Palomar R-X review

CQ

Reviews:

The

R

P alomar Engineers is

Palomar

-X

currently

Noise

BY HUGH R.

marketing

an R

-X

PAUL'

of t

Engineers

Bridge

, W6POK

he

unkno

wn

ca

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fo

un

d at d i

ff

er

ent

Noise Bridge

be

an
Those

of

or

ing and adjusting in

ac
pro
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in

accessory

an R-X

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co

ross the band?

bab

dj

ust the len

every

of

you

noise

many

nstruc

ly were d

for

ham

who

times have you

ted a d

$39.95. This is a dev

shack

item

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end

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worthy
is

definitely

notfamiliar

reading

installed

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then spen t

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om the R and X

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adin

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wave length

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tor

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Engine

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s R-X Noise

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by the noise genera

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this tells us

itt

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on

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te

page 7

half

own, the r

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read

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When

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Macatester Drive, Walnut, CA 9

bridge

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Rand

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The

Palomar

Engine

er

s R-X noise

Ap

ril,

J977

br

•

idge

CO

.

•

37

Zero Bias (fro m page

5)

Palomar Noise Bridge (from

pag

e 33)

timer
Sometimes we take

phrase

Rather than appear
block,
do

material.
some
active bunch

aware

will

we

felt

more to

After

of

the busiest people in the

of

what

topicsare covered each

for

granted

be meaningful

or

in fact

that

promote

all,

of

the

as

tit

a

better

I said

amateurs anywhere. We also have

to

all those

to

les

of

lastmon

understanding

the best (and I mean best) group

ing

today

on amateur radio. We

month

that

a ca

tch

who

word

see

or

be an exclusionary

the columns should

of

the

th,

wor

of

columnis

want

we cater

ld, the

ts writ-

mo

re

of

most

you

it.

to

only

fuse employed is in the cathode

.

8873 to prevent over

amplifier
warmup of

tube. A time delay circuit insures

the

being applied .

The amplifier input

1500 ohm, 2

watt
a 100 ohm, 30 watt resistance. This resistan
parallel with the 8873's cathode

causes the e

xc

load on all bands . This resistive netw

sipates a

portion

driving

8873 filament

circuit

resistors in parallel, which form

iter to

of any

look

exce

into the desired 50 oh

circuit

of

th

and thus damaging the

prope

prior

c

to

plate voltag

on

sist s of fifteen

ce,in

circuit

impedance,

ork

also

di

s

ss driving power. Th

to

take a second

first

to

look

One

at

what's

of

the things we have in the

increase the

ducts and products

month

Shack

for

SeT

instance

-11

a review coming

look

and many

of

you

to

take

being offered.

number

of

Bill

of

Reviews

interest

DeWitt

of

to

delves

works

amateur pro-

amateurs.

into

for '77 is

the Radio

stereo cassette tape-deck and we have

up

by

Adrian

Weiss on the

Heathkit

HW-8 GRP c.w. transceiver. Hugh Paul is hard

work

several months.

generating a

Anything

number

of

you'd

Reviews

like

to

for

see?

the

Let me

that

Th

is

at

next

75 to 90

the

amplifier

The output

with

additional fixed padding capaci

tuning and

watt

o

utput

of most transceiver s

to full output on all band

circuit

of

the amplifier is a pl-netw

to

loading

capacitors on the 80 mete

will

driv

s.

or

rs across th

band. Ferrite beads are used in the plate lead fa

parasitic
grid

p

ower

and plate

Power

570 watts, d

inputfor

suppression.

curr

ent, high voltage and relativ

Metering

output.

output

epending

on c.w. ranged from 630 watts t

on the band

s.s.b. is 1200 watts PEP on a

functions manito

in

use. Rated

co

ntinuou

know

and

I'll

try

to

arrange

it.

We have a number of great articles in the

for
busier than

ial

that
been

same

tion

'77

for

and

co

my

so

my

why

second year

first.

We are

not

take some t ime and send in

article. Give us all a chance

doing

la

tely

and perhaps get paid

time.

April

of

is also

Dayton

the

to

month

most

for

of

us is enough

as

Editor

looking

to

Dayton.

for

see

imagination and produce a roaring fire.

initia

found

about

me tell

worth
20th

ted

the

or

newcomer,

time

, f

Daytonfrom

you

the

Dayton

that

effo

rt

Hamven

for

or

those

people

it

is amateur radio personified and

to

get there. This year marks

tion

the old

who

just

who

and

timer

settle

have been there let

for

three solid days

works

looks even

new mater -

what

forit

Just

to

For

kindle

you've

at

the

the

who

for

hearing

the

men-

the
un-

never

their

duty
tinuou s as

not exceed 30 seconds.
of 400 watts f

transmit

ratings are adequate
mind the fa
amplifier

be e

may

The

is

cycle. The c.w.

long

time

must

ct

will prevent damage should these ratings

xc

eeded. Other

not

fair

as well if

slightly

justified

by the use

duty

cycle is rated as

as maximum key down time

At

the reduced input level

or

that

higher

RTTY and

not

the

exceed 10 minute s. Thes

for

most operat

protecti

amplifie

their

cost of the
of

the more expen sive Eimac

55

TV the maximum

or

s. Keep in

on

rs in

cir

this

cuit

power class

ratings are exceeded .

58-230

ca

n

doe

s in the

($369.95)

8873. It's other design features are a bonus.

The

tortion

58-230

pr

oducts

is a clean

are

better

amplifier

than a - 30

. Third

orderdi

db

down

s-

from the rated output , provided the driving trans-

mitter
order

is at least that

products

. A

dirty

good

driver

with regard to

signal is

going

third

to give

and nights

There are programs

of

e

xhibits,

flea market

sorts

of

marvelous things guaranteed

interest and wallet. Bring an

home all

c o

will

ward to meeting many

the

you

fo

I'

are inundated

fo

r every interest, an arena

with

amateur radio.

rums, technical sessions and the best

ve ever

seen

wi

th

acres and acres

to

capture

extra

suitcase

goodies.

have

their

boo

th

of

set

up

and I

you and getting the

chance to exchange some ideas. Dick Ross,

will

be

out

the re

to

help

with

the

booth

of

your

to

carry

look

for

K2MGA

and

we'll

full

all

you a

amplifier

dirty

can be

output

amps or 240 v.a.c., 50

The Heathkit

plete

detail s f

56·230

or

can be found in most g
for

the amateur.

-

The

bridge

can also be used
resonant frequencies and impedan ce of tuned cir
cuits
to the

or

to assist you in cutting

proper

length.

signal. Primary p

either

using

120 v.a.c., 5

/60

Hz at 7 amps . •

(from page 37)

the

ood

brid

antenna books

owerfor

0/

60 Hz at 14

ge

in this manne

writt

to

tr

determine the

ansmission line

th

en

probably
the
of

70

CO columnists

fun

• co • April ,

so

be

why

jo

ined f

not

ro

m

time

who

show up each year.

come on o

1977

ut

to

time

by

ma

It's

and

join

us.

73, Alan, K2E EK

ny

a

of

lot

The

bridge

is a

ccurate

enough f

uses up to 100 MHz and with a
will bec ome
you ever g

proficient

ot

along with out it. •

in its use and w

or

little

most amateu

pract

onder

ice

you

how