Curtis Computer kb4900 Owner's Manual

k:I3——4l‘9(3(3

ASCII,

BAUDOT

AND

MORSE

KEYBOARD

ONNER’S

MANUAL

TABLE OF

CONTENTS:

Description

. . . . . .

.................. 3

Commands . . . . . . .

.... . . . . . . . . . . . . .

... 5

Specifications.....................

7

Dperation.......

. . . . . .

............. 9

General

Operation..................

12

Operation

on

12v. . . . . . . . . .

......... 15

Circuit

Functions . . . . . . . . . .

........ 15

Ca1ibration..... . . . . . . . . . . .

........ 15

In Case

of

Difficulty

. . . .

.......... 16

Limited

Warranty.......

. . . . . . . . . . ..

16

Program

Changes

and

Revisions...... 16

Assembly Drawings

and

Schematics... 17

Code Practice

Lists...... . . . . . . . . ..

Appendix

A

CIRCUITS AND EPROM

CONTENTS

COPYRIGHTED

1980,

CURTIS ELECTRO

DEVICES, INC.,

BOX

4090,

MOUNTAIN

VIEW,

CA 94040

*

3.8 *'#’* # *

*I*

]IhJ1‘F?C3I)LJCZ1’1ZC)rJ * X *»#i* #.I:# t 1

Your KB—490O is a

product

of the

computer

age.

Unlike its

predecessors

the KB—42OO AND

KB-4800,

this unit does not use discrete dedicated

parts

to

perform

its function.

Instead,

it

employs

an

"all

purpose"

IC called an

integrated microprocessor.

This

device

does

nothing

itself,

however,

when

provided

with a

list of

instructions,

it will

carry

them

out

and in so

doing,

accomplish

the

objectives

of the

programmer

who devised the set of instruct‘

ions.

The KB—4900 uses a

microprocessor

called the 5035

(developed by

the

Intel

Corporation).

The 9035 contains an 8-bit

central

processor

unit

(CPU),

512 bits of

random access

memory

(RAM),

27

input—output

lines (1/0) and

an B~bit timer/event

counter.

For

instructions,

we use the

2732 (Ultra-Violet) Eraseable

Programmable

Read—Dn1y Memory

(EPRDH). It can

contain

as

many

as

4,096

individual

instructions

composed

of

32,768

individual bits. The

sending

buffer and

message storage

are

implemented

in another

powerful

IC,

the 2114. This

Random—Access

Memory

(RAM) will

store

512

Esbit

bytes

in its

4,096

read‘

write

storage cells,

and

last,

but not

least,

the

venerable 9044

single

chip

keyer

IC

provides

the Morse

code

generation

in

order to free the

processor

for more

complicated

tasks. For

those

of

you

interested in

statistics,

the

circuitry

in

the KB—4900 contains

approximately

100,000

individual

transistors.

The

program

for

the KB—4900 uses most

of the

4,096

instructions

possible

from the

2732. From

a

library

of 90

individual instructions

recognized by

the

microprocessor,

the

program

is

built-up

into

a

sequence

that

provides

the

function of

the KB—4900.

The

microprocessor

winds its

way through

the

program

at the

rate of

400,000

instructions

per

second.

And,

while it looks

as

though

things

are

being

done all at

once,

in

reality they

are

being

done

one—by—one.

The

processor

does

everything serially except

that it handles

all data in

groups

of

eight binary digits

called

bytes.

The

processor

is

unbelievably busy

while the

unit is

operation,

executing

the

prescribed

program

at the 400 KHZ

rate. It is not

unlike a

juggler

keeping

many plates

spinning

at

one time.

Though

we have

only

one

juggler,

there is a whole

lot of

activity

going

on. In the

case of the

KB«4900,

it

may

be

sending

DU,

accepting

new

key

inputs,

assigning spaces

in

the

sending buffer, unloading

the

sending

buffer at

some other

point, running

the buffer

meter, running

the

speed

meter,

holding

the

PTT line

down,

watching

for buffer

overflow, keeping

track of the

time.

incrementing

the serial

number,

and

scanning

the

keyboard

for new

commands....400,000

times a

second without mistakes!

The

program

for

the KB—4900

consists of 78

pages

of

single spaced

text. It

took

nearly

six

months

of

writing,

testing

and

debugging

to

get

the

program ready.

we

hope you

enjoy using

the

system

as much

as

we

enjoyed

designing

it,

If

you

have

suggestions

on how we

might

improve

the

unit,

don’t

hesitate to

call or

drop

a line.

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Hanual..............

. . . . . .........

. . . . . . . . ...Revised

01-23-81

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ISENDS

XSENDS ISENDS ISENDS

XSENDS KSENDS

MORSE

FROH KEYBOARD

HORSE FROM PADDLE

KEY,

MANUAL KEY

BAUDOT

CODE FROM KEYBOARD

ASCII CODE FROM KEYBOARD

I)EE£3(3F?

I F31'I EJFJ-

OR BUG

TRUE RANDOM

HORSE FDR CODE PRACTICE

PSUEDO RANDOM MORSE IN 8~l5OO CHAR.

LISTS OF 5-LETTER

GROUPS N/ANSWERS

Sends Morse

code from the

keyboard

or

from an external

paddle

key

at

any speed

selected

by

the

speed

control.

Analog

controls

(potentiometers)

sidetone

pitch

and sidetone volume.

An

analog

meter readout of buffer

status

the

fullness of the

sending

buffer which

(overflow

lamp

and

pitch change

on

Horse

A "BUFFER HOLD" function allows break—in

key

is

operational during

the hold.

An

analog

meter readout is also

provided

readout.

This is calibrated from 5 to B0

either

keyboard, paddle

initiated

keying

are also

provided

for

weight,

continuously

indicates

can

contain as

many

as 256

characters.

signals

nearly

full buf#er)

operation.

The

paddle

for Morse code

speed

upm

and is effective

for

or random code

practice.

Push—to—talk control is

provided

for transmitter

switching

in all modes.

PTT release is

delayed

0.5

Special prosigns

AS,SK,BT,AA,KN,

KA

plus

commercial.

Four

programmable message

memories

(A,B,E

&

D)

seconds {or convenience.

most

European

and

are

provided.

These

can consist of one to four

messages

whose total is 256

characters.

Messages

are called

via the

sending

buffer.

partitioned, meaning

that “B”

imum use of the

memory

storage.

The memories

may

be

"chained"

Memories

always

starts wherever

The {our memories are soft

"A" ends to make

max-

"C. and "D"

via the buffer.

(Warning lamp

for overflow

during

load is

provided)

(3)

follow in

the same manner.

Automatic bu11t'in

messages

are

provided

as follows:

CG CG DE

(message

A)

(i.o. "KbKU")

CD

TEST DE

(message

A)

DE

(message

A) (This is the "ID"

key)

QRZ

(message

A)

(Note that these are

appended by programmable

message

“A“)

Two

key

lockout

operation

of

keyboard prevents

lost

characters

during

"burst"

typing.

A "DELETE"

key

allows

correction of errors

prior

to transmission.

An automatic

incrementing

serial number from 0 to 9999 is available

for insertion into

the

sending

buffer or the

message

memories for contests

which

require

sequential numbering. Leading

zeros are not transmitted.

A

repeat

Function allows

repetition

of

any

o¥ the Four

message

memories

a5ter a

presettable

period

of from 1 to 99 seconds.

9 real—time clock

option

allows

generation

of a time transmission

(24-hour

Format,

1.e. 21:42) in

Morse,

Baudot or ASCII. Time can be

inserted in the

sending

buffer or

any message memory.

Time is sent

as 21R24 in

Morse,

21:24 in ASCII and Baudot.

BAUDOT

CODE:

Baudot (S—level) TTY code is transmitted ¥rom

the

keyboard

at

50

wpm

standard

speed.

(45.45

baud)

Both RTTV

and

Cw

ID are

provided

("ID“

key)

High voltage

&OmA.

loop keying

transistors are built into the unit.

Provisions are made for

mixing

receiver audio and

keyer

sidetone For convenient

monitoring.

Carriage return,

line feed and "LTRS" are sent

automatically

after 63 characters and a

space

have occurred on a line. After 70

characters,

the Function is initiated without

any space being present.

This makes nice

looking copy

at the

receiving end,

with the

carriage

return not

breaking

words.

Also this

frees the

operator

4rom

worrying

about

the

carriage

return.

All

up

and down shift is handled

automatically.

In

addition,

a

dounshift occurs on

every space

to

quickly

clear

any

garbles

in

recept-

ion.

As

with Horse

transmission,

included are the

sending buf§er,

the

programmable message memories,

the

automatic

message sequences

plus

the

"DELETE" function and

KUS

(Key-DperatedASwitch)

control.

ASCII:

Same as

Baudot above

except

that Functions

involving up

and

down

shift (FIGS and LTRS) are not

required.

Transmission

speed

is 110

baud.

Both

upper

and lower case are

generated (upper

case

by shifting)

G "CAPS LOCK“ function

allows

transmission of

capital

letters

only.

(4)

NURSE PRACTICE:

Mode 1: Random

length groups

of random

characters

are sent

in a

never

repeating sequence

at the

speed

selected

by

the

speed

control. Extra

spacing

between characters can be selected

for easier

study

when

trying

to

make

large speed

increases.

Mode 2: Psuedo random

five character

groups

are

sent, however,

unlike the

above

true random

generation,

this second mode

sequence

is

always

the

same

and answer lists can

be

provided.

There are

eight

lists available and are

called

by

placing

the number "1"

through

“E” in

message memory

"A". If

any

other character is

placed

in

message

memory "A",

the

mode 1 random Horse

will be sent. The

sending stops

at the

end of each list. To

restart,

use a

system

reset and restart the

program.

with

both

modes, you

can

insert extra

space

between letters

by pressing

the "CTRL"

key

followed

by

the "5"

key.

Also,

with both

modes, you

can eliminate numbers and

punctuation

by

placing

an "N" after the “R” or number "i" thru "8" in

message memory

"A".

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I

1 (NOTE: "CTRL-X“

MEANS PRESS THE "CONTROL"

KEY, RELEASE,

THEN PRESS

"X") X

I (SHIFT/X MEANS HOLD THE SHIFT KEY WHILE DEPRESSING THE "X")

3

8 X

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NURSE HDDE: CTRL-1

(Automatic after

system

reset)

Unmarked

prasigns:

:

SH/A

SH/Q

:

SH/E

N: SH/N

D: SH/D U:

SH/U

CH:

SH/C

ATTENTION:

SH/T

HYPHEN: SH/H

UNDERLINE:

SH/L

UNDERSTDDD:

SH/K

SEPARATION:

SH/S

BAUDDT NUDE: CTRL—2

CR: SHIFT/.

LF:

SHIFT/,

LTRS:

SHIFT/;

BELL: SHIFT/AS

RTTY ID:

"ID"

CH ID: CTRL-"ID"

(S)

ASCII

MDDE:

CR: LF:

BELL:

RTTV

ID;

CH

ID:

RANDOM CODE:

SLOW NUDE: NUDE l: MODE

PAUSE:

ALL MODES:

LOAD MESSAGES:

READ SERIAL NR:

PRESET SER. NR:

TRANSHIT TIME:

PRESET TIME:

REPEAT MODE:

PRELOAD

MESSAGE

MESSAGE MESSAGE

MODE:

"A":

"Bu: "C": "D":

CTRL—3

SHIFT/.

saxrr/,

SHIFT/AS

"X9.

CTRL-"ID"

CTRL—4

(standard

CTRL-5 (extended Place

any

letter other than

'

thru

"8" in

message

"A"

Place

letter "1"

through

"E" in

message

memory

"A"

Press SHIFT and hold

one

second;

to

release, press

SHIFT

again

spacing)

CTRL-At,

(Note:

send

message,

Message

then

ETRL

again

(for

message

"A”)

"A"

normally

will consist

of

your

call letters)

ETRL—Bt,

send

message,

then CTRL

again

(for

message

"B")

As above for "C" and

"D"

(Lamp

lights

two

characters

before full.

In

addition,

the buffer meter indicates

the

amount

of

message memory

storage

space

used)

(Message

"A"

must

be

programmed

be+ore

message "B",

any change

[of

length]

in

"A"

will affect

message

"B").

The same is true of "C" and

"D",

i.e.

program

"A"

first,

next,

"C" next and "D" last.

Any

later

change

of

length

in

a

preceding message

will

disrupt

the

following messages.

also

nsu

SHIFT/6 (This does not increment the

number) SHIFT/5

can be inserted

in

message

memories "A"

through

"D" where

each use will increment the number.

CTRL—b followed

by

four

digits

(most

significant

first).

Use

CTRL—I to

increment,

CTRL-D to

decrement

SHIFT/At

CTRL-7 followed

by

four

numbers (NSD first).

started at zero seconds as last number

Clock is

(LSD) is entered.

Preset

delay

interval in number oi seconds

by pressing

CTRL—-(dash)

{allowed

by

two

digits

(NSD first).

Messages

A!

through

D!

will

then

repeat automatically

until

the

SHIFT

key

is

pressed (during delay)

to release and reset

delay

to zero.

The overflow

lamp lights

during

the

delay

interval for

monitoring.

Type SHIFT/SPACE,

then CTRL to release

(Lamp warning

for overflow). Can also use SHIFT/SPACE

bar.

"Au!

nan‘

ucu’

nun‘

(6)

CR

MESSAGE

(CG CG DE

[message

A]);

type

SH/"C"!

CD

TEST

MSG (CG TEST DE

[message

AJ); type

SH/"D”t

“ID”

"ID"

key

QRZ

MESSAGE:

SH/"B"!

PRELUAD

BUFFER: SHIFT/SPACE

bar (CTRL to

release)

HOLD

BUFFER: SHIFT/SPACE

bar

(CTRL to release)

DELETE

LAST

KEY: "DELETE"

key

DELETE

LAST WORD:

"DELETE"

key

(from

sending

buffer

only)

MESSAGE

RESET:

RESET!

BUFFER

RESET:

RESET!

SET

SPEED:

Press ETRL—B

and

adjust

speed pot,

any key

releases

TUNE:

Press

CTRL~9,

SHIFT

to release

(gives

continuous

dots)

(3

Note:

Keys

followed

by

an "3" are

the NHITE

keys.)

E3F’EZ(3

IIF7 I C3¢§"T'I

CJBJSS

- - - - -

_ _ _ _ - - -

- - - - -

- - -

SPEED:

MORSE RANGE:

S TU BO

NPM

(Upper

end user

adjustable

higher

or lower)

BAUDDT:

45.45 baud

(60

upm).

8 unit

code: 1

START,

5

DATA,

2 STOP

ASCII: 110

baud. 11 unit

code: 1

START,

B

DATA,

2

STOP

SENDING

BUFFER:

256

keys

MESSAGE MEMORIES:

256

keys total,

soft

partitioned

into

Four sections

FIXED

MESSAGES:

CD CG

DE

(msg

"A")

EQ TEST DE

(msg

"A")

DE

(msg

"A")

DRZ

(msg

"A")

Incrementing

serial

number

24vhour

tine

MONITOR:

Internal

sidetone

generator

and

speaker,

volume and

pitch

adjustable

KEYBOARD:

54

key alphanumeric

plus space

bar, punctuation

and

prosigns

(AA,KN,BT,AR,AS,SK,KA

plus European

A,A,E’,D,U,CH

AND

N.

also

commercial

"ATTENTION", hyphen,

underline,

"UNDERSTDOD"

and

"SEPARATIDN“).

Gold inlaid

key

contacts

individually replaceable.

Sculptured

and tilted

two-shot molded

keycaps.

One character

produced

per key

depression.

Debounced

and

"TNU—KEY LOCKOUT”.

MANUAL

KEYINB:

with external

straight

key.

PADDLE KEYING:

with external

paddle key,

iambic

with dot and

dash memories.

(7)

55%:

=§;v

_.,,,.,d,,_H.W°,

5”/7’

=

/F7?

=

/477$/I/7'iaxV

INTEGRATED CIRCUIT CDHPLEHENT:

B035,

2732.

2114,

74LS75

(2),

74LS1b4,

lLD74(3), B044, 741-LS175,

7805

Euxth real-time clack

option

HC14518B (3)1

INPUTS:

RECEIVER AUDID...B Ohm!

PADDLE

KEY.......Single

or twin lever

(optically

xsolated)

MANUAL

KEY

....Telegraph key

(optically

isolated)

12

Vdc....

.....10 T0 14 Vdc 3 500 mA.

OUTPUTS:

KEYLINE... .

300V,

500mA max.

mercury relay

PTT......

....300V,

500mA

max.

mercury

relay

LDDP......

.....30OV,

l00mA

max.

(optically

isolated)

TTL TTY... .....TTL

level,

sink or source 5 MA

SPEAKER...

.....8 Ohms or

headphones

POWER REQUIREMENTS:

1l7Vac S0—60

HZ,10VA

OR 12Vdc 9 500 mA.

234Vac

50-50 HZ

by special

order

SIZE:

12" wide x B-1/2"

deep

x 4-1/2"

high.(30.4B

X 21.95 x

11.43

cm)

WEIGHT:

5.5 lbs.

(2.49kg)

FINISH:

Panel is

light grey,

bottom and

side

panels

are

textured black.

(lettering

in

white, yellow

and red)

PANEL

CUNTRDLSI

Speed, weight, pitch

and volume

controls;

tune/self—test

switch, power switch, system

reset

switch,

overflow warn-

ing lamp,

illuminated

speed

and bu+{er

status meters.

REAR

PANEL:

Jacks For

l2Vdc,

TTY

loop,

TTY

TTL level

output,

paddle

key,

manual

key,

transmitter

keyline,

transmitter

PTT,

receiver

audio,

and external

speaker

Dr

headphones.

117

Vac

receptacle

and ¥use.

(SPECIFICATIONS

SUBJECT TO CHANGE

WITHOUT NOTICE.)

(8)

C3F°EZF?é§1']iC3FJ-

- - - - -

--- - - - -

- - - - - - - - - -

Note:

Use shielded cable

{or all interconnections

between

the KB—4900

and other

units

including

the

keys.

!!X38XtllMPDRTANTtItltX

Always

connect

all the

transmitter

cables before

connecting

the

ac

line

to the KB~4900.

This

prevents problems

from

minute ac

leakage

from the

ac line

bypass capacitors

in the

KB—4900

Also,

make sure

the unit is

equipped

for the line

voltage you

are

using,

i.e.

either

117 DR 234 Vac.

Place

the "TUNE/DP/SELF—TEST"

switch

in

"SELF-TEST"

until

you

are

ready

to

go

on the

air. "SELF—TEST"

disables

the

keyline

and

PTT

relays.

CW KEYBOARD:

Connect

the

keyline

of

your

transmitter

to the

jack

marked "XMTR“ on

the rear of

the KB—4900. Connect

the PTT

line of

your

transmitter

to

the

jack

marked

"PTT" on the rear

of the

KB—4?00 (or

you

may

use

a

separate

hand or

foot switch

for PTT as

some

operators

prefer).

Connect

a

paddle key

and a manual

key

to the

respective

jacks

on the

rear

o4 the unit if

you plan

to use them.

Set

the SPEED control

at

midrange.

the WEIGHT

control at full

CCN,

the

pitch

and

volume controls at

midrange

{or

start-up

unless

you

have

already

set them where

you

like. Use the

HEIGHT control

very

sparingly

ii at

all. It is

normally

used

only

at

speeds

up

to about 20

Hpm

except

to

compensate

for slow

acting

transmitter

keying.

Use of

more than a

very

slight

weight

addition is

not a mark

of excellent

operating practice

and

Mr. Horse

didn’t intend it. But it

will

smooth—up

slow

speed

transmission

a

bit.

Connect a cable

from the 8 ohm audio

output

of

the receiver to the

jack

marked “RCVR” on the

rear of the

KB—4?O0 if

you

intend

to use

the "SPKR”

jack

of the

KB—49OO to listen

to mixed sidetone

and

receiver

audio. Note

that the RCVR and SPKR

jacks

are

simply

connected

in

parallel.

The KB—4900

comes on in the cw

mode. To

go

to the Cu mode from

either the Baudot

or ASCII

mode, thpe

CTRL-1. If in the

random

practice

modes, press

the

SYSTEM RESET switch.

Set

the desired

speed by

either

sending

characters

and

adjusting

as

you

listen or

type

CTRL-B

and

adjust

the SPEED

pot

until

the

desired

speed

is

read on the

speed

meter. Press the

SPACE

key

to

release

from this mode.

Preset

the time and serial number

if desired

by

referring

to the

GENERAL

DPERATIDN

section.

Similarly,

preload

the

message

memories

as described in

the GENERAL DPERATIDN

section.

(9)

Move the "TUNE/DP/SELF—TEST"

switch

to “UP”

and the transmitter

will

key

in the

CM mode.

Vou

may

tune

the

transmitter either

by

typing

CTRL-9

or

by

placing

the

"TUNE/OP/SELF-TEST"

switch in

"TUNE".

CTRL-9

will

give

you

a

string

o4

dots to avoid

overheating

the

transmitter

final

stage

during

protracted

tuning.

The

"TUNE" switch holds

down

both

the

keyline

and

the PTT line.

By

sending

either

from

the

keyboard

or the

paddle,

both

the

keyline

and

PTT

circuits will

be

activated,

the PTT line

will wait about

0.5 seconds

before

opening

for convenience.

The PTT line

is not activated

by

the

manual

key.

BAUDOT KEYBOARD:

Connect

a cable from

the

loop

circuit of

your

printer

and TU

(Terminal

Unit or

modulator/demodulator)

to

the

jack

marked

"LOOP" on the KB—4900.

This

jack

is isolated

From

the chassis

and the internal

circuitry

of the

KB—4900. It

will work

with either

polarity

o{ dc and

is rated to

key

up

to 300

Vdc at

l00 mA max.

Host amateur

loops

are

approximately

l9O

Vdc at 60 mA.

Make sure the

TU

loop

is

deactivated

during

hook-up,

otherwise

the 190 Vdc

will

appear

at the

exposed

end of

the

loop

plug

causing

a

potential

electrical

shock.

Also,

connect a cable

from the

PTT line and

keyline

of

your

transmitter

to the

respective

jacks

on the rear

of the KB-4900 (PTT

to

"PTT",

KEYLINE to

"XHTR”.

To

go

to the Baudot

mode, type

ETRL-2.

Now, typing

on the

keyboard

will

key

the

loop

circuit.

To

go

on the

air,

place

the “TUNE/DP/SELF~TEST"

switch in TUNE

before

starting

transmission.

This will close

both the

keyline

and PTT circuits

placing

your

transmitter in

the RTTY mode

where the

characters

are transmitted

by

FSK

(Frequency

Shift

Keying).

Type

just

as on

a normal

typewriter,

all

LTRS and FIGS shifts

are done

For

you

automatically

in addition

to all end~of-line

carriage

returns

and line feeds.

At the end

of

your

transmission,

return the

"TUNEIOPI

SELF—TEST"

to "UP".

Note that at the

beginning

and end

of

your

transmission

and at ten

minute intervals

during

the

transmission, you

are

required

to

send

your

call

letter identification.

Pressing

the

"ID"

key

will

send

the ID

in

RTTY, pressing

"SHIFT/ID“ will

send

your

CH ID

over the

loop

circuit.

This assumes

you

have loaded

your

call

letters into

message

"A" as described

in the GENERAL

OPERATION section.

If

you

experiment

with the code

speed,

you

will find a

speed

(around 13

wpn

for Baudot)

where the

printer

will

print

all O’s

during

the

ID.

I¥

you

want KDS

(Keyboard

Operated

Switch)

carrier

control,

connect

the

KB-4900 PTT

output

to control

your

transmitter

keyline

and/or

PTT

line,

a

0.5 second

delay

on

PTT

dropout

will

allow

momentary

pauses.

You

will need to "diddle"

with

the "LTRS"

key

to

prevent

dropout

otherwise.

(10)

TTL TTY

Output:

If

you

want to drive

your

external

RTTY

equipment

with a TTL

level instead of the current

loop, open

the unit

by removing

the four

screws on

the bottom and remove the

jumper

plug

from

P3 on

the

keyboard

PCB. This

puts

a

good

TTL level on the rear

jack

marked

"TTL TTY". This

signal

will

also

satisfactorily

drive

some EIA level

receivers. If

you

don’t remove the

jumper,

the

high

level

at the rear

jack

will be invalid

ASCII KEYBOARD:

Same

as above for Baudot

operation except

that

you

can send both

upper

and lower case

after

pressing

SHIFT/CTRL.

The unit comes

up

in the CAP

LUCK node where all

alphabetic

characters are transmitted

as

capital

letters. when not in the CAPS

LOCK

node,

use the

SHIFT

key

for

upper

case the same as on a

typewriter.

DUDE

PRACTICE:

You have

a choice of two

general

modes of random code

practice.

The first

is

true random where the

sequence

is

in

groups

of random

length

which

never

repeat exactly

the same

way.

Call

up

this mode

by placing

an "R" in

message

memory

"A" and

typing

CTRL—4 or

CTRL—5 (see below).

The second mode is PSUEDU RANDOM code

where the

groups

are

always

five

characters in

length

and will

repeat exactly every

time

they

are

played.

There are

eight

different lists called

by placing

a

number

from 1 to B in

message memory

"A"

and

typing

CTRL—4

or CTRL-5 (see below).

The

eight

code lists are available for

checking. They

run about 1500 characters

each.

To halt the code

practice

(for chow call

etc.), press

the SHIFT

key

for one second. To restart where

you

left

off, press

the SHIFT

key

for

one second

again. (Incidentally, halting

code

practice stops

the real~time

clock also.

Practice will

stop

at the end of each list. For the true random

mode,

practice

will

continue

indefinitely

until

you

hit the SYSTEM

ESET.

For

normally spaced practice,

use CTRL-4 to commence the

code,

for code

with extended

spacing

between

letters

(quasi-"Farnsworth Hethod"),

type

CTRL-5 to commence the

practice.

If

you

desire

only

the

alphabetic

characters

(no numbers or

punctuation),

load an "N" in

message

"A" after the "R" or number loaded for true

random

or

psuedo

random

practice.

The

speed

of

code

practice

is set

by

the "SPEED" control and

the

speed

meter indicates the

speed

of character

generation.

Note that

ypu’re

cheating

in the extended

practice

mode so the

wpm

indication

isn’t

correct

though

the

speed

of individual letters is correct.

Use SYSTEM RESET to exit from the

practice

nodes.

(11)

C3EEDJEEF?£§l_

CJF>EEF?£)‘r.IC3fQ- - - - - - _ - - - - - _ -

- - - -

Usually

the first

step

when

you begin operation

is to load at

least

message memory

"A" since

you

will

use it

constantly. Preloading messages

"B“,"C"

AND "D"

is at

your option.

For contest

use,

the

messages

to load

here will be obvious

except perhaps

for the serial number which

will

be

inserted

in some

fashion in

memories

"A“,“B"

UR "C" such as "UR

NR

--—-,

QSL?"

or

something equivalent.

The serial number will increment

by

one

each

time it is

used in

message

“A",“B“,”C"

DR

"

'.

You

may

also imbed

the

time in one o¥ the

messages

if

you

like. For

example,

you might

prepare

the

message

"TIHE HR l5 -—R——

GMT 12/24/30". For the other

messages,

you

can load in

sequences

like

"TNX FER RPT

—

UR SNN IN NEST

PDDUNK,

TX

“

NAME

HR IS TEX

~

TEX

—

RIG IS 50 AND SO RUNNING FIVE WATTS

TO A FUURTEEN

ELEMENT

YAGI

‘

SD

HW? ". You are limited

only

by your

imagination

and

the 256 characters

total

you

can load in the {our memories.

PRELDADINE

THE ESSABE

MEMORIES:

The

procedures

for

loading

each of the

message

memories

"A"

through

"D"

are

the same

except

that

you

must

proceed

From "A" to "B" to "C" to "D".

The reason For this is

that "B" starts at the end of

“A”,

"E" starts

at

the end of "B" and "D" at

the end of "C". This method is used to

get

maximum utilization

of the available

memory.

If

you change

"A","B"

or "C" (unless the

length stays

the

same), you

must redo

the

following

messages

also.

Note that

you may

have one

long message,

{our shorter

ones,

one short and

one

long

or

any

combination of one to four

messages

the total of

which

may

not exceed 255 characters

(keys).

Normally, message

"A" will consist

only

of

your

call letters.

To

prepare,

type

CTRL—Al (the white

"A“), type

your

call letters

and

then hit the

"CTRL"

key again

to

release from the load mode and end the

message.

You can include

any key

or shitt combination in

the

message including

the time or

incrementing

serial number. But not

including

the fixed

messages

(CD,CD

TEST.

QRZ AND THE ID’S)

Prepare

the

other

message

memories "B"

through

"D" the same

way using

white

keys B,C

AND D.

when

you

have

space

for

only

three

characters

(keys)

left

in the

TOTAL

memory,

the OVERFLDN

lamp

will

light

and

you

will

have to

stop

accordingly.

You

may

have to redo

message

"D" if

you’ve stopped

at an awkward

place.

Abort from the load

by terminating

with

a "CTRL"

key

stroke.

Note that the serial is called

by typing

SHIFT/6 and the time is called

by typing

SHIFT/At (white

key).

Put a

space

after

the serial and before

and after the time.

PRESETTING THE SERIAL NUMBER:

Type

ETRL-6 and

type

four number

digits starting

with the most

significant number,

for

example type

the 3 first if

presetting

the number 3456 or

type

the 0 first if

presetting

0135. or

type

three

0’s first if

presetting

0003 etc.

Normally,

you

will start

a

contest

by

presetting

0000.

Always type

in four numbers. The load terminates

on the fourth number. Vou can check

the

preset

number withour

in-

crementing by typing

SHIFT/b. This combination also loads

the serial

number

into

any

of the

message

memories.

(12)

when

the serial

number is

accessed via

a

message memory,

it increments

before

transmitting. i.e.,

if

you preset

to

0000,

the first number sent

via the

message

memory

will

be 1 (OOOX).

If

you

have a

problem

during

the

contest with the numbers

getting

out of

line,

you

can increment the

serial

by

typing

CTRL—l

or decrement

by typing

CTRL-D.

If the

serial number

gets

too far out of

line,

use the

preset

to

get

back on track. Note

that

the

decrement command takes

a

finite

part

of a second to

finish,

the OVERFLUU

lamp

will

iight

during

the decrement as a reminder.

SETTING THE TIME:

If

you

have the real-time clock

option, you

will want to set the time

after

you

have

turned on

the

unit. (The clock

only

runs when the unit

is

powered,

either

by

ac or 12 Vdc. Because this clock is not as

stable as a normal

timepiece,

it

may gain

or lose

time even if

left

powered.

To set the

clock, type

CTRL—7 and

type

in the time in 24 hour format

i.e. 7:00 PM is 19:00.

Type

the first three numbers

starting

with

the most

significant

("1” in the case of

17:00,

"O" in the case of

06:15,

etc.)

Type

the fourth number at the 0 seconds time and the

clock will

be

exactly

set. This means

you

will

normally

wait for the

next minute to come

up

before

hitting

the last

number,

Vou must

always

type

four numbers and the

preset

terminates

automatically

on the last

number.

To send the time over the

air, type

SHIFT/At(white ’'A"). You

may prefix

and suffix

a

space

as if it were a

single

letter

in the

text,

or a

more

elegant way

is

to imbed it in a

message

memory

with

the

PST,EDT,EHT

or

what have

you plus

the date. (TIME

HR

IS

12:45 PST

-

12/24/80)

You embed

the time

during

the

message

load

by simply typing

SHIFT/A! (white

“A").

USING THE FIXED

MESSAGES:

There are

four fixed

messages

in the KB-4900 which are

coupled

with

message memory

"A". These are:

1. CH CD DE

(message

"A") Note

that

message

"A" must be CALL

LETTERS

in these

messages.

This

message

is called

by typing

SHIFT/Ct (white "C")

2. CD TEST DE

(message

"A").

Type

SHIFT/D3

3. DE

(message

"A").

Type

"ID" (Use SHIFT/XD for CH ID

during

RTTY

operation.

4. DRZ

(message

"A")

Type

SHIFT/Bl (There is no "DE" in this

message

for

brevity.

(13)

PRESETTING

THE MESSAGE REPEAT DELAY:

You

can

repeat

the

message

memories

simply

by striking

the white

message

key repeatedly

or

you

can

use the

delay

mode for

delayed

repeats

of

from

1 to 99 seconds.

To load the

delay figure

in

seconds,

type

CTRL-- (dash)

and

then

type

two numbers

representing

the

delay

desired (in seconds).

Type

the most

significant

number First (the TENS

digit).

If the number

is less

than 10

you

must

type

the

leading

zero.

Now when one of

the four

message

memories

are called

up,

it will

repeat

continuously

at the interval

preset

until aborted

by hitting

the

SHIFT

key

while the

delay

is

underway.

The

DVERFLDN

lamp lights

during

the

delay period

as a convenience.

DELETE

FUNCTION:

Vou can delete

the last WORD

typed, assuming

it hasn’t started

transmission, by

hitting

the

"DELETE"

key.

SHIFT/RESETl(WHlTE KEY) has

the same effect

if

you

prefer.

Each

time

you

hit the "DELETE"

key,

the last word (back to

a

"space"

will be deleted.

If

you

are

loading

the

message

memories,

or

setting

the time or the

serial;

the

"DELETE"

key

will delete one

CHARACTER

per depression.

ABORT MESSAGE

MEMDRV DR BUFFER TRANSMISSION:

Hit the

white reset

key

and

the

message memory

and buffer

will be

reset. The

message

memory

is saved but buffer contents

are lost.

SVSTEH RESET

would do the same

thing

but the mode would default

to CM.

HDLD TRANSMISSION:

Transmission

may

be

temporarily

halted

by typing

SHIFT/SPACE. This allows

the

receiving

station to

break for a

repeat

etc. You can use the

paddle

during

the hold if

you

like. The transmission

will be continued when

you

hit the "CTRL"

key.

This feature can be

extremely

useful

in traffic

handling.

The "HOLD" is effective

in all modes

using

the

sending

buffer.

SYSTEH RESET:

when

you

turn on

your KB—4900,

the circuits are

automatically

reset

and the

unit comes

up

in the Horse

keyboard

mode. The time and serial

registers plus

the

message

memories will have

garbage

in them

as their

contents

,by design,

are not affected

by

a reset. When

power goes

off,

their contents are of course lost.

Normally,

the

only

time

you

have to

operate

the

systee

reset

(except

For exit trom the code

practice

modes)

is,

if for some

reason,

such as a

power

transient

or severe r.f.

interference,

the

processor

goes

bananas. If this

happens,

the

keyboard may

be

locked,

or

sending

the

wrong

keys

or there

may

be

a

string

of unwanted

characters

transmitting.

In

any event,

you

will Feel

you

have lost

control

of

things.

If

this

happens, hitting

the SYSTEH

RESET

will

make

every-

thing

right again.

The time and serial

may

be scrambled

depending

how

the

processor program

self destructed

during

the crash. The

program

is

permanently

locked

in the EPROH so no

permanent change

will

occur.

(14)

OPERATION UN +12 VDC:

Your

KBv48OO can be

operated

from

+10 TD +14 Vdc

batteries or

from

a mobile

power system.

You can

also use a

+12

Vdc

battery

continuously

connected for

battery backup

in case

of ac

power

failure. With the

battery

voltage

at or

below about

12

V

there should

be little drain

as

long

as the

unit is

powered

by

ac.

Connect the

battery

cable to the

KB-4900 before

applying power

to the

other end or

you may

get

a

spectacular

short if the

center

of

the RCA

plug

hits the

(grounded)

chassis! In

any event, place

an

inline 1

Ampere

fuse in the

battery

supply

line for

safety.

You can reduce

the

battery

current drain

by

half

by

removing

the

meter illumination

lamps.

CIRCUIT FUNCTIONS:

The KB—4900

consists of

an 8035

microprocessor.

a 2732 32K

bit EPRDH

for

program

storage

and a

2114 4K bit RAM for

sending

bufier and

message

memory storage.

An

B044 is used for the

keyer

section.

A 74LSlb4

is used for the

keyboard

"X" matrix

scan. Two 74LS75’s

are

used to latch the

EPRDM and RAM

addresses.

A

74LS175 serves

to latch

the lower four

hits of

port

2. Three lLD—74

dual

optical

isolators isolate

the

paddle

key,

manual

key

and RTTY

loop.

A 74LS3O

B-input

NAND

gate

is used to

detect a hexadecimal OFFH on

the

latched address

lines.

This is NORed with

the write

signal

from

the

processor

to

develop

a strobe for

writing

to an

external

parallel

ASCII

monitor.

If

you

have

the

real-time clock

option.

three

HC1451B dual BCD

counters

divide the

4OOkH2 ALE

frequency

to 0.4Hz. This

signal,

{ed to the

B035

port

17, provides

the clock

reference.

CALIBRATION:

Normally, your

KE—49OO

will not need

calibration

over the life of

the

unit

however

you may

touch

up

the

settings

if

you

desire.

1.

Haximum

speed

limit:

This

parameter

is set

by

adjusting

a

trimmer

labled "R1" and

located on

the small PCB

located

on the

rear

panel

of the unit.

It is the

only

trimmer on

the

board and is

accessable

by

simply

removing

the

four screws

holding

the

bottom

wrap-around.

You can

adjust

the maximum

speed

(when

the

speed pot

is

full clockwise)

by

rotating

the

trimmer

until

the

speed

meter reads

your

desired

maximum.

2.

Speed

meter

calibration:

A trimmer

on the

keyboard

PCB controls the

calibration o!

the

metering

circuit.

Connect an

oscilloscope

or

pulse

measuring

counter to

14 of the 8044

IC. Set the

speed

pot

to

give

a

reading

of 48

ms. for

cycle

length

when

the dot

key

(or

CTRL—8) is

depressed

(dot is 24

ms., space

is 24

ms.). Then

adjust

the

trimmer

marked “s” on

the

keyboard

PCB. This trimmer

is

accessible from

the

top

or

bottom of the board.

hen the

speed

meter

upm,

the

adjustment

is correct.

(You will NOT HEAR

dots

during

this test

if

you

use CTRL-E.

They

are muted.)

(15)

3.

Buffer meter calibration: Another trimmer

on the

keyboard

PCB controls

the buffer meter

calibration. Press SHIFT/SPACE(bar)

to

place

the

unit

in a

preload position.

Then

type

keys

at random

until the buffer

fills and the DVERFLDN NARNING

lamp

lights.

Hit three more

keys

to

completely

fill the

buffer,

then

adjust

the trimmer marked

"b"

on

the

keyboard

PCB until

the buffer meter

indicates "I00". Press

the SYSTEM RESET to reset the

unit. Note that this

trimmer is also

accessible from the

top

or bottom of

the PCB.

I bl CIKXESEE EJF7 I I F7F='I CZLJL_1'\’-

- - - - - - - - _ - - _ _

Field trouble

shooting

is best

accomplished by

substitution of

IC‘s based on an educated

guess

of

possibility.

Or

just

blind

substitution if

no

localization can be made. The

only component

not available in the field is the EPRDH which

must be ordered from

the

factory.

The B044

may

also be

obtained from the

Factory.

D4

course,

any component may

be ordered from us if

desired.

If

you

can’t locate the

problem,

call or

write us for

help.

we'll

suggest

the

best

way

to

proceed, possibly

requiring

the return of the

unit.

L. IP4 I'TEEI) UJ€§F?F?£§hJ1'\(_ - -

- - - - - - _ -

- - - - - - - - -

He will

repair any

defect caused

by components

or

workmanship

without

charge

for labor or materials for a

period

of 90

days

after

you

receive

the unit. You will be

responsible

for

shipping

both

ways

from our

factory.

After 90

days,

we can

quote

the estimated

repair

cost after

examining

the unit

according

to

prevailing wage

and

material costs.

Although complicated

in

Function,

the KB—4900 is

quite

simple

in

execution so

repairs

should not

be too difficult. In

addition,

all lC’s are

socketed for

ease of

servicing.

The one

event which ruins a lot

of amateur

equipment

is the

electrical storm.

This sometimes turns

part

of the

circuitry

into soot

and

invariably

burns out

every

semiconductor. If not too

severe,

we can

sometimes

repair

the

unit

at an

acceptable

cost. In

any event,

see

if

your

homeowner’s insurance

covers such

things

so

you

can

easier

decide what

you

can bear. The best

insurance

against

electrical

damage

is to

disconnect the ac

power

from the

station

completely

(Pull the

main

plug,

don’t

depend

on

the switch) and

ground

and

disconnect

your

antennae from

your

equipment.

F’F?(3(3F?¢§r4

C:F1£\PJC5EEE3 FNPJI)

F?EE\J I 53 I

CJPJES - - - - - -

The

program

in

your

KB-4900 is

contained in an EPRGH.

This device can

be

erased

with

ultraeviolet

light

and

reprogrammed quite

easily.

If

we

make

product updates

of the

program,

we will

correspond

with

you

to ascertain

if

you

desire

the

update.

If the

update

is a

correction o6 a

problem,

the

only

cost would

normally

be a

small

mailing charge.

If

the

update

is

a

signiicant

improvement,

there

may

be some

reasonable

charge

depending

on the

nature of the

change.

You

may change

the (socketed)

EPRDH

yourself

or if

you

don’t

feel

up

to

it, you

can

always

have

us do it. The

only

difficulty

is

inserting

the

device into the

24

socket without

mashing

the

pins.

Otherwise,

it’s a five

minute

job.

CURTIS ELECTRD

DEVICES, lnc.,

Box

4090,

Mountain

View,

CA

94040

Tele: 415 494

7223 TNX: 910 373 2017

Cable:

CURTIS,

PALD

ALTO,

CA

Shipping

address: 4140

Transport

Ave.,

Palo

Alto,

California

94303

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