Q5.

While

this

20

millisecond

pulse

is

on,

the

trigger

voltage

at

the

collector

of

Q8

drops

to

zero.

Also,

the

collector

of

Q50

drops

to

zero.

This

causes

C13

to

recharge

to

+8.8

volts

at

the

leading

edge

of

the

20

millisecond

pulse

and

resets

the

contour

generators

which

are

described

later.

Thus,

when

a

key

is

held

down

and

a

higher

key

is

depressed,

the

keyboard

sample

and

hold

circuit

again

samples

and

the

trigger

is

reset

momentarily.

The

same

happens

when

a

higher

key

is

released

while

a

lower

key

is

being

held

16

DETAIL

A

IC 4 OUTPUT

KEYBOARD

CONTROL

VOLTAGE

~+7V

+4.5V

OV

-4.5V

I—1ST

KEY

DOWN

t2ND

KEY

DOWN

1ST

KEY-]

JD

KEY

UP—I

up

DETAIL

B

IC 5 OUTPUT

DC

KEYBOARD

DETECTOR

+7V

OV

-16V

DETAIL

C

05

COLLECTOR

TRIGGER

PULSE

+9V

OV

-7V

-12V

■20

MSEC

DETAIL

D

08

COLLECTOR

DC

TRIGGER

+9V

OV

20

MSEC

DETAIL

E

Q4

BASE

KEYBOARD

SAMPLE

AND

HOLD

DRIVE

+8V

DETAIL

F

SOURCE OF

Q51

SAMPLED

KEYBOARD

CONTROL

VOLTAGE

+4.5V

OV

-4.5V

PREVIOUS

NOTE

DETAIL

G

OUTPUT

OF

IC

6

AC

KEY

DOWN

DETECTOR

+8V

+

1.5V

OV

-1.5V

-8V

-I

I*—

1.5

MSEC

1.5V

MIN

(FOR

ADJACENT

SEMITONES)

\r

FIG

URE

2-1

KE

YBOA

RD

TRIGGER

VOL

TA

GE

WA

VEFORMS

17

down

since

Q6

is

fired

by

the

negative

going

output

pulse

of

IC5

coupled

via

C9,

R192,

R78

and

D10.

However,

if

the

higher

key

is

held

and

the

lower

key

is

depressed

or

released,

nothing

will

happen

since

the

keyboard

buss

voltage

remains

constant.

When

all

keys

are

released,

D9

conducts

and a 20

millisecond

pulse

appears

at

the

collector

of

Q5.

However,

the

output

of

IC5

goes

negative,

so

that

when

the

collector

of

Q5

again

goes

negative,

Q8

is

not

reset.

2.3.3

KEYBOARD

CONTROL VOLTAGE

IC3

is a voltage

follower

whose

output

is

the

voltage

of

the

last

key

depressed.

Variable

resistor

R12

controls

the

glide

rate

and

is

connected

between

pins

A7

and

A24.

The

time

constant

of

this

resistor

and

C4

determines

the

glide

rate.

IC9

and

Q2

comprise

another

voltage

follower.

The

difference

between

this

voltage

follower

and

IC3

is

the

amount

of

input

current

required.

IC9

is

biased

at a low

current

level

so

that

input

current

does

not

result

in

a

pitch

error

when

the

glide

rate

potentiometer

is

at

its

maximum

resistance.

The

voltage

at

the

emitter

of

Q2

determines

the

pitch

of the

audio

oscillators

and

is

also

applied

to

the

filters

and

contour

generators

so

that

as

the

keyboard

voltage

goes

up, the

filter

frequency

also

goes

up

and

the

contour

time

constants

decrease.

2.4

OSCILLATOR

IC8

is a dc

summer

adding

pitch,

one-octave

transpose

voltage,

a

tuning

voltage

from

the

fine

tuning

potentiometer

on

the

rear

panel,

a

modulating

voltage

and

the

voltage

from

the

touch

sensor.

R14

is a temperature

compensating

feedback

resistor.

The

summation

constant

increases

with

a

temperature

coefficient

of

approximately

3400

parts

per

million.

The

relationship

between

R14

and

the

input

resistors

is

such

that

the

output

of

IC8

decreases

approximately

20

millivolts

for

each

octave

increase

in

frequency.

2.4.1

OSCILLATOR

A

The

oscillator

A

audio

sawtooth

waveform

is

generated

by

linearly

discharging

C38

through

one

of

the

transistors

in

IC11,

then

rapidly

recharging

it

through

Q45.

The

current

discharging

C38

is

determined

by

the

voltage

difference

between

pins

2

and 4 of

IC11.

The

ratio

of

currents

through

these

two

transistors

in

IC11

is

an

exponential

function

of

the

voltage

difference

between

their

bases.

The

current

fed

into

pin 1 of

IC11

is

kept

constant

by

IC21

which

maintains

the

voltage

at

pin 1 at

the reference

voltage

appearing

at

the

junction

of

R28

and

R29.

It

ac

complishes

this

via

current

feedback

to

pin 3 of

IC11.

The

overall

effect

is

that

C38

discharge

current

doubles

(increases

1

octave)

for

each

20

mv

increase

across

pins 2 and 4 of

IC11.

When 2 OCT

switch

is

up,

R30

conducts

and

Q49

is

saturated,

effectively

placing

the

series

combination

of

R20

and

R21

in

parallel

with

R19.

The

current

at

pin 1 of

IC11

is

then

de

termined

by

the current

flowing

through

parallel

resistors

R19

and

R20/R21.

When 2 OCT

switch

is

down,

R30

does

not

conduct,

Q49

is

open,

and

R20/

R21

are

out

of

the

circuit.

Thus

the

current

flowing

into

pin 1 of

IC11

is

25

percent

as

much

when

Q49

is

open

as

it

is

when

it

is

saturated

and,

for

the

same

voltage

difference

between

the

bases,

the

current

flowing

into

pin 5 is

also

25

percent

as

much.

The

lower

end

of

C38

is

applied

to

low-input-

bias-current

voltage

follower

IC12/Q46.

The

voltage

at

the

emitter

of

Q46

is

applied

to

Schmitt

trigger

Q43

and

Q44.

The

Schmitt

trigger

has a high

hysteresis

factor

and

when

the

voltage

descends

to

the

point

where

the

Schmitt

trigger

fires,

Q45

is

turned

on

and

C38

is

rapidly

recharged.

The

Schmitt

trigger

begins

to

shut

off

when

the

recharge

is

approximately

66

percent

complete.

Because

of

the

storage

time

of

Q44

and

Q45,

C38

is

fully

recharged

before

Q45

is

completely

off.

2.4.2

OSCILLATOR A WAVESHAPING

The

sawtooth

wave

developed

at

the

emitter

of

Q46

(Figure

2-2)

is

applied

through

R41

to

the

base

of

Q47

and

through

R43

to

the

collector

of

Q48.

The

width

of

the

rectangular

wave

that

appears

at

the

collector

of high

gain

amplifier

Q47

depends

on

the

bias

current

supplied

through

R45

from

the

output

FIGURE

2-2

EMITTER

OF

Q46

18

of

IC13.

The

control

current applied

to

the

input

of

IC13

from

the

resistor

matrix

determines

the

out

put

voltage

of

IC13.

When

the

control

current

is

zero,

Q47

remains

saturated

throughout

the

entire

sawtooth

cycle.

Q48

is

also

biased

by

IC13

(via

R118)

and

remains

shut

off

and

as a result,

the

output

voltage

is

the

undistorted

sawtooth.

As

the

control

current

increases,

the

voltage

at

the

output

of

IC13

goes

negative.

When

it is

approximately

-1

volt,

the

current

through

R118

is

sufficient

to

completely

saturate

Q48

and

effectively

short

out

the

sawtooth

waves.

When

it

is

approximately

-3

volts,

Q47

begins

to

conduct

on

part

of

the

sawtooth

cycle

and a narrow

rectangular

waveform

appears

at

its

collector.

When

the

voltage

at

the

output

of

IC13

is

approximately

-9

volts,

the

clipping

of

Q47

is

symmetrical

and a square

wave

appears

at

its

collector.

Thus,

the

waveform

at

the

junction

of

R119

and

R44

is

first

a

sawtooth

when

the

control

current

into

IC13

is

zero,

then

changes

to a narrow

rectangular,

then

to a broad

rectangular,

and

finally

to a square

wave

as

the

control

current

is

increased.

This

waveform

is

applied

to

the

band

pass

filter

via

an

attenuator

network

associated

with

oscillator

board

No. 5 (oscillator

B).

2.4.3

OSCILLATOR B (Minitmoog

Only)

The

circuitry

for

the

second

oscillator

is

located

on

oscillator

board

No. 5 and

consists

of a

current

source

network,

sawtooth

oscillator

and a mixing

network

for

combining

the A and B oscillator

tones.

The

sawtooth

waveform

is

produced

by

charging

C503

through

line P and

discharging

it

by

turning

on

Q501.

The

current

through

line P is

supplied

from

one

of

the

transistors

in

IC11

on

the

main

board.

This

particular

transistor

is

located

on

the

same

chip

with

the

current

source

transistor

for

oscillator

A

and

its

characteristics

are

very

close

to

those

of

the

oscillator

A

current

source.

As a result,

the

ratio

of

oscillator

A

to

oscillator

B

currents

will

be

fairly

constant

as

the

instrument's

pitch

is

varied.

Resistors

R501

thru

R510

supply a relatively

small

voltage

change

at

pin M to

vary

the

ratio

between

oscillator

currents

by a factor

of

4.

Oscillator

B

range

trimpot

R504

sets

the

center

value

of

oscillator

B

pitch.

When

pin T is

grounded

by

the

f

SYNC

tab

switch,

the

"B"

PITCH

control

moves

oscillator

B

pitch

up

and

down

an

octave

relative

to

oscillator

A.

When

pin V is

grounded

by

the

SYNC

tab

switch,

the

aB"

PITCH

control

sweeps

the

natural

frequency

of

oscillator

B

over a range

of

more

than

four

octaves.

In

this

case,

R505

shifts

the

pitch

of

oscillator

B

such

that

oscillators

A

and B are

approximately

in

unison

when

the

"B"

PITCH

control

is

fully

counterclockwise.

Note

that

the

"B"

PITCH

control

is

centertapped

with a center

deadband

to

allow

the

musician

to

quickly

and

precisely

set

oscillator

B

pitch

in

unison

with

oscillator

A.

Octave

trimpot

R510

is

set

so

that

the

pitch

of

oscillator

B

is

either

an

octave

above

or

below

that

of

oscillator

A

when

the

"B"

PITCH

control

is

at

either

end

of

its

rotation.

The

oscillator

circuitry

consists

of

IC501,

IC502

and

Q501

with

related

circuitry.

Q502

and

Q503

are

active

only

when

oscillator

B

is

synchron

ized

to

oscillator

A. A positive

going

pulse

is

produced

at

the

output

of

Schmitt

trigger

IC502

when

the

output

voltage

of

integrator

IC501

surpasses

the

threshold

voltage

at

the

junction

of

R514

and

R531.

Q501

is

turned

on

for

approximately

10

microseconds.

Trimpot

R511

increases

the

frequency

at

high charging

currents

and

is

used

as

a

high

end

tuning

adjustment.

The

sawtooth

waveform

appears

at

the

output

of

IC501.

Sync

pulses

from

oscillator

A

are

applied

at

pin

R

to

the

base

of

Q502.

When

+9

volts

are

connected

to

pin Q by

the

SYNC

tab

switch,

Q502

is

always

saturated.

When

pin Q is

grounded

by

the

SYNC

tab

switch,

the

sync

pulses

turn

Q502

off

and

Q503

on

once

for

every

cycle

of

oscillator

A.

When

Q503

conducts,

the

threshold

of

IC502

drops

to

0 and

the

oscillator

B

waveform

starts

over

(Figure

2-3).

Resistors

R522

thru

R525

form

the

mixing

network.

The

A/B

MIX

control

on

the

front

panel

FIGURE

2-3

SYNCH

RON

IZA

TION

OF

OSCIL

LA

TOR

B

TO

OSCILLATOR

A

19

shunts

varying

proportions

of

oscillators

A

and B to

ground.

The

values

of

resistors

R522

thru

R525

relative

to

the

value

of

the

A/B

MIX

control

are

set

so

that

the

signal

power

sum

at

pins Z and

ZZ

tends

to

remain

constant

as

the

A/B

MIX

control

is

rotated.

The

output

at

pin Z is

the

oscillator

A

signal

applied

to

the

normal

input

portion

of

the

band

pass

filter

via

R122

and

R124.

The

output

at

pin

ZZ

is

the

oscillator

B

signal

applied

further

down

the

chain

of

the

band

pass

filter

to

produce

a

different

sound

character.

2.5

BAND

PASS

FILTER

The

band

pass

filter

consists

of

IC15,

IC16

and

IC17

with

associated

components.

IC16

and

IC17

are

identical

integrators

effectively

connected

in

series

and

their

gains

determine

the

center

frequency

of

the

band

pass

filter

while

the

gain

of

IC15

determines

the

bandwidth

(Q).

These

gains

are

set

by

bias

currents

applied

from

transistor

pairs

Q39/Q40

and

Q37/Q38,

respectively.

These

transistor

pairs

may

be

compared

directly

to

the

transistor

pair

in

ICll

which

determines

the

frequency

of

oscillation.

The

main

difference

is

that

relatively

constant

currents

are

fed

to

these

transistor

pairs

through

R133

and

R129. A precise,

wide

range

relationship

between

output

current

and

base-to-base

voltage

is

not

required

of

these

transistor

pairs.

Only

reasonable

repeatability

and

the

rough

approximation

of

exponential

characteristics

are

required.

2.5.1

BAND

PASS

FILTER

CONTROL

INPUTS

The

bandwidth

is

determined

by

the

voltage

difference

between

the

bases

of

Q37

and

Q38.

The

voltage

at

the

base of

Q37

is

the

result

of

the

band

width

control current

flowing

through

R128.

An

increase

of

18.5

mv

doubles

the

bandwidth.

The

one

source of

bandwidth

control current

is

column

8

of

the

resistor

matrix.

The

center

frequency

is

deter

mined

by

the

voltage

difference

between

the

bases

of

Q39

and

Q40.

The

voltage

at

the

base

of

Q40

is

the

result

of the center

frequency

control

currents

flowing

through

R134.

An

increase

of

18.5

mv

doubles

the

center

frequency.

The

currents

come

from

column

7

of

the

resistor

matrix,

the

BRIGHTNESS

potentiometer

voltage

applied

to

R193,

the

FILTER

CONTROL

INPUT

jack

voltage

applied

to

R184,the

modulation

voltage

applied

to

R181,

the

filter

contour

voltage

applied

to

R116

and

the

keyboard

pitch

voltage

applied

through

R179

and

R180.

The

current

from

column 4 of

the

resistor

matrix

deter

mines

whether

or

not

Q25

conducts.

When

Q25

conducts,

it

becomes

saturated

and

shorts

out

the

keyboard

voltage

controlling

the

center

frequency.

R130

and

R132

are

offset

adjustments

for

setting

correct

values

of

bandwidth and

center

frequency,

respectively

and

compensate

for

transistor

offset

voltages,

resistor

variations

and

gain

variations

of

IC15,

IC16

and

IC17.

2.6

LOW

PASS

FILTER

The

output

of

the

band

pass

filter

is

taken

from

the

source

of

Q41

and

applied

across

the

bases

of

the

bottom

transistor

pair

of

IC19.

This

transistor

pair

and

the

two

immediately

following

it

constitute

a

low

pass

filter

whose

cutoff

frequency

is

proportional

to

the

standing

current.

This

current

is

determined

by

the

voltage

difference

between

pin

13

(ground)

of

IC19

and

the

base

of

Q33.

The

voltage

at

the

base

of

Q33

is

the

result

of

cutoff

frequency

currents

flowing

through

R151.

These

currents

come

from

column

9

of

the

resistor

matrix,

the

BRIGHTNESS

potentiom

eter

voltage

applied

to

R186,

FILTER

CONTROL

INPUT

jack

voltage

applied

to

R185,

modulation

voltage

applied

to

R187

and

filter

contour

voltage

applied

through

R117.

The

setting

of

R139

deter

mines

the

calibration

current

through

R140.

An

increase

of

approximately

18.5

mv

at

the

base

of

Q33

results

in a one

octave

increase

in

the cutoff

frequency

of

the

low

pass

filter.

2.7

VOLTAGE

CONTROLLED

AMPLIFIER

The

transistor

pair

with

common

emitters

on

pin

3

of

IC20

controls

the

amplitude

of

the

audio

wave

form by

variable

transconductance.

The

current

which

determines

this

transconductance

is

determined

by

the

voltage

at

pin

12

of

IC20

and

the

resistance

between

pin

13

and

ground.

The

voltage

applied

to

pin

12

is

the

amplitude

contour

voltage

and

the

resistance

from

pin

B19

to

ground

is

the

100K

VOLUME

control

potentiometer.

IC22

is a differential

amplifier,

the

output

of

which

is

the

final

audio

waveform.

20

2.8

AMPLITUDE

CONTOUR

GENERATOR

Of

the

two

contour

generators,

the

amplitude

contour

generator

is

the

simplest,

so

it

will

be

described

first.

This

contour

generator

consists

of

Q34,

Q35,

Q36,

IC18,

transistor pairs

Q26/Q27

and

Q28/Q29,

Q30,

Q31,

Q32

and

associated

circuitry.

When

the

leading

edge

of

the

trigger

occurs,

Q35

partially

charges

C25

so

that

the

emitter

of

Q35

rises

to

approximately

3.5

volts.

If

Q36

is

saturated,

Q34

does

not

conduct

at

all.

Column 3 of the

resistor

matrix

determines

whether

or

not

Q36

is

turned

on.

If

Q34

is

not

turned

on,

C25

is

free

to

immediately

begin

linearly

discharging

through

Q26.

The

dis

charging

current

from

Q26

is

determined

by

the

voltage

control

developed

across

R189.

If

Q36

is

off,

Q34

holds

the

voltage

at

+3.5

volts

until

the

end

of

the

dc

trigger

occurs

(detail

D,

Figure

2-1).

Thus,

the

voltage

at

the

emitter

of

Q35

is

as

shown

in

Figure

2-4.

The

rise

time

of the

voltage

at

the

emitter

of

Q35

is

determined

only

by

the

ability

of

Q35

to

discharge

C25.

Typically,

this

rise

time

is

less

than 1 millisecond.

The

decay

time

of

the

amplitude

contour

is

determined

by

the

voltage

difference

between

the

bases

of

Q26

and

Q27.

The

voltage

across

R189

results

from

the

amplitude

contour

decay

time

control

currents

coming

from

column 2 of

the

resistor

matrix,

the

keyboard

voltage

applied

to

R199

and

the

shaping

current

from

R169

and

R171.

R190

corrects

for

transistor

offsets

and

other

normal

component

variations.

A

voltage

increase

of

18.5

mv

at

the

base

of

Q26

cuts

the

decay

time

in

half.

IC18,

C35

and

Q32

comprise

a

voltage

follower

whose

slew

rate

is

proportional

to

the

bias

cur

rent

of

IC18.

This

bias

current

applied

from

the

collector

of

Q28

is

determined

by

the

voltage

difference

between

the

bases of

Q28

and

Q29.

Thus,

since

the

decay

time

of

an

envelope

is

generally

longer

than

the

attack

time,

the

voltage

appearing

at

the

source

of

Q32

has

an

attack

time

inversely

proportional

to

the

collector

current

of

Q26.

The

contributions to

attack

time

control

are

similar

to

those

of

decay

time

control.

The

quick-set

current

comes

from

column 1 of

the

resistor

matrix.

Since

Q26

is a nearly

ideal

current

source,

the

decay

slope

at

the

source

of

Q32

would

be a straight

line

if

not

for

the

action

of

Q30.

At

the

beginning

of

the

decay

slope,

the

voltage

at

the

base

of

Q30

is

more

positive

than

the

emitter,

and

Q30

does

not

conduct.

When

the

base

of

Q30

approaches

-0.6

volt

(i.e.,

when

source

of

Q32

is

equal

to

+1.8

volts),

Q30

acts

as

an

emitter

follower

and

the

cur

rent

through

R169

flows

to

R189

and

slows

down

the

decay

slope.

The

more

negative

the

base

of

Q30

goes,

the

higher

its

control

current

and

the

more

the

decay

slope

decreases.

This

gives

the

decay

slope

an

extended

tail

and

therefore

sounds

like a more

natural

exponential

decay.

(See

Figure

2-5.)

When

the

voltage

at

pin

B21

is

+9

volts,

Q31

is

saturated

and

very

little

current

flows

through

R171.

When

the

voltage

at

pin

B21

is

zero,

Q31

is

open

and

current

flows

through

R170

and

R171

to

greatly

speed

up

the

decay

slope.

The

SUST

tab

switch

connects

pin

B21

to

+9

volts

when

it

is

down

and

to

the

trigger

line

when

it

is

up.

As a result,

the

tone

is

rapidly

squelched

when

the

SUST

tab

switch

is

up

and

the

keys

are

released.

As

noted

previously,

the

keyboard

pitch

voltage

controls

both

attack

and

decay

times

through

R199

and

R198,

respectively.

These

times

change

by a factor

of

approximately

2.5

over

the

complete

keyboard

range.

KEY

DOWN

035

EMITTER

(Q36OFF)

OV

-0.6

V

+3.5V—

Q35

EMITTER

(Q36

ON)

0V

-0.6V

=f

r

KEY

UP

FIGURE

2-4

EMITTER

VOL

TAGE

OF

Q35

+3.5V

Q32

SOURCE

(Q36OFF)

0V

-0.6V

+3.5V-

032

SOURCE

(Q36

ON)

OV

-0.6

V

h-KEYDOWNh—

KEY

UP

FIGURE

25

SOURCE

VOL

TAGE

OF

Q32

21

2.9

FILTER

CONTOUR

GENERATOR

The

filter

contour

generator

contains

most

of the

features

of

the

amplitude

contour

generator.

Q15

of

the

filter

contour

generator

corresponds

to

Q35

of

the

amplitude

contour

generator,

Q13

to

Q34

and

Q12

to

Q36.

The

filter

decay

mode

control

voltage

from

matrix

column

11

through

R88

and

R91

determines

whether

the

filter

contour

will

rise

and

then

immediately

fall

or

fall

only

upon

release

of

all

keys.

Q9

and

Q10

of

the

filter

contour

generator

corresponds

to

Q26

and

Q27

of

the

amplitude

contour

generator.

The

current

from

Q10

determines

the

decay

time

of

the

contour.

Similarly,

IC14

corresponds

to

IC18,

Q18/Q19

corresponds

to

Q28/Q29

and

Q16

corresponds

to

Q30.

R95

and

R101

couple

the

key

board

voltage

to

the

attack

and decay

control

circuits.

The

voltage

applied

to

pin

B18

from

the

ATTACK

potentiometer

varies

the

attack

time

of

the

filter

contour.

The

voltage

applied

to

pin

813

from

the

DECAY

potentiometer

varies

the

decay

time

of

the

filter

contour.

Q22

and

Q23

are

routing

switches

and

only

one

is

on

at a time.

The

filter

contour

routing

control

voltage

from

matrix

column 5 determines

whether

Q17

is

open

or

saturated.

If

Q17

is

open,

then

Q21

is

also

open

and

Q24

is

saturated.

Thus,

Q22

is

biased

on

and

Q23

is

biased

off

and

the

contour

is

routed

to

the

low

pass

filter.

On

the

other

hand

if

Q17

is

saturated,

Q23

is

biased

on

and

the

contour

is

routed

to

the

center

frequency

control

input of the

band

pass

filter.

2.10

MODULATION

OSCILLATOR

The

modulation

oscillator

is

mounted

on

power

supply

board

No. 2 along

with

seven

slide

potentiom

eters

and

consists

of

Schmitt

trigger

IC1 and

integrator

IC2

with

their

associated

components.

The

output

of

IC2

is a triangular

waveform

and

the

output

of

IC1

is

a

square

wave.

The

current

supplying

integrator

IC2,

and

therefore

the

oscillator

frequency,

is

varied

over

the

frequency

range

of 1 to

50

Hz

by

RATE

control

RIO.

2.11

TOUCH

SENSOR

2.11.1

MECHANISM

The

touch

sensor

mechanism,

mounted

under

neath

the keys,

has a 20

inch

long

anodized

aluminum

rod

on

which a key

bears

when

it

is

fully

down

(bottomed).

Excess

key

pressure

forces

the

rod

to

compress

its

foam

rubber

support

pad

causing

the

rod

to

come

into

more

intimate

contact

with

the

grounded

conductive

nylon

strip

glued

to

the

foam

rubber

pad.

The

assembly

functions

as a variable

capacitor

and

the

more

force

with

which

one

holds

a

key

down,

the

greater

the

capacitance.

The

touch

sensor

circuit

on

board

No. 4 senses

this

capacitance

increase

and

produces

a

dc

control

voltage

ranging

from 0 (no

excess

pressure)

to

.+6

volts

(maximum

pressure).

2.11.2

VARIABLE

FILTER

AND

AVERAGE

VALUE

DETECTOR

Multivibrator

IC401,

located

on

touch

sensor

board

No.

4,

produces

a

square

wave

at a nominal

frequency

of

100

KHz.

The

touch

sensor

element

is a variable

capacitance

(C410)

connected

across

pin E and

ground.

C410

and

R402

form a variable

low

pass

filter

wherein

the

peak-to-peak

voltage

at

pin E decreases

as

the

value

of

variable

capacitor

C410

increases.

C402

couples

the

waveform

to

clamp

CR401.

The

dc

component

of

the

signal

appearing

at

CR401

becomes

less

negative

as

the

touch

sensor's

capacitance

is

increased.

R403

and

C403

filter

out

the

ac

components

leaving

only

the

dc

component

of

the

signal

to

be

applied

to

emitter

follower

Q401.

R404

at

the

emitter

of

.Q401

and

C404

provide

additional

filtering

of

the

output

signal.

2.11.3

DC

RESTORER

The

keyboard

circuitry

generates a

trigger

voltage

which

is

applied

to

pin A of

board

No.

4

whenever

a

key

is

depressed.

With

no key

depressed,

this

voltage

is

zero,

Q403

conducts

and

IC402

turns

on.

The

voltage

at

the

junction

of

R404

and

R406

(pin 2 of

IC402)

is

kept

very

close

to

zero

when

the

input

trigger

is

zero

through

a

feedback

loop

consisting

of

Q402

and

R406.

Whenever

any

key

is

depressed,

the

trigger

voltage

at

pin A rises

to

+9

volts

and

Q403

shuts

off,

shutting

off

IC402.

C405

holds

the

voltage

that

existed

before

the

trigger

appeared

and

the

junction

of

R406

and

R404

remains

close

to

zero

until

the

touch

sensor

element

capacitance

increases.

When

the

element's

capacitance

begins

to

increase

22

(as a result

of

pressing

down

harder

upon a key),

the

voltage

at

the

junction

of

R404

and

R406

begins

to

-i$e.

Thus

IC402,

Q402,

Q403

and

related

circuitry

yrnPa

dc

restorer

that

keeps

the

voltage

at

the

junction

of

R404

and

R406

at

zero

until

a

key

is

depressed

and

returns

it

to

zero

when a key

is

released.

2.11.4

AMPLIFIER

The

voltage

at

the

junction

of

R404

and

R406

is

applied

to

open

loop

amplifier

IC403.

The

value

of

R408

is

set

so

that

the

input

of

IC403

begins

to

saturate

when

the

touch

control

output

rises

to

ap

proximately

50

percent

of

its

maximum

value

and

saturates

more

and

more

as

the

touch

sensor

element

is

depressed

further*

This

allows

the

touch

sensor

to

be

more

sensitive

at

the

beginning

of

its

travel

and

to

become

increasingly

less

sensitive

as a key

is

depressed

with

more

force.

The

touch

control

output

at

pin G rises

from

0

to

approximately

+6

volts

and

sweeps

the

filters,

both

oscillators

or

just

the

second,

oscillator

depending

on

how

the

front

panel

touch

sensor

switches

are

set.

2.11.5

MODULATION

AMOUNT

The

touch

control

output

from

pin 6 of

IC403

is

also

applied

through

R411

and

Q404

to

control the

gain

of

IC404.

The

triangular

modulation

wave

is

applied

at

pin H from

the

output

of IC2.

The

modu

lating signal

of

varying

amplitude

at

pin J is

available

for

modulation

when

the

TOUCH

CONTROLS

MOD

tab

switch

is

depressed.

It

should

be

noted

that

the

ratio

between

R412

and

R413

is

set

so

that

C409

rounds

off

the

triangular

wave

to

yield a

desirable

sinusodial

wave

effect.

SECTION

3

DISASSEMBLY,

VISUAL

INSPECTION

AND

REASSEMBLY

3.1

DISASSEMBLY

3.2

VISUAL

INSPECTION

Disassembly

and

inspection

are

essentially

the

same

for

both

Synthesizers

except

where

the

Touch

Sensor

Board 4 and

the

Oscillator

Board 5 are

mentioned.

These

boards

are

used

only

on

the

Minitmoog.

a)

Disconnect

power

cord

connector

and

all

other

rear

panel

connections.

b)

Stand

instrument

on

one

ei.d

and

remove

three

screws

securing

large

bottom

cover

(Figure

3-1)

to

instrument

using a medium

sized

Phillips

head

screwdriver

and

remove

cover.

NOTE

All

internal

alignment

and

adjustment

controls

are

now

accessible.

c)

If

necessary,

the

narrow

bottom

cover

may

be

removed

by

taking

out

an

additional

10

screws.

a)

Inspect

instrument

for

broken

wires,

loose

printed

circuit

boards

or

electrical

connectors,

cable

harness

wires

pushed

into

keyswitches

and

rotary

pots

with

terminals

shorted

to

chassis.

b)

Check

for

frayed

conductive

nylon

on

touch

sensor

assembly

shorting

to

keyboard

switch

assembly.

3.3

PRINTED

CIRCUIT

BOARD

REMOVAL

a)

Main

Board

No. 1 -

Disconnect

5

electrical

connectors,

depress

levers

on 6 fastening

devices

and

remove

board

from

bottom

cover.

(See

Figure

3-1.)

b)

Power

Supply

Board

No. 2 -

Remove 7 slide

knobs,

narrow

bottom

cover, 2 electrical

connectors,

2

screws

and 1 foot

and

carefully

lift

power

supply

from

instrument.

WARNING

Removing

narrow

bottom

cover

exposes

live

terminals

of

the

ac

POWER

tab

switch.

Use

extreme

care

when

power

cord

is

connected

to

primary

power.

WARNING

Removing

narrow

bottom

cover

exposes

live

terminals

of

the

ac

POWER

tab

switch.

Use

extreme

care

when

power

cord

is

connected

to

primary

power.

23

POWER

SUPPLY

BOARD

NO.

2

"B"

OSCILLATOR

BOARD

NO.

5

MATRIX

BOARD

NO.

3

.

(NOT

VISIBLE)

TOUCH

SENS.OR

BOARD

NO.

4

MAIN

BOARD

NO.

1

FIGURE

3-1

MINITMOOG

PRINTED

CIRCUIT

BOARD

LOCATIONS

(INSIDE

VIEW)

RESISTOR

MATRIX

BOARD

NO.

3

CONNECTORS

D

B

CONNECTORS

D

CONNECTOR

OSCILLATOR

BOARD

NO. 5 (MINITMOOG

ONLY)

MAIN

BOARD

NO.

1

POWER

SUPPLY

BOARD

NO.

2

e

0

e

©Do

©

CONNECTORS

TOUCH

SENSOR

BOARD

NO. 4 (MINITMOOG

ONLY)

\

\

C.'.T

rz-v

x-

KEYBOARD

FIGURE

3-2

MINITMOOG

COVER

AND

PRINTED

CIRCUIT

BOARD

LOCATIONS

(BOTTOM

VIEWS)

24

c)

Resistor

Matrix

Board

No. 3 —

Disconnect

electrical

connector,

depress

levers

on 4 fastening

devices

and

remove

board

with

cable

assembly

attached.

Jisconnect

"D"

connector

on

main

board

No.

1.

d)

Touch

Sensor

Board

No. 4 — Disconnect

electrical

connector,

remove 2 nuts

and

carefully

lift

board

from

instrument.

e)

Oscillator

Board

No. 5 —

Disconnect

2

electrical

connectors,

remove 2 nuts

and

carefully

lift

board

from

main

board

No.

1.

f)

Keyboard — Remove

cabinet

by

taking

out

4

small

screws

on

the

end

pieces.

Remove

narrow

bottom

cover.

Disconnect

1

snap

fastener

and

unsolder

3

wires

(1

at

top

and 2 at

bottom).

Remove

2

large

screws

and

washers,

2

hex

head

screws

securing

L-bracket

to

rear

of

keyboard

frame

and

carefully

lift

keyboard

from

chassis.

3.4

REASSEMBLY

a)

Keyboard

-

Reassemble

keyboard

in

the

reverse

order

of

disassembly

making

certain

that

the

2

large

washers

between

the

chassis

and

keyboard

frame

are

not

forgotten

and

that

the 2 screws

do

not

touch

the sensor

assembly.

b)

Oscillator

Board

No. 5 -

Make

certain

insulating

spacers

are

reinstalled

so

that

nuts

do

not

short

out

top

or

bottom

side

of

board.

c)

Large

Bottom

Cover -Ascertain

harness

wires

are

not

forced

into

keyswitches.

Assure

cover

does

not

pinch

matrix

harness

wires

passing

through

cutout

in

chassis.

SECTION

4

TUNING

AND

CALIBRATION

PROCEDURES

4.1

GENERAL

Tuning

and

calibration

procedures

are

essentially

the

same

for

both

Synthesizers.

Unless otherwise

indicated

the

following

instructions

apply

to

both

units.

The

oscillator

tuning

procedure,

paragraph

4.2,

provides

a

method

of tuning

the

instrument

for

proper

oscillator

range,

scale,

octave

shift

and

tracking.

A

voice

calibration

procedure,

paragraph

4.3,

provides

a

method

of

calibrating

the

sound

modifying

circuits

to

voice

the

presets.

4.2

OSCILLATOR

TUNING

4.2.1

TEST

SETUP

A

stable

oscillator

(or

another

synthesizer)

is

required

to

provide

a

reference

tone

(hereafter

referred

to

as

REF)

tunable

a

few

semitones

above

and

below

Bb4

(466

Hz).

REFERENCE=

=

466Hz

In

addition,

an

oscilloscope,

digital

voltmeter

(DVM)

and

an

amplifier/speaker

system

is

required

for

tuning

and

calibration

and

oscillator

board

No.

5

must

be

carefully

raised

(not

disconnected)

from

main

board

No. 1 to

gain

access

to

trimpots

R16

and

R190.

The

minimal

test

setup

shown

in

Figure

4-1

will

suffice.

However

the

setup

shown

in

Figure

4-2

will

prove

to

be

much

more

convenient

and

FIGURE 4 1

MINIMAL

TEST

SETUP

FOR

TUNING

25

FIGURE

4-2

TWO

CHANNEL

OSCILLOSCOPE

TEST

SETUP

FOR

TUNING

should

be

used

if a two

channel

oscilloscope

is

available.

In

the

test

setup

of

Figure

4-2,

display

height

and

audio

level

are

independent

and

it

is

not

necessary

to

trigger

the

oscilloscope

off

of a composite

waveform.

Trigger

the

oscilloscope

off

the

lower

of

the

two

frequencies.

4.2.2

POWER

SUPPLY

ADJUSTMENT

(Minitmoog

Only)

a)

Connect

DVM

across

pins J (+)

and K (-)

of

oscillator

board

No. 5 and

turn

+9

volt

adjust

trimpot

R4

on

main

board

No. 1 (Figure

4-3)

until

the

+9

volt

line

is

exactly

+9.000 V ±10

mv.

b)

Connect

DVM

across

pins L (-)

and K (+)

of

oscillator

board

No. 5 and

verify

that

the

-9

volt

line

is

-9.000 V ±200

mv.

4.2.3

KEYBOARD

CURRENT

ADJUSTMENT

a)

Connect

DVM

across

pins

A5

(+)

and

A6

(-)

OCT1

OSCILLATOR

AMPLITUDE

KEYBOARD

ADJ

A

HIGH

SCALE

RANGE DECAY

ADJ

RIO

FREQUENCY

R17

R16

R190

R79

+9V

ADJ

\VIBRATO

ADJUST

/

R14

UNDER

IC11

0

VCA

BAL

R160

JUNCTION

R165ANDR166

AMPLITUDE

R162 \ ATTACK

IC22

\

\

R174

08

/

R47

JUNCTION

R130

R21

\

Q41

R132

R64

SQUARE

OF

R44

BAND

OCT2

\

CENTER

WAVE

ADJ

ANDR119

WIDTH

ADJ

JUNCTION

FREQ

ADJUST

R149

AND

C30

ADJ

\

Q20

R98

R139

R105

FILTER

LOW

PASS

FILTER

DECAY

CUTOFF

ATTACK

FIGURE

4-3

MAIN

BOARD

NO. 1 ADJUSTMENT

CONTROLS

AND

OSCILLOSCOPE

TEST

POINT

LOCA

TIONS

26

of

main

board

No. 1 and

observe

voltage

drop

across

keyboard.

b)

Adjust

keyboard

trimpot

R79

(Figure

4-3)

for

a

voltage

indication

of

+9.000 V +10

mv.

4.2.4

TRIGGERING

a)

Connect

oscilloscope

to

the

collector

of

Q8

(Figure 4-3)

and

verify

that

the

trigger

voltage

wave

form

present

is

as

shown

in

Figure

4-4

with a single

key

depressed.

b)

Hold

one key

down,

depress

next

higher

key

and

verify

that a retrigger

occurs.

+9V-

OV-

KEY

DOWN-*

-20

MSEC

KEY

UP—

FIGURE

4-4

TRIGGER

ATCOLLECTOR

OF

Q8

4.2.5

KEYBOARD

DRIFT

a)

Connect

DVM

to emitter

of

Q2

(Figure

4-3)

and

verify

the

keyboard

pitch

voltage

ranges

from

-4.50 V +100

mv

at

the

lowest

key

to

+4.50

V

+100

mv

at

the

highest

key.

b)

Verify

that

the

pitch

voltage

holds

steady

while

a

key

is

being

depressed

and

after

the

key

is

released.

In

neither

case

should

the

drift

exceed

25

mv

per

minute.

4.2.6

PREPARATION

FOR

OSCILLATOR A TUNING

(MAIN

BOARD

NO.

1)

a)

Place

all

tab

switches

and

slide

controls

up,

turn

all

potentiometers

counterclockwise

and

place

VIOLIN

tab

switch

down.

b)

Connect

a

jumper

between

the

collector

and

base

of

Q3

(Figure

4-3)

in

order

to

keep

IC10

on

and

thereby

eliminate

keyboard

control

voltage

drift.

c)

Hold

down

the

middle

B(,

key

(14

semitones

below

topmost

key)

for

oscillator

A

tuning.

d)

Center

the

rear

panel

TUNE

control,

connect

wiper

to

ground,

place 1 OCT

tab

switch

down

and

connect

DVM

test

leads

between

pin 6 of

IC8

(bot

tom

of

R14,

Figure

4-3)

and

ground.

Adjust

range

trimpot

R16

for

an

indication

of

0.0000

+0.0001

V.

4.2.7

OSCILLATOR

SCALE

1

OCT

tab

switch

down

2

OCT

tab

switch

down

a)

Adjust

REF

frequency

for

zero beat

with

oscillator

A.

Normally

the

REF

frequency

will

be

between

430

and

500

Hz

and

the

Synthesizer

fre

quency

will

be

two

octaves

lower

(nominally

117

Hz).

b)

Hold

down

high

Bb

key

(highest

black

key)

and

zero

beat

oscillator

A

with

REF

frequency

using

scale

trimpot

R17

(Figure

4-3,

Synthesizer

=*

233

Hz,

1

octave

below

REF

frequency).

4.2.8

OSCILLATOR A HIGH

FREQUENCY

COMPENSATION

1

OCT

tab

switch

up

2

OCT

tab

switch

up

a)

Adjust

REF

frequency

to

zero

beat

with

oscillator

A

(Synthesizer

=*

932

Hz, 1

octave

above

REF

frequency).

b)

Hold

down

the

high

B(,

key

and

zero

beat

oscillator

A

with

the

REF

frequency

using

the

oscillator

A

high

frequency

trimpot

(Figure

4-3,

tacked

on

to

the

left

of

R21).

Repeat

steps a and

b

several

times.

27

NOTE

Repeat

paragraphs

4.2.7

and

4.2.8

several

times

as

the

adjustments

interact,

i.e.,

each

time

the

scale

is

reset,

the

high

frequency

will

go

off

frequency

and

vice

versa.

The

process

converges

quickly

so

that

both

adjustments

can

be

accurately

set.

e)

Set

A/B

MIX

control to

vertical

so

that

the

pitch

of

oscillators

A

and B may

be

compared.

4.2.12

OSCILLATOR B SCALE

(Minitmoog

Only)

1

OCT

tab

switch

up

2

OCT

tab

switch

down

"B"

PITCH

control

full

CCW

4.2.9

OSCILLATOR A OCTAVE

TRANSPOSITION

1

OCT

tab

switch

down

2

OCT

tab

switch

down

a)

Adjust

REF

frequency

for

zero

beat

with

oscillator

A

(Synthesizer

=*

117

Hz, 2 octaves

below

REF

frequency).

b)

Place 1 OCT

tab

switch

up

and

zero beat

oscillator

A

with

REF

frequency

using

octave 1

adjust

trimpot

RIO

(Figure

4-3,

Synthesizer

=*

233

Hz,

1

octave

below

REF

frequency).

c)

Place 2 OCT

tab

switch

up

and 1 OCT

tab

switch

down

and

zero

beat

oscillator

A

with

the

REF

frequency

using

octave 2 adjust

trimpot

R21

(Figure

4-3,

Synthesizer

=*

466

Hz,

unison

with

REF

frequency).

4.2.10

OSCILLATOR A RANGE

a)

Zero

beat

oscillator

B

with

oscillator

A

using

range

trimpot

R504,

Figure

4-5

(oscillator

B

will

be

1

octave

lower

than

oscillator

A).

b)

Hold

down

highest

Bj,

key

and

zero

beat

oscillator

B

with

oscillator

A

using

scale

trimpot

R529,

Figure

4-5

(oscillator

B

one

octave

below

oscillator

A).

1

OCT

tab

switch

down

2

OCT

tab

switch

up

REF

frequency

exactly

466

Hz

M

X

zz

N

YY

L

K

J

P

R510

.

OCTAVE

R504

RANGE

R529

SCALE

R511

HI

END

a)

Set

range

trimpot

R16

(Figure

4-3)

so

that

oscillator

A

zero

beats

with

REF

frequency

(Synthesizer

=

466

Hz, unison

with

REF

frequency).

4.2.11

PREPARATION

FOR

TRACKING

OSCILLATOR

B

TO

OSCILLATOR A (Minitmoog

Only)

a)

Perform

paragraphs

4.2.6

through

4.2.10

to

tune

oscillator

A

before

tuning

oscillator

B

(located

on

oscillator

board

No.

5).

b)

Disconnect

jumper

between

collector

and

base

ofQ3.

c)

Hold

down

lowest

Bj,

key

using a wedge.

d)

Turn

off

REF

source

since

oscillator

B

will

be

tuned

by

making

it

track

oscillator

A.

FIGURE

4-5

OSCILLATOR B TRIMPOT

LOCATIONS

(BOARD

NO.

5)

4.2.13

OSCILLATOR B HIGH

FREQUENCY

COMPENSATION

(Minitmoog

Only)

1

OCT

tab

switch

up

2

OCT

tab

switch

up

"B"

PITCH

control

vertical

(in

deadband)

a)

Zero

beat

oscillator

B

with

oscillator

A

using

range

trimpot

R504,

Figure

4-5

(oscillators

A

and

B

in

unison).

b)

Hold

down

highest

Bb

key

and

zero

beat

oscillator

B

with

oscillator

A

using

high

end

trimpot

R511,

Figure

4-5

(oscillators

A

and B in

unison).

Repeat

steps a

and b several

times.

28

c)

Repeat

paragraphs

4.2.12

and

4.2.13

several

times

as

scale

and

high

end

adjustments

interact.

4.2.14

OSCILLATOR B OCTAVE

TRANSPOSITION

(Minitmoog

Only)

1

OCT

tab

switch

down

2

OCT

tab

switch

up

"B"

PITCH

control

vertical

(in

deadband)

a)

Zero

beat

oscillator

B

with

oscillator

A

using

range

trimpot

R504,

Figure

4-5

(oscillators

A

and

B

in

unison).

b)Set

"B"

PITCH

control

fully

clockwise

to

10

and

zero

beat

oscillator

B

with

oscillator

A

using

octave

trimpot

R510,

Figure

4-5

(oscillator

B

one

octave

above

oscillator

A).

NOTE

Allow a small

adjustment

latitude

by

tuning

oscillator

B

slightly

sharp

in

step b (approx

imately

2

Hz

beat

rate).

Thus

oscillator

B

will

be

in

tune

with

oscillator

A

slightly

before

the

control

reaches

full

rotation.

4.3

VOICE

CALIBRATION

4.3.1

PREPARATION

Set

the

following

controls

to

their

initial

position

as

follows:

Satellite

panel

marking

differences

are

in

parentheses.

4.3.2

SQUARE

WAVE

DUTY

CYCLE

a)

Observe

waveform

at

junction

of

R44

and

R119

(Figure

4-3).

b)

Depress

CLARINET

(REED

HOLLOW,

Satellite)

tab

switch

and

adjust

square

wave

adjust

trimpot

R47

for a symmetrical

square

wave

as

shown

in

Figure

4-6.

EXACTLY

50%

DUTY

CYCLE

FIGURE

46

SQUARE

WAVE

AT

JUNCTION

OF

R44ANDR119

4.3.3

BAND

PASS

FILTER

RESONANCE

(Q)

AND

CENTER

FREQUENCY

(Fc)

a)

Observe

waveform

at

source of

Q41

(Figure

4-3)

with

CLARINET

(REED

HOLLOW,

Satellite)

tab

switch

still

depressed.

b)

Depress 1 OCT

tab

switch

and C key one

octave

up

from

bottom

of

keyboard

and

adjust

band

width

and

center

frequency

trimpots

R130

and

R132

to

obtain

waveform

shown

in

Figure

4-7.

4

UNITS

1UNIT

700

USEC

(Fc:

R132)

4: 1 RATIO

(Q:

R130)

V^>»-^

FIGURE

4-7

BAND

PASS

FIL

TER Q AND

Fc

AT

Q41

SOURCE

4.3.4

LOW

PASS

FILTER

CUTOFF

FREQUENCY

(FL)

a)

Raise

all

tab

switches

and

depress

highest

key

on

keyboard.

b)

Set

VOLUME

slide

control

all

the

way

up

and

adjust

low

pass

cutoff

trimpot

R139

(Figure

4-3)

until

the

waveform

at

output

pin 6 of

IC22

(top

of

R162)

is

two

volts

peak-to-peak.

29

4.3.5

FILTER

CONTOUR

ATTACK

AND

DECAY

TIMES

a)

Depress

1OCT

tab

switch.

b)

Depress

MUTE

(BRASS

MUTE,

Satellite)

tab

switch

and

observe

filter

contour

at

the

source of

Q20

(Figure

4-3)

while

repeatedly

striking

C

key one

octave

from

bottom

of

keyboard.

c)

Adjust

filter

decay

and

attack

trimpots

R98

and

R105

until

the

filter

contour

matches

the

pattern

shown

in

Figure

4-8.

NOTE

It

may

prove

convenient

to

externally

trigger

the

oscilloscope

from

the

bottom

of

R64

for

paragraphs

4.3.5

through

4.3.7.

~

+1.7V-

ov-

-0.5V-

R105

ATTACK

R98

DECAY

200

MSEC ' 200

MSEC

FIGURE

4-8

FIL

TER

CONTOUR A T

Q20

SOURCE

4.3.6

LOUDNESS

CONTOUR

ATTACK

TIME

a)

Observe

waveform

at

junction

of

R165

and

R166

(Figure

4-3)

with

MUTE

(BRASS

MUTE,

Satellite)

and 1 OCT

tab

switches

still

down.

b)

Depress C key

one

octave

up

from

bottom

of

keyboard

and

adjust

amplitude

attack

trimpot

R174

to

match

the

attack

contour

shown

in

Figure

4-9.

+3.7V.

KEY

DOWN-*

0V-

^60-70.

MSEC

-20

MSEC

FIGURE

4-9

LOUDNESS

ATTACK A T

JUNCTION

OF

R165

AND

R166

4.3.7

LOUDNESS

CONTOUR

DECAY

TIME

a)

Lift

MUTE

(BRASS

MUTE,

Satellite)

tab

switch

and

depress

PIANO

(STRING

STRIKE,

Satellite)

tab

switch.

b)

Assure 1 OCT

tab

switch

is still

down

and

depress

C

key

one

octave

up

from

bottom

of

keyboard.

c)

Observe

waveform

at

junction of

R165

and

R166

(Figure

4-3)

and

adjust

amplitude

decay

trimpot

R190

for

the

decay

contour

shown

in

Figure

4-10.

J

FIGURE

4-JO

LOUDNESS

DECA Y ATJUNCTION

OF

R165

AND

R166

4.3.8

VOLTAGE

CONTROLLED

AMPLIFIER

BALANCE

a)

Lift

PIANO

(STRING

STRIKE,

Satellite)

tab

switch

and

short

junction

of

R149

and

C30

(Figure

4-3)

to

ground.

b)

Set

VOLUME

slide

control

at

maximum

and

connect

oscilloscope

probe

to

top

of

R162.

c)

Hit

and

release

a

key and

adjust

VCA

balance

trimpot

R160

until

a

minimum

click

or

thump

is

heard

and

step

waveform

at

top

of

R162

does

not

exceed

lOmv.

4.3.9

VIBRATO

DEPTH

a)

Set

vibrato

depth

trimpot

Rl

fully

CCW.

I

30

SECTION

5

OPERATING

CONTROLS,

INDICATORS

AND

CONNECTORS

Satellite

Synthesizer

panel

marking

differences

are

shown

in

parentheses.

PANEL

MARKING

REF

DESIG

FUNCTION

FILTER

ATTACK

(FILTER

CONTOUR)

Slide

Control

FILTER

DECAY

(FILTER

COLOR)

Slide

Control

FILTER

BRIGHTNESS

(FILTER

EMPHASIS)

Slide

Control

MODULATION

RATE

Slide

Control

MODULATION

DEPTH

Slide

Control

R7

R8

R9

RIO

Rll

GLIDE

Slide

Control

VOLUME

Slide

Control

POWER

Tab

Switch

and

Indicator

Light

R12

R13

SW21

"B"

PITCH

\

Variable

Resistor/

A/BMIX

Variable

Resistor/

WMinitmoog

(

Only)

Controls

amount

of

time

it

takes

for

the

bright

ness

to

reach a peak; 0 is

the

normal

setting,

-4

indicates

the

longest

attack

and

+4

the

shortest

attack

times.

Controls

amount

of

time

it

takes

for

the

bright

ness

to

die

away

on

most

voices;

0

is

the

normal

setting,

-4

indicates

the

longest

decay

and

+4

the

shortest

decay

times.

Determines

voice

clarity

from

dull

to

bright

sounds.

Varies

rate

of

modulation

from

approximately

one

per

second

at 0 to a buzz

rate

at

10.

Adjusts degree

or

intensity

of

modulation.

With

MODULATION

VIB

tab

switch

depressed,

increasing

MODULATION

DEPTH

corresponds

to

periodic

frequency

deviation

that

increases

from

zero

to

more

than

one

octave.

With

MODULATION

TREM

tab

switch

depressed,

increasing

MODULATION

DEPTH

corresponds

to

greater

periodic

timbre

variation.

Adjusts

keyboard

glide

time

from

note

to

note

from 0 to 4 seconds

when

GLIDE

tab

switch

is

depressed.

Adjusts

Synthesizer

output

level

over a range

of

30dB.

Controls

primary

power

supplied

to

instrument.

Red

indicator

light

indicates

when

POWER

tab

switch

is

depressed

and

primary

power

is

supplied

to

the

instrument.

Varies

pitch

of B tone

producing

oscillator

over

a

two

octave

range.

Controls

mixing

of A and B tone

source

oscillator

outputs.

A

only

or B only

occur

at

the

CCW

and

CW

extremes

of

rotation,

respectively.

31

OPERATING

CONTROLS,

INDICATORS

AND

CONNECTORS

(Cont.)

32

OPERATING

CONTROLS,

INDICATORS

AND

CONNECTORS

{Cont.)

PANEL

MARKING

REF

DESIG

FUNCTION

SUST

Tab

Switch

MUTE

(BRASS

MUTE)

Tab

Switch

Tab

Switch

TUNE

Variable

Resistor

SW13

SW12

R237

When

depressed,

allows

note

to

die

away

more

gradually

after

key

is

released.

When

depressed,

approximates

a

"wah-wah"

muted

brass

voice

starting

with an

emphasis

on

the

lows,

moving

to

the

highs

and

returning

each

time a key

is

depressed.

When

depressed,

keyboard

produces

the

sounds

of a trumpet,

trombone

or

tuba

by

depending

on

various

other

controls.

When

depressed,

keyboard

produces

the

sounds

similar

to

that

of a double

reed.

In

the

top

octave,

the

sound

is

of

an

oboe.

In

the

lower

octaves,

the

sound

of a bassoon

is

approximated.

When

depressed,

keyboard

produces

the

hollow

reed

sound

and

soft

attack

of

the

traditional

clarinet.

When

depressed,

keyboard

produces

the

bright

reed

sounds

of a saxophone.

When

depressed,

keyboard

simulates

the

bass

sound

characteristic

of

the

Taurus

Synthesizer.

When

depressed,

keyboard

produces

a

gentle

voice

with a slow

attack

simulating

the

sounds

of a violin.

When

depressed,

keyboard

produces

a

plucked

string

voice

with a lingering

decay

for

creating

guitar

or

harpsichord

effects.

When

depressed,

keyboard

produces

a

percussive

struck

string

voice

similar

to a piano.

When

depressed,

produces

a

typical

synthesizer

sound.

When

depressed,

produces

an

interesting

sound

similar

to

that

of

an

electric

bass

guitar.

This

versatile

voice

provides

a

wide

variety

of

timbre

changes

which

produce

many

popular

electronic

Moog

sound

effects

when

depressed.

Adjusts

pitch

of

Synthesizer

to

match

the

pitch

of

another

instrument.

33

OPERATING

CONTROLS,

INDICATORS

AND

CONNECTORS

(Cont.)

SECTION

6

KEYBOARD

MAINTENANCE

AND

ADJUSTMENT

6.1

CONTACTS

6.1.1

DIRTY

CONTACTS

The

J-wire

switch

contact

to

the

buss

bar

may

become

dirty

or

corroded.

If

so,

use

ordinary

rub

bing

alcohol

(isopropanol)

on a cotton

swab

to

clean

the

contact

area.

Do

not

spray

contact

cleaner

onto

the

key

contacts

or

use

abrasives

(emery

paper

or

burnishing

tools)

as

they

will

remove

the

gold

plating.

Be

careful

not

to

bend

the

J-wires

(fine

whiskers).

Stubborn

cases

may

require

cleaning

with a nonabrasive

rubber

eraser.

If

the

contact

area

has

been

damaged,

rotate

the

buss

bar

or

J-

wire

or

gently

bend

the

J-wire

laterally

to

contact

a

new

portion

of

the

buss

bar.

34

CAUTION

Do

not

touch

J-wires

or

buss

bar

with

bare

fingers

as

salty,

oily

finger

prints

will

eventually

cause

corrosion

and

dust

collection

resulting

in

inter

mittent

operation.

6.1.2

CONTACT

HEIGHT

Dirty

contacts

are

revealed

by

improper

trig

gering

of

notes.

Triggering

problems

may

also

occur

if

the

contact

height

(the

distance

tip

of

key

travels

downward

before

the

note

sounds)

is

set

too

high

(i.e.,

makes

contact

too

soon).

Black

keys

should

make

contact

between

1/8

and

3/16

inch

of

down-

ward

travel

and

white

keys

between

3/16

and

1/4

inch.

If

necessary,

rebend

by

gently

massaging

the

portion

of

the

wire

between

the

actuator

and

the

attachment

point.

The

contact

must

make

before

the

key

bottoms

on

the

touch

sensor

assembly.

6.2

KEYS

6.2.1

CLANKING

Keys

will

clank

or

thump

if

the

tails

hit

the

case

on

the

down

stroke.

This

problem

can

be

repaired

by

gluing

a thin

spacer

such

as a 1/16

inch

thick piece

of

wood

to

the

case

immediately

above

the

plastic

strip

over

the

key

pivots.

The

case

will

be

forced

away

from

the

keys

upon

reassembly

and

clanking

should

cease.

6.2.2

STICKING

OR

SLUGGISH

FEEL

Check

the

pivot

for

being

too

tight.

Rotate

the

pivot

tab

about

the

vertical

axis

by

bending

a

few

degrees

with a pair

of

pliers.

Make

certain

the

key

tails

are

not

rubbing

on

the

back

of

the

case

necessitating

the

removal

of

some

of

the

wood

with

coarse

sandpaper.

Keys

near

either

end

of

the

key

board

may

stick

because

the

hex

head

screw

that

fastens

the

rear

mounting

brackets

to

the

keyboard

frame

does

not

have

its

flats

aligned

vertically.

In

this

case,

the

screw

head

will

rub

against

the

key

return

springs

and

cause

the

trouble.

6.2.3

LEVELING

If a key

does

not

return

to

the

same

height

as

its

neighbors,

the

key

leveling

tab

located

inside

the

front

end

of the

metal

body

of

the

key

must

be

bent

up

or

down

as

required.

Remove

the

key

screw

so

the

ivory

comes

off

and

reposition

the

tab

using

the

keyboard

adjusting

tool,

part

number

962-043031-001.

6.3

TOUCH

SENSOR

6.3.1

SENSOR

MOUNTING

The

touch

sensor

assembly

is

mounted

to

the

keyboard

frame

by 5 studs

attached

to

the

sensor

assembly.

The

height

of

the

assembly

must

be

set

so

that

the

keys

will

bottom

on

the

sensor

assembly

and

not

on

the

key

leveling

tabs.

The

5

studs

are

locked

into

position

by 10

nuts

on

either

side

of

the

keyboard

frame.

The

sensor

is

intentionally

warped

by

the

extreme

end

studs

when

mounted

so

that

its

ends

are

approximately

1/16

inch

further

away

from

the

keyboard

frame

than

its

center.

This

must

be

accomplished

before

the

keyboard

is

installed

in

the

chassis.

The

warp

ing

must

be accomplished

so

that

touch

sensitivity

for

keys

at

the

ends

of

the

keyboard

is

the

same

as

that

for

the

keys

in

the

center.

If

this

is

not

accomplished,

the

center

keys

will

be

overly

sen

sitive

while

the

end

keys

will

not have

enough

response.

6.3.2

ADJUSTING

SCREWS

Two

slotted

screws

set

the

pressure

with

which

the

rod

bears

against

the

foam

pad.

Adjust

these

screws

as

follows:

1

OCT

and 2 OCT

tab

switches

up

VIOLIN

and

PITCH

tab

switches

down

TOUCH

SENSE

variable

resistor

full

clockwise

Play over

the

entire

keyboard

"with a normal

light

playing

touch.

If

unwanted

pitch

bending

occurs,

tighten

slotted

screws

by

turning

counter

clockwise

until

bending

occurs

only

when

extra

pressure

is

applied

to

the

keys.

If

the

screws

are

over

tightened,

the

sensor

will

not

be

responsive

enough.

The

pitch

should

bend

upward

at

least

a

fifth

(7

semitones)

for

any

key

pressed

down

heavily.

Especially

check

the

keys

near

each

end

of

the

keyboard

as

they

nor

mally

will

be

less

responsive.

If

necessary,

loosen

screws

slightly

by

turning

clockwise

and

recheck

for

over

sensitivity.

6.3.3

TOUCH

SENSOR

INTERMITTENT

OPERATION

WHEN

DEPRESSED

OR

TOUCH

SENSOR

DEAD

This

trouble

may

be

due

to

open

contacts

between

the

shielded

cable

and

either

the

con

ductive

nylon

(snap

fastener)

or

the

touch

bar

(No. 6 screw

in

end)

or

there

may

be a short

between

the

touch

bar

and

the

nylon.

Shorts

may

occur

around

the

two

holes

in

the

rod

through

which

the

35

adjusting

screws

pass

or

at

the

end

of

the

rod

if

the

No.

6

screw

touches

the

nylon.

Repair

these

shorts

by

sticking

a

small

piece

of

Scotch

No.

156

2

mil

mylar

tape over

the

area

of

the

short.

Burn

a

hole

in

the

tape

with a soldering

iron

for

the

adjusting

screw.

If

the

nylon

is

frayed,

look

for

a strand

touching

either

end

of

the

buss

bar

caus

ing a short

circuit.

Repair

this

by

burning

off

the

strand

with a soldering

iron.

6.3.4

OTHER

DIFFICULTIES

If

one,

several

or

all

of

the

keys

are

inoperative,

make

certain

the

wiring

harness

is

not

pushed

into

the

key

contacts.

In

addition,

check

for a strand

of

frayed

conductive

nylon

contacting

the

key

switches

causing

nonf

unctioning

or

crazy

operation.

If

when

bending

pitch,

the

pitch

drifts

down

at

an

objec

tionable

rate

while

the

key

is

pressed

down

fully,

replace

IC402.

(IC402

is a factory

selected

part

requiring

a

CA3080

with

low

output

leakage.

Try

several

CA3080s

until

one

with

the

proper

charac

teristics

is

located.)

Sometimes

the

audio

output

may

die

out

completely

when a key

is

pressed

down

hard.

This

trouble

may

be

caused

by

one

of

the 5 mounting

studs

contacting

the

top

of a

socketed

CA3080

metal

can

on

the

main

board.

If

this

occurs,

shorten

the

CA3080

leads,

studs

or

both

as

required.

36

SECTION

7

TROUBLESHOOTING

GUIDE

The

procedures

that

follow

generally

apply

to

both

Synthesizers

except

where

the

Oscillator

Board

5

and

Touch

Sensor

Board 4

are

mentioned.

These

components

are

used

only

on

the

Minitmoog.

An

aid

in

control

selection

is

presented

in

Section

5

indicating

the

different

panel

markings

for

identical

controls.

37

TROUBLESHOOTING

GUIDE

(Cont.)

SYMPTOM

PROBABLE

CAUSE

7.2

SOUND

CHAIN

Set the

following

controls

as

follows

for

all

sound

chain

troubleshooting

procedures.

All

tab

switches

up

except

VIOLIN

tab

switch

down.

All

slide

controls

at

zero

position

except

VOLUME

slide

control

at

10.

All

front

panel

rotary

controls

full

counterclockwise

position.

A.

No

sound

and

POWER

indicator

light

off.

B.

No

sound,

POWER

indicator

light

on

and 9 volt

power

supplies

operating

properly.

C.

Intermittent

sound

or

sound

dies

when

key

is

depressed

firmly.

D.

Neither

oscillator

A

or

B

operating.

1.

115

VAC

wiring

faulty.

2.

POWER

switch

SW21

defective.

1.

Connect

oscilloscope

probe

to

emitter

of

Q46

and

verify

oscillator

A

is

operating

properly.

2.

Connect

oscilloscope

probe

to

pin 6 of

IC501

and

verify

oscillator

B

is

operating

properly.

3.

If

both

oscillators

are

operating

properly,

set

A/B

MIX

control

vertical

and

check

waveforms

on

pins Z (oscillator

A)

and

ZZ

(oscillator

B)

of

board

No. 5 (Figure

4-5).

Levels

should

cross

fade

as

A/B

MIX

control

is

rotated.

Trouble

would

most

likely

be

caused

by

faulty

wiring

from

pins

S,

X,

Y, Z or

ZZ.

If

only

oscillator

A

is

not

operating,

trouble

may

be

in

waveform

selector

circuit.

If

proper

waveforms

are

observed

on

pins Z and

ZZ,

proceed

to

step

4.

4.

Check

band

pass

filter

output

waveform

at

source

of

Q41.

Signal

level

should

be

approximately

300

mv

peak-to-

peak.

No

output

indicates

trouble

is

in

band

pass

filter

section.

If

proper

output

is

observed,

proceed

to step

5.

5.

Check

low

pass

filter

output

waveform

at

pin 1 of

IC20

with a key

depressed.

Signal

level

should

be

approxi

mately

400

mv

peak-to-peak.

If

not,

trouble

is

in

the

voltage

controlled

filter

or

amplifier

(IC19

or

IC20).

If

proper

waveform

is

observed,

proceed

to

step

6.

6.

Check

waveform

at

pin 6 of

IC22

while

holding

a

key

down.

Signal

level

should

be

approximately

3

volts

peak-

to-peak.

If

normal,

trouble

is

in

output

wiring,

R236,

J3,

J4

or

associated

circuitry.

Otherwise

IC22

or

associated

circuitry

is

faulty.

1.

Keyboard

shorting to

top

of a CA3080

integrated

circuit

can.

Shorten

leads

or

touch

sensor

mounting

studs.

2.

Harness

wiring

or

rotary

control

lug

shorting

to

front

panel

extrusion.

1.

Faulty

exponential

current

source

IC11

or

IC21.

2.

IC8

or

associated

dc

summer

circuitry

faulty

(possible

shorted

summing

resistor).

3.

Resistor

R14

broken.

4.

Improper

input

to

dc

summer

input

resistors.

38

TROUBLESHOOTING

GUIDE

(Cont.)

SYMPTOM

PROBABLE

CAUSE

7.2

SOUND

CHAIN

(Cont.)

E.

No

oscillator

B

output,

oscillator

A

operating

properly.

F.

No

oscillator

A

output,

oscillator

B

operating

properly.

G.

No

waveshaper

output.

H.

Band

pass

filter

will

not

pass

signal.

I.

J.

K.

Band

pass

filter

current

sources

at

fault.

Low

pass

VCF

and

VCA

do

not

pass

signal

(no

signal

on

pin 1 of

IC20).

L.

Low

pass

VCF

operating

properly

(proper

signals

at

pins 7 and

10

of

IC20)

but

VCA

has

no

output

(pin 1

of

IC20).

VCA

operating

properly

but

has

no

output.

1.

IC501,

IC502,

Q501,

Q502

or

Q503

defective.

2.

Input

wire

to

board

No. 5 broken.

3.

Resistor

R501

broken.

4.

Connector

pin

M, R or P shorted.

5.

IC11

defective.

1.

IC12,

Q43,

Q44,

Q45

or

Q46

defective.

2.

Open

OSC A HI

END

trimpot.

3.

Capacitor

C38

shorted.

1.

IC13,

Q47

or

Q48

defective.

2.

Resistor

R47

open.

3.

Faulty

wiring

to

pin

D6

of

resistor

matrix.

1.

Ground

collectors

of

Q38

and

Q39.

If

signal

still

does

not

pass,

trouble

is

in

IC15, IC16,

IC17,

Q41

or

Q42

or

associated

circuitry.

If

signal

passes

the

filter,

check

filter

control

current

sources.

1.

Remove

one

short

and

then

the

other

to

determine

which

transistor

pair,

Q37

and

Q38

or

Q39

and

Q40,

is

faulty.

2.

Ground

both

transistor

bases

of

the

faulty

pair

and

observe

if

signal

passes

(collectors

not

shorted).

If

signal

passes,

the

fault

lies

in

the

summing

network,

matrix

or

matrix

interconnecting

wiring.

Otherwise

the

transistor

pair

or

trimpot

is

at

fault.

1.

Short

pin

14

of

IC19

to

ground.

If

signal

passes,

the

fault

is

in

either

the

filter

contour

circuitry

or

the

transistor

the

collector

of

which

is

tied

to

pin

14.

If

signal

still

does

not

pass,

proceed

with

step

2.

2.

With

pin

14

of

IC19

still

shorted

to

ground,

measure

waveform

at

pins 7 and

10

of

IC20.

Signal

at

each

pin

should

be

approximately

10

mv

peak-to-peak

(about

hah'

the

20

mv

peak-to-peak

observed

at

pin 2 of

IC19).

If

signal

is

present,

VCF

is

operating

properly

arid

the

problem

lies

within

the

VCA.

If

signal

is

not

present,

trouble

is

in

IC19.

1.

Hold

down a key and

check

that

voltage

at

pin

12

of

IC20

holds

at

approximately

+3.5

VDC.

If

voltage

holds,

trouble

is

in

IC20,

R164,

VOLUME

control

R13

or

wiring

from

R164

to

R13.

If

voltage

at

IC20

does

not

rise,

the

amplitude

envelope

generator

is

not

functioning.

1.

Trouble

is

in

IC22,

C32,

LEVEL

ADJUST

control

R238

or

output

wiring.

39

TROUBLESHOOTING

GUIDE

(Cont.)

41

SECTION

8

MODIFICATIONS

8.1

SERVICE

BULLETIN

802

This

Service

Bulletin

was

issued

and

is

included

in

this

manual

to

avoid

future

maintenance

because

of

defective

or

intermittent

touch

sensor

bar.

This

condition

occurs

because

of a chemical

reaction

between

the

foam

and

conductive

nylon

material.

8.2

TOUCH

SENSOR

BAR

(Minitmoog

Serial

Numbers

below

2144)

Rebuilt

touch

sensor

bars

are

available

under

part

number

997-043976-001.

It

is

estimated

to

require

1

hour

to

perform

the following

procedures:

1.

Remove

the

touch

sensor

from

the

unit

by

removing

the

bottom

cover

and

unscrewing

four

screws

(Figure

8-1)

to

disassemble

the

unit

to

the

extent

shown

in

Figure

8-2.

2.

Remove

the

five

nuts

from

the

captive

screws

(Figure

8-2)

securing

the

top

support

to

the

unit

and

remove

the

support.

3.

Unscrew

the

two

screws

that

attach

the

sensor

to

the

top

support

(Figure

8-3).

4.

Remove

and

discard

the

conductive

nylon

material

and

the

double

sided

tape

(Figure

8-4)

being

careful

to

avoid

damaging

the

foam

pad.

FIGURE

8-1

DISASSEMBL Y OF

MINI

TMOOG

42

R

EMOVE 5 NUTS

ADJUSTMENT

SCREW

;

RIGHT

SIDE

FIGURE

8-2

MINITMOOG

DISASSEMBLED

5.

Apply

two

strips

of

double

sided

tape

to

completely

recover

the

foam

pad

(Figure

8-5).

30

6.

Install

a

drain

wire,

No.

30

AWG

gauge

(No.

•0

buss

wire),

generally

centered

along

the

length

of

che

touch

sensor

bar.

However,

carefully

route

the

wire

around

the

two

mounting

holes

and

allow

sufficient

excess

wire

to

extend

beyond

the

right

side

of

the

bar

to

permit

soldering

the

wire

to

the

cable

braid

after

the

touch

sensor

bar

is

installed.

The

wire

should

be

slightly

less

than

flush

on

the

left

side

of

the

sensor

bar.

FIGURE

8-3

SENSOR

REMOVAL

43

FIGURE

8-4

SENSOR

REMOVED

FROM

TOP

SUPPORT

7.

Install

new

conductive

nylon.

8.

Add

mylar

tape

insulating

pads

over

the

nylon

material

at

the

two

mounting

holes

(Figure

8-6).

9.

Also

wrap

the

end

of

the

touch

sensor

bar

with

mylar

tape

at

the

point

where

the

drain

wire

extends

beyond

the

end

of

the

bar

(Figure

8-6)

to

prevent

shorts

after

connection

in

the

circuit.

FIGURE

8-5

MODIFICA

TtON

MA

TERIAL

44

10.

Remove

the

snap

fastener

from

the

shield

braid

in

the

Minitmoog.

11.

Install

the

touch

sensor

bar

in

the

unit

and

solder

the

drain

wire

to

the

shield

braid

of the

interconnecting

cable.

12.

Mechanically

reassemble

the

touch

sensor

bar

in

the

reverse

order

of

disassembly.

NOTE

The

drain

wire

should

be

positioned

to

the

left

side

when

reassembling

the

unit.

V

FIGURE

8-6

TOUCH

SENSOR

BAR

REASSEMBLED

8.3

INSTALLATION

OF

NEW

OR

REBUILT

TOUCH

SENSOR

BAR

1.

Remove

case.

2.

Set

unit

on

rear

panel

using

support

blocks.

3.

Remove

bottom

access

cover.

4.

Compress

touch

sensor

bar

by

tightening

all

adjusting

screws.

5.

Remove

five

mounting

nuts.

6.

Disconnect

wiring

to

touch

sensor

bar

and

dislodge

bar

from

keyboard

"L"

channel,

ensuring

all

mounting

screws

are

clear

of

mounting

holes.

7.

Slide

touch

sensor

bar

out

of

right

side

of

unit.

8.

Reassemble

in

reverse

order

using a new

or

rebuilt

touch

sensor

bar.

45

SECTION

9

SELECTED

REPLACEMENT

PARTS

LIST

MINITMOOG

AND

SATELLITE

MISCELLANEOUS

SELECTED

REPLACEMENT

PARTS

LIST

46

MAIN

PRINTED

CIRCUIT

BOARD

SELECTED

REPLACEMENT

PARTS

LIST

47

MAIN

PRINTED

CIRCUIT

BOARD

SELECTED

REPLACEMENT

PARTS

LIST

(Continued)

REF

DESIG

PART

NUMBER

CROSS

REF

NO.

DESCRIPTION

Q1

Q2,Q4,Q6,Q7,

Q9thruQ15,

017,025,026,

Q27,Q31,Q34,

Q35,Q36,Q43,

044,046,047,

Q48.Q50

Q3,Q5,O8,

O16,Q19,Q21,

024,028,029,

Q30,Q33,Q37

thru

Q40.Q49

020,032,041,

Q42.Q51

022,023

Q45

991-041062-001

991-041052-001

991-041051-001

991-041064-001

991-041055-001

991-041063-001

TRANSISTORS

86-5150-2

86-5115-2

86-5149-2

86-5148-2

86-5124-2

86-5096-2

86-5147-2

86-5146-2

86-5096-2

86-5151-2

PNP,

TIS93

PNP,

2N3906

NPN,

2N3904

FET.

2N4303

FET,

E112

PNP,

2N4402

MINITMOOG

TOUCH

SENSOR

BOARD

NO.

4

SELECTED

REPLACEMENT

PARTS

LIST

MINITMOOG

OSCILLATOR

BOARD

NO.

5

SELECTED

REPLACEMENT

PARTS

LIST

49

CONTROL

BOARD

(POWER

SUPPLY)

SELECTED

REPLACEMENT

PARTS

LIST

SECTION

10

BLOCK

AND

SCHEMATIC

DIAGRAMS

FIGURE

TITLE

PAGE

10-1

10-2

10-3

10-4

10-5

10-6

10-7

10-8

Minitmoog

Schematic

Diagram

51

Minitmoog

Block

Diagram

52

Minitmoog

Printed

Circuit

Board

Assemblies

52

Minitmoog

Touch

Sensor

Board

Assembly

No. 4 Schematic

Diagram

53

Minitmoog

Oscillator

Board

Assembly

No. 5

Schematic

Diagram

53

Satellite

Schematic

Diagram

54

Satellite

Printed

Circuit

Board

Assemblies

55

Satellite

Block

Diagram

.'

56

50

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FIGURE

10-1

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51

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FIGURE

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FIGURE

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55

MINITMOOG

AND

SATELLITE

SYNTHESIZERS

MOOG

MUSIC

INC.

2500

Walden

Avenue.

Buffalo,

New

York

14225

NORLIN

MUSIC

INSTRUMENTS

LIMITED

51

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Blvd.,

Scarborough.

Ontario,

Canada

MIP

2N6

NORLIN

MUSIC

SERVICES

B.V.

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Zuidzijde

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H.

J.,

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The

Netherlands

PRINTED

IN

U.S.A.

COPYRIGHT -1979

993-041990-002

T.G. -10/79 -1M

MOOG

MUSIC

INC.