Knight TR-106 User manual

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OPERATOR'S MANUAL
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TR-106 6 METER
~ TRANSCEIVER

SPECIFICATIONS
RECEIVER SECTION
TABLE OF CONTENTS Audio Output: 5 watts or more
Intermediate Frequencies: Ist LF -tunable from 15.6 to 17.6 me
' 2nd I.F.-——1650 ke
Page IF. Rejection 50 db or better for Est LIF,
eee peees 9 70 db ov better for 2ud LF.
PIPE TIC AIIQINS tesa io hea ha ap Be eS Ae) A nae hel hie sar Image Rejection: 58 db or better
anlich Poni iane + we diecttiad sul et itdx darth cnete dusalet tal 9 Input Impedance: 50 ohms nominal
Selectivity: 6 db down at & ke
: : : SN
Step
by
Step
Operating
Instructions.
.....---
5-2...
e
serene
es
f
Sensitivity:
0.5
microvolt
for
LOdb
47
ratio
Operating? Hints: 2s. o2.04¢8o6d eee ae hee on tay eee eee eS 5
TRANSMITTER SECTION
TOM eee Bi eke ee SOA a peel neh cs ba ed wows 6
Propagation
,
Frequency
Control:
Fundamental
cut
8
me
crystals
Berek or VEO at 8.8338 to 8.666 me
P Frequency Range: 50 to 52 me
Antounas 2.0.0 cc ccc cece cece cet veveeeyecus BS Desince cos een 7 Modulation: Amplitude modulated plate aud screen,
limited to approximately + 950%
Mabie Tistillatione Cousideratia tse oon orcas oe eee ws 8 Output Impedance: 30 to 90 ohms nominal (with VSWR of 3:1
or less)
Television Interference ... 0... 0c. e ee ccc cece c ee tne ee beeen eens 11 RF Power: Input: 15 watts nominal
Maintenance POWER SUPPLY (solid state):
Ay 14 Power Requirements: 110-130 volts, 60 cvele AC— 90 watts re-
Helinme@nt sect eee ko itis She nie ee ete Seg I hd ecived LO walle transmit
* ; ; 12-15 volts DC) 6.8 amps receive /8.1 amps
Frowble-shoOOtng@ s.cs0.2 eas eee eee ne Pee ha ae Pe Be 16 traismit
+ ot . Rectifier: Full-wave voltage doubler with silicon di-
Circuit
Description
..
6.6.6
666
eee
ee
17
odes
Warranty ©... 6.66. ee ete eee eee 24d
TUBE COMPLEMENT:
Schematic
Diagram
©...
6.6.
eee
Insert
Receiver:
6DS---Nuvistor,
RF
amplifier
61 AS-— Est mixer/oseillator
Parts: List v.68) 64 28842 Sg pn hoi RA ee eh a Ge a eee ee eo Insert GIAS- -2nd mixer/oscillator
G6BZ6- -Ist LE. amplifier
GBZG6- 2nd 1... amplifier
GALD5S- -Detector/ANEL diode
1ZAX7- -Audio/mic preamp
GLGGC Audio output /modulator
Transmitter: 12D K6- --Oscillator/tripler
IZAQH Buller/doubler
2626 Final power amplifier
Size: 5b ox ble’ x 11”
2

CONTROL FUNCTIONS
This short description of the function of cach control available from the
front and rear of vour transceiver, supplies background information for
proper operation of vour transceiver. For step-by-step operating instrue-
tions, see the next seetion of this mantel.
Tuning Dial- tunes the receiver section to the desired frequeney.
Meter-- -in receiving function, it indicates the relative strength of the in-
coming signal. The upper seale is calibrated tn “S"” units from £ to 9 and up
to 30 db over 8-9. (S-9 50 vv input signal).
fn the transmit funetion, it acts as a relative power output indicator. It is
used during loading and adjustment of the transmitter.
Use the meter for precise tuniug of the receiver; adjust the Tuning Dial
for maximum indication on the meter.
‘
The meter is also used as the indicating device for the “spotting”? funetion.
TRANSMIT Indicator lights when the transceiver is in the transmit fune-
tion.
LOAD-- -matches the output of the transmitter to the antenua. It can be
used to match antenna impedances of 30 to 90 ohms, providing the VSWR
is 3:b or less.
PLATE is used to resonate the plate circuit of the transmitter final ampli-
fier at the operating frequeney.
PHONES for listening to the receiver with headphones. Use low-impedance
phones 4 to 16 ohms. The speaker is muted when a phone plug is inserted
into this jack. Also, a remote speaker can be connected to this jack. If vou
use high impedance phones, they must be shunted by an & ohm 2 watt
resistor,
TRANSMIT-RECEIVE- activates the transmitter or the reeeiver funetion.
This switch may be used in conjunction with a microphone which does not
have a push-to-talk button. When left in RECEIVES, a microphone push-
to-talk button will operate as the transmit /receive switch. This switch is
also used when tuning and adjusting the transmitter,
NOTE: The microphone provided with this transceiver has a shorting cou-
nection across the microphone clement when the push-to-talk button is in
the receive position (button out). Thus, you ean make transmitter adjust-
ments
without
fear
of
audio
pick-up
from
the
microphone,
by
operating
the front panel TRANSMIT-RECILVIs switch.
MULT resonates the plate cirenit of the transmitter oseillatoer/tripler
stage to the operating frequeney. Its adjustment determines the grid drive
to the final amplifier.
CRYSTAL sclects the transmitter frequeney-deterntining erystal or VEO
input. Positions 1, 2 and 3 correspond to the numbered crystal sockets to
the left of this switeh.
SPOT-OFF- provides a transmitting frequency spotting fonction. When set
to SPOT, the Tuning Dial can be set to the exact transmitter frequency
by observing the Meter indication. The SPOT funetion operates for both
erystal controlled and VEO operation. Thus, vou can set the reeeiver and
the transmitter to the exact same frequeney,
RF GAIN varies the output level of the RE stage. This control is in the
rathode circuit of the 2ud Mixer, therefore it varies the output of this
stage.
POWER-OFF-.- turus power on and off,
AF GAIN—vaties the level of the audio signal for the reeeive funetion.
This control is in the grid cireuit of the audio pre-amp,
The microphone is connected to the jack to the left of the PILONES jack.
ANT connector on the rear panel. Attach the coaxial cable from your an-
tenna system to this counector,
The 12-pin power connector is for the input power; either 120 volts AC or
12 volts DC can be used for power. Two power cords are available- one for
120 volts and one for 12 volts.
VFO PWR Power is available from this conuector for an external VEO;
30 ma at 200 VDC and 0.8 amp at 12.6 VAC,
S MTR is used to set the meter on the front panel to zero, when no signal
or noise is being received,
VFO INPUT connect the output from a VIFO to this jaek.
ANL-ON (automatic noise limiter) -when in the ON position, it switches
an automatic noise limiting circuit into the receiver. This reduces pulse-
type
Noise
such
as
automobile
ignition,
sharp
bursts
of
static,
ete.
When
you turn this switch ON, the volume of the receiver may drop slightly; this
is normal, and has no effeet on the sensitivity of the receiver.
3

STEP
BY
STEP
OPERATING
INSTRUCTIONS
You
must
have
a
current
Amateur
Radio
license
to
operate
this
transceiver
on
the
air.
A
Novice
Class
Liecuse
does
not
permit
use
of
this
transceiver.
Before
you
actually
start
to
operate
your
trausceiver,
we
suggest
that
vou
turn
to
the
OPERATION
section
of
your
manual.
A
number
of
important
points
are
discussed
and
specifie
information
is
given
about
antennas,
mo-
bile
installations
and
general
operating
considerations.
[|
|
Conneet
the
microphone
to
the
microphone
connector
on
the
front
panel,
|
|
Connect
an
antenna
to
the
ANT
connector
on
the
rear
of
the
trans-
ceiver,
[|
|
Conneet
the
proper
power
cord
to
the
power
connector
on
the
rear
of
the
chassis
and
to
the
power
source,
CAUTION:
NEVER
TOUCIE
ANY
OF
TILE
WIRING
OR
REMOVE
ANY
TUBES
WIHILE
TH
UNIT
IS
ON.
BE
ESPECIALLY:
CARMFUL
TO
AVOID
CONTACT
WITH
THE
PLATIC
CLIP
OF
THI
2426
TUBE,
VOLTAGES
USED
IN
TIS
UNIT
ARE
DANGEROUS.
TO RECEIVE
Set
TRANSMIT/RECEIVE
switch
to
RECEIVE
and
SPOT
to
OFF.
Turn
the
POWER
switch
on.
Turn
RE
GAIN
maximum
clockwise.
Adjust
AF
GAIN
for
desired
level
of
sound.
Adjust
the
tuning
dial
to
the
desired
frequeney,
To
set
the
S
meter
to
zero,
disconnect.
the
antenna
and
adjust
the
S
MTR
control
on
the
rear
of
the
chassis
so
the
meter
needle
rests
at
0.
if
excess
static
type
noise
is
present
in
the
signal,
set
the
ANL
switch
on
the
rear
of
the
chassis
to
ON,
NOPE:
Any
noise
that
you
may
hear
in
the
transceiver
is
almost
totally
from
external
sources,
The
receiver
itself
is
exceptionally
quiet.
Remem-
ber,
steady,
high
noise
levels
caunot
be
eliminated
by
the
ANI
circuit.
When
the
level
of
the
noise
approaches
the
level
of
an
incoming
signal.
switching
in
the
ANI,
will
reduce
the
level
of
the
signal,
along
with
the
noise.
Noise
problems
ean
not
be
solved
internally
(in
the
transceiver)
;
they
must
be
solved
at
the
source
of
the
noise.
This
brief
discussion
will
be
especially
helpful
if
you
use
the
transceiver
in
a
mobile
installation.
See
MOBILE
INSTALLATION
CONSIDERA-
TIONS.
TO TRANSMIT
Caution:
Never
operate
the
transmitter
without
an
antenna
or
dummy
load
connected
to
the
ANT
jack.
Also,
never
operate
without
a
VFO
or
a
erystal.
irst,
determine
if
you
are
going
to
use
a
VICO
or
crystals
for
determining
the
transmitter
frequency.
For
VEO
operation,
use
a
VEO
capable
of
at
least
15
volts
RMS
output,
which
covers
the
range
8.388
to
8.666
me.
Crys-
tals
must
be
of
the
fundamentalcut
type
in
the
range
of
8.8338
to
8.666
me.
For
MARS,
use
a
standard
MARS
crystal
(8.33
me).
Note
that
the
multiplication
factor
for
erystal
or
VFO
frequency
is
6.
Thus,
if
you
want
to
find
the
crystal
frequeney
that
will
place
you
on
a
specific
frequency
in
the
6
meter
band,
divide
bv
6.
{|
Plug
your
erystal
into
one
of
the
crystal
sockets
or
plug
the
output
from
your
VFO
inte
the
VFO
INPUT
connector
on
the
rear
of
the
chassis.
Set
the
CRYSTAL
VIO
switeh
to
the
correct
position
(VEO
or
f,2
or
8
depending
on
the
position
of
the
crystal).
CAUTION:
When
vou
use
the
matching
VFO
with
this
transceiver,
be
sure
the
VFO
power
plug
is
properly
connected
to
the
socket
on
the
transceiver
—
The
serew-head
positioned
toward
the
12-pin
power
connector.
||
With
POWER
on
aud
antenna
connected
to
the
ANT
connector
on
the
rear
of
the
chassis,
set
TRANSMIT/RECEIVE.
switeh
to
TRANSMIT.
1}
Adjust
MULT.
PLATIC
and
LOAD
for
maximum
meter
reading.

The transmitter is now adjusted for this operating frequeney, A change
in operating frequeney of up to £50 ke (total, 800 ke) will not require re-
tuning the transmitter,
To modulate, press the microphone button aud speak into the microphone.
You will find that a setting of the Mie Gain control (serew-driver adjust-
ment on the right side of the chassis) at mid-range will result in adequate
modtuation.
Any type of high impedance microphone may be used with this trauseeiver,
A carbon mie can not be used.
If you are using a desk-type microphone without a press-to-talk switeh,
use the TRANSMIT-RECIEIVE switch on the transceiver. If you use the
microphone that comes with the transceiver, or any mierophone that has a
press-to-talk button, leave the TRANSMIT-RECEIVIS switeh in’ the RE-
ChIVIG position and use the mic button for transmitting,
The microphone that comes with the transceiver has a shorting connec-
tion across the microphone element. Thus, no sounds are pieked wp by
the microphone when the TRANSMIT-RECEIVEE switch is in the TRANS-
MIT position. ‘This permits tuning operations to be made without extra-
neous sounds being transmitted.
Fov precise setting of the Mic Gain control, adjust it for the best sound by
sighal
report.
or
by
monitoring
the
modulation
pattern
on
an
oscilloseope.
Since the modulation circuit has been deliberately designed to limit modu-
lation to ' 95%. a high setting of the Mie Gain control will result in dis-
tortion of the audio, rather than over-modulation,
NOTE:
If
you
want
to
tune
the
receiver
to
the
exaet
frequency
of
the
trans-
mitter,
turn
Ri
GAIN
maximum
counterclockwise
to
CAL
and
turn
SPOT
on.
Adjust
the
tuning
dial
for
maximum
meter
reading.
The
receiver
is
now
tuned
to
the
same
frequeney
as
the
transmitter.
Return
SPOT
to
OFF
and
readjust
Rie
GAIN
as
required.
When
you
use
the
spot
feature,
you
may
notice
two
points
on
the
tuning:
dial
where
a
meter
reading
is
obtained,
The
lower
frequency
point
is
the
correet
once,
These
two
points
will
be
about
E
me
apart.
OPERATING HINTS
Here are a few points that should be kept in mind as you operate vour
transceiver,
Remember to identify your transmissions at least every 10 minutes. Some-
times it is easy to forget, when vou beeome engrossed in a “rag chewing”
session. Identify by station ell at least onee in cach 10 minutes.
Ik. C. regulations prohibit the use of amplitude modulated transmissions
from 50.000 to 50.100 me; this segment of the band is for c.w. only. Keep
this in mind, especially when working DX to other countries. Some coun-
tries, Canada for example, permit use of this segment of the band for a.m.
operation. So, just a word of caution, do not call back on their frequency if
they are below 50.100 me.
If you have not been active on 6 meters, or have just moved into a new
avea, before vou start extensive activity, check local nets and calling fre-
quencies. Avoid using the same frequencies that nets utilize. Keep in mind
tht operation in the VITF bands is considerably different from the lower
bands. Activity is concentrated in local areas and on specific frequencies.
Since so much activity on the VITF bands is associated with nets, here are
some handy conversion figures to keep in mind when handling traffic and
other functions requiring the recording of Greenwich Mean Time.
To obtain GMT, add | hours to Atlantic Standard Time, 5 hours to Kast-
ern Standard Time, 6 hours to Central Standard Time, 7 hours to Moun-
tain Standard Time and 8 hours to Pacific Standard Time,
For operation under the Military Affiliate Radio Service, contaet the net
control station of the local net. You will be supplied with the necessary
information and forms for application. Do not operate on the MARS chan-
nel until you have received proper authority. You must use a erystal for the
MARS channel; do not use VFO control,
One last thing support and adhere to The Amateur’s Code. Vhe Ama-
teur is Gentlemanly 2... Loval... Progressive... Friendly... Balaneed
Patriotic.

PROPAGATION
The
VEF
bands
seem
to
be
the
bands
of
the
future.
Activity
and
interest
in
the
higher
frequency
bands
is
swiftly
increasing.
Proposed
changes
in
regu-
lations,
crowded
conditions
on
the
lower
bands
and
a
renewed
interest
in
experimentation,
have
all
contributed
to
this.
Most
“hams”
concentrate
on
DPX
communications.
The
greater
the
distance,
the
more
enjoyable
the
contact.
Normal
ground-wave
communications
on
6
meters,
with
a
transceiver
of
this
power
level
will
be
from
25
to
50
miles.
This
range
will
vary
with
the
type
and
height
of
the
antenna
used,
Ranges
over
100
miles
are
possible
with
a
multi-element
array.
Mobile
stations
are
limited
to
shorter
distances,
due
to
the
antennas
involved,
USUAL
PATH
deunie
ete
With
higher
power
and
elaborate
antenna
systems,
the
normal
radio
hori-
zon
can
be
extended
to
about
200
miles.
This
is
greater
than
the
“line-of-
sight”
distance,
because
the
carth’s
atmosphere
bends
the
radio
waves
slightly.
Thus,
the
radio
wave
follows
the
curve
of
the
earth
for
a
distance
greater
than
the
line-of-sight
path,
°
Distances
greater
than
the
radio
horizon
are
common.
This
is
due
to
“skip”.
.
SPORATIC
ie
‘
:
ae
pas
:
:
,
1
clove
AURORA
Skip
varies
with
many
conditions.
The
drawing
provided
will
serve
to
illus-
QOS,
trate
this
point.
N
as
rt
VAS
gf
if i)
1
Tropospheric
propagation
extends
up
to
approximately
800
miles.
Many
factors
enter
into
this
type
of
propagation,
but
basically,
the
radio
wave
is
bent
by
the
troposphere
and
is
returned
to
the
earth
at
some
point
beyond
the
normal
radio
horizon.
FARTHER
Sporatic
skip
communieations
result
from
bounce
off
of
ionized
lavers
of
dust
or
“ion
clouds”
at
altitudes
of
50
to
70
miles.
This
ean
produce
com-
2000-2800
MILES
munication
ranges
of
up
to
1500
miles.
Double
skip
can
greatly
increase
0
eT
ental
en
lb
on
MULTIPLE
this
distance.
Propagation
from
“aurora
borealis”
curtains
oc
casionally
occurs
ina
similar
manner,
This
is
usually
limited
to
northern
latitudes.
Radio
reflection
from
the
F
2
layer
is
the
most
common
method
of
DX
com-
munication
in
the
VIF
bands.
Distances
of
over
2000
miles
are
quite
hormal,
Propagation
in
the
VIIF
bands
depends
greatly
on
the
sub-spot
activity.
Amateur
Radio
periodicals
usually
report
current
conditions
and
will
give
you
information
to
help
prediet
opportunities
for
DX,
Local
nets
will
prob-
ably
have
up-to-date
information
on
propagation
conditions.
The
entire
field
of
propagation
predietion
is
still
experimental
and
much
study
is
being
done
by
industry,
as
well
as
“hams”.
For
reterenee
informa-
tion,
we
reeommend
The
Radio
Amateur’s
Handbook,
Wditors
and
Engineers
ame
Handbook
and
your
local
technical
library,

OPERATION
ANTENNA SYSTEM
The antenba system includes the transmission line, and it is very impor-
tant that vou use the correct type of transmission line. The transmission
line should be of the coaxial type and should have an impedance equal to
the antenna impedance,
Since your trauseeiver is designed to operate most efliciently into a 30 to
90 ohm load, it is best to use a type of coaxial cable with an impedance of
50 to 52 ohms. We suggest type RG-58/U for short leugths and RG-8/U
for long lengths.
Generally speaking, you should keep the length of the transmission line to
a mimnmum. Remember that line losses increase with frequeney. li the
VEL bands, loss can be considerable. Use foam-insulation coax for best
results.
If the transmission line must be long, keep it to exact multiples of a half-
rave length, that is, multiples of 9.8 feet. This will assure a proper im-
pedance match and thus maximum transfer of power from the transmitter
to the radiating antenna.
The above discussion is as important for reception as it is for transmis-
sion, If a mismatch exists between the antenna andthe receiver, the ex-
cellent sensitivity and sigual to noise ratio of the receiver will be defeated.
FIXED STATION ANTENNAS
The most popular fixed station antenna is a directional array. It may be a
relatively simple beam, or a complex collinear system.
Beam antennas provide maximum gain, maximum directivity and usually
are horizontally polarized. The directivity can be a disadvantage for net
operation, but the other advantages usually out-weigh this problem. Since
a beam antenna is directional, it: greatly reduces noise and interference
from all other direetions. This can be a decided advantage in the VIF
bands where man-made noise is a problem.
Polarization
is
an
important
consideration.
On
the
6
meter
band,
horizontal
polarization
is
more
popular
than
vertical,
Cheek
with
local
hams
for
in-
formation
on
local
preference,
since
it
is
important
to
keep
the
same
polari-
zation
over
line-of-sight
aud
ground
wave
communications.
Skip
conditions
usually distort the polarization; thus, for DX operation in this band, polari-
zation is not as great a consideration. Also, keep in mind that most man-
made
noise
is
vertically
polarized.
Vertical
polarization
has
two
advantages,
omni-directionality
(for
net
operation)
and
TVI
is
less
of
a
problem
(since
TV antennas are horizontally polarized).
A
simple
dipole
antenna
is
very
suitable
for
a
temporary
antenna
system,
Keep
in
mind
that
transmission
and
reception
is
broadside
to
its
length.
The
illustration
shows
how
to
construct
a
simple
dipole.
“
oa a fs 2 same JQ we
V2 eae
fh hhh. = at ~~ -—
INSULATING
SUPPORT
52 ohm
COAX
Do not use a random length of wire for an antenna in the VHF bands. It is
imperative that “tuned” or “resonant” antennas be used for these fre-
quencies.
For
best
results,
we
highly
recommend
use
of
commercial
antennas.
The
antennas
available
ou
the
market
today
are
economical
and
come
with
all
the
necessary
instructions
and
matching
devices
for
greatest
efficiency.
When
performing
adjustments
on
a
commercial
antenna,
always
make
the
required
adjustments
with
an
SWR
meter
to
be
sure
you
obtain
optimum
results.
A
separate
RE
ground
is
not
required
for
your
transceiver,
However,
a
DC
ground
may
be
necessary
to
keep
the
chassis
at
ground
potential
and
avoid
the
possibility
of
minor
shocks
due
to
normal
transformer
leakage.
The
antenna
system
should
be
adequately
grounded;
the
transceiver
will
be
grounded
through
the
shield
of
the
coaxial
cable.
Always
use
a
lightning
arrester
for
your
antenna
system,

OPERATION — Continued
MOBILE
STATION
ANTENNAS
The
two
popular
antennas
for
6
meter
mobile
operation
ave
the
vertical
or
whip
antenna
aud
the
halo
antenna.
The
whip
antenna
is
more
efficient
than
the
halo.
It
is
vertically
polarized,
which
is
a
disadvantage
for
Noise,
sinee
man-ntide
noise
is
primarily
ver-
tically
polarized,
The
halo
provides
a
horizoutally
polarized
signal;
this
should
be
considered
if
you
intend
to
communicate
with
fixed
stations
(which
usually
use
hori-
zontally
polarized
anteunas).
Again,
we
recommend
that
you
use
commercial
antennas,
They
come
com-
plete
with
mounting
hardware
and
adjustment
instructions,
The
location
of
the
mobile
antenna
has
a
great
effect
on
the
antenna
effi-
cieney
and
directivity.
i
Antennas
mounted
in
the
center
of
the
roof
of
a
vehicle
will
radiate
equally
in
all
directions.
A
bumper
mounted
antenna
radiates
in
a
pattern
directly
in
front
of
and
to
the
rear
of
the
vehicle,
with
maximum
radiation
directly
away
from
the
vehicle.
Since
the
normal
Y.
wavelength
whip
antenna
is
too
long
(56”)
for
roof
mounting
on
a
vehicle,
the
antenna
is
shortened
aud
a
loading
coil
is
uti-
lized
to
provide
the
proper
cleetrical
length.
As
a
result,
the
over-all
efli-
cieney
is
redueed
and
the
nondireetional
advantage
is
defeated.
Thus,
the
bumper
mounted
whip
antenna
will
give
superior
results
in
most
cases.
A
few
general
rules
should
be
followed
for
proper
imstallation
of
the
mobile
antenna:
I.
Keep
it
as
far
as
possible
from
the
main
metal
bulk
of
the
vehicle.
im
Keep
as
much
of
it
as
possible
above
the
highest
point
of
the
vehicle
or
boat.
3.
During
operation
it
must
be
kept
vertical.
Thus
it
should
be
mechani-
‘ally
rigid
so
it
will
maintain
a
vertical
position
when
the
vehicle
or
boat
is
in
motion.
4.
Mount
it
as
faras
possible
from
sources
of
noise
(ignition
system,
gauges,
ele.)
and
convenient
for
transntission
line
routing
away
from
these
noise
sources.
An
antenna
mounted
in
a
boat
requires
a
ground.
Phis
can
be
cither
the
metal
hull
ov
ground
made
of
tin-foil
or
copper
shecting,
This
ground
should
cover
an
area
of
12
square
fect
or
more.
Be
sure
the
transceiver
has
an
adequate
ground
also.
MOBILE
INSTALLATION
CONSIDERATIONS
Safety
and
convenience
are
the
primary
cousiderations
for
mounting
any
piece
of
mobile
equipment.
All
controls
must
be
readily
available
to
the
operator
without
interfering
with
the
movements
necessary
for
sale
oper-
ation
of
the
vehicle.
Be
sure
all
cables
are
clear
of
the
brake
and
accelerator.
CAUTION:
Check
with
loeal
authorities
about
mobile
operations
restric-
tions:
some
states
prohibit
the
use
of
a
hand
bucrophone
while
a
vehicle
is
in
motion,
Also,
thought
must
be
given
to
the
convenience
of
passengers
will
they
have
adequate
leg
room
?
A
last,
and
extremely
important
requirement
is
the
ease
of
installation
and
removal,
Mount
the
transeciver
so
that
it
ean
be
slipped
in
and
out
very
casily,
The
most
common
mounting
position
for
a
transceiver
of
this
size
and
weight
is
directly
over
the
driveshaft
hump,
Due
to
the
weight
of
this
unit,
we
do
not
recommend
that
you
mount
it
suspended
from
the
dash.
Do
not
mount
the
transceiver
in
the
path
of
the
heater
air
stream.
Also,
avoid
mounting
ina
plice
that
will
interfere
with
the
glove
compartinent
orash
tray.
Be
sure
the
chassis
of
the
transceiver
is
eleetrically
couneeted
to
the
ground
system
of
the
vehicle
or
boat.
Use
a
separate
ground
wire
to
be
sure.
BATTERY
When
used
in
mobile
operation,
your
transceiver
must
obtain
power
from
Whatever
source
is
available
in
the
vehiele
ov
boat.
1a
most
eases
this
is
a
storage
battery,
The
power
required
by
vour
transeeiver
will
be
in
addi-
tion
to
the
power
normally
drawn
by
the
ignition
svstem,
lights
and
ae.
CeESSOLIeS,
This
extra
power
drain
must
be
carefully
considered
before
installings
vour
transceiver,
The
battery
inust
be
capable
of
handling
the
extra
load,
addi-
Hional
fusing
devices
may
be
required
and
the
generator
or
alternator
must
be
adequate
for
the
installation.

Also, before installing the transceiver, be sure the vehicle has the correct
ground system. Most vehieles niuumufactured in the United States since
1956 have a negative ground electrical system. Severe damage may result
if you attempt to use this transceiver on a positive ground system,
Do not allow the battery to beeome discharged by adding this extra load.
In cold weather this is especially important, because the power available
from a storage battery drops sharply as the temperature decreases, Lave
the battery cheeked before installing the transeeiver and also have the
regulator adjusted to compensate for this increase in current drain,
It will be a good idea to check the eurrent rating of the generator or alter-
nator, Be sure its current rating is not execeeded with the additional eur-
rent drawn by the transceiver, The current rating of the generator or
alternator should not be exceeded even under peak loads: the heat de-
veloped in the windings may permanently damage it.
You can use the auto accessory plug supplied to conbeet vour transeeiver
to the vehicle’s power source. However, it is better to conneet the DC
power cord directly to the accessory terminal of the ignition switch. This
will prevent unauthorized usage of the transeciver, and will also prevent
you from leaving the transceiver on unintentional,
NOISE
Your vehicle or boat can be the cause of mueh noise interference. Since
the receiver seetion of your transceiver is very sensitive, it will pick up
even the smallest noise signals and amplify them, A point worth mention-
ing is that the frequency components of ignition noise peak at about 50
me. Thus, ignition noise problems will be more prominent in the 6 meter
band than any other portion of the speetrum,
Remember,
your
transeeiver
his
a
very
seusitive
receiver
and
it:
will
pick
up
even
the
smallest
trace
of
ignition
noise,
Any
noise
that
vou
hear
in
the
transeeiver
is
almost
totally
from
external
sources,
The
receiver
itself
is
exceptionally
quiet.
Steady,
high
noise
levels
can
not
be
eliminated
by
internal
circuits
(sueh
as
the
ANI,
cireuit).
When
the
level
of
the
noise
approaches
the
level
of
an
incoming
signal
switching
in
the
ANL
will
re-
duee
the
level
of
the
signal,
along
with
the
level
of
the
noise.
Noise
prob-
lems
can
not
be
solved
internally
(in
the
transceiver);
they
must
be
solved
at
the
source
of
the
noise,
If vou wonder if the noise is from your ignition system, the transeeiver or
an external souree, try this simple test. Turn vour ignition switeh off and
set it to ACC Ciccessories), This turns off the ignition, but supplies power
to the transceiver, Most of the noise will disappear---indicating that the
source of noise is your ignition system,
This interfering noise can be generated anywhere in the electrical system
of the vehicle or boat. The first step in reducing or eliminating this noise
is to locate the souree of the uoise.
Ignition System
The most common source of noise is the ignition system, This noise ean be
identified by the fact that it varies with the speed of the engine. It con-
sists of a series of popping sounds oceurring at a regular rate that will
vary with the speed of the engine and stop when the ignition is turned off,
There are a uumiber of things that can be done to reduce this type of noise:
I. Use only the “radio suppression type” high voltage jguition wire.
Most new cars come already equipped with this type of wire.
2.
dnspeet
the
high
voltage
ignition
wire
and
all
conneetions
made
with
this
wire.
Old
ignition
wire
may
develop
leakage
resulting
in hash.
3.
Tf
noise
still
persists,
replace
the
spark
plugs
with
spark
plugs
that
have
suppressor
resistors
built-in.
Be
sure
to
use
the
correct
type
for
vour
vehicle.
The
best
solution
and
ost
nearly
perfect
cure
is
to
use
a
top-quality,
complete
ignition
system
shielding
kit.
We
highly
reeommend
use
of
one
such
as
the
Johnson/Ilallett
Kliminoise
ov
a
kit
of
comparable
quality.
IH
will
provide
maximum
suppression
of
all
ignition
noise.

MOBILE
INSTALLATION
CONSIDERATIONS
—
Continued
Generator
Probably
the
next
most
common
source
of
interference
is
the
generator.
Generator
noise
shows
up
as
a
musical
whine
that
is
present
whenever
the
engine
is
running.
The
pitch
of
the
whine
varies
with
the
speed
of
the
engine.
To
eliminate
this
type
of
interference,
connect
a
coaxial
type
0.5
pf
ca-
pacitor
from
the
ARMATURE
terminal
of
the
generator
to
the
metal
case
of
the
generator.
Also,
connect
a
high
quality
(mica)
0.001
pf
capacitor
across
(in
parallel
with)
the
0.5
pf
capacitor.
In
serious
cases
of
generator
interference,
it
may
be
necessary
to
install
new
brushes
on
the
generator.
This
will
be
especially
true
of
generators
in
older
vehicles.
Occasionally,
in
an
old
generator,
the
shaft
bearings
may
be
worn
to
a
point
where
they
add
to
the
noise
interference.
In
these
cases,
it
is
best
to
replace
the
generator.
Regulator
Regulator
noise
appears
as
a
“hash”
or
an
irregular
raspy
noise.
This
noise
can
be
eliminated
by
connecting
a
0.25
uf
coaxial
type
capacitor
from
the
battery
terminal
(BAT)
to
the
case
of
the
regulator
and
another
0.25
xf
coaxial
capacitor
from
the
generator
armature
terminal
(ARM)
of
the
regulator
to
the
case
of
the
regulator.
You
may
also
find
it
necessary
to
connect
a
3.3
ohm
carbon
resistor
in
series
with
a
0.002
pf
coaxial
capacitor
from
the
field
terminal
(FLD)
to
the
case
of
the
regulator.
Gauges
Another
possible
source
of
annoying
interference
is
the
gauges.
Gauge
noise
usually
shows
up
as
a
periodic,
rasping
sound,
When
in
doubt
about
gauge
interference,
install
a
0.1
ef
coaxial
capacitor
directly
from
the
“hot”
terminal
on
the
gauge
to
the
chassis
of
the
vehicle.
Also,
a
tachometer
can
be
a
source
of
noise;
install
a
0.1
vf
coaxial
capacitor
on
the
lead
from
the
ignition
coil.
10
Static Noise
The
discharge
of
static
electricity
developed
on
the
vehicle
may
cause
some
interference.
Static
can
be
developed
in
the
wheels,
by
the
rotation
of
the
tires
and
brake
drums.
This
type
of
interference
can
be
eliminated
by:
1.
Installing
wheel
static
collectors
under
the
hub
caps
of
the
front
wheels.
These
static
collectors
can
be
obtained
at
any
automobile
or
radio
parts
store.
2.
Inject
antistatic
powder
in
the
tires.
This
too
can
be
obtained
at
an
auto
parts
store.
The
body
of
a
vehicle
can
also
develop
static
when
driven
at
high
speeds.
This
static
electricity
discharges
off
the
end
of
the
antenna.
A
piece
of
vinyl
plastic
tubing
secured
over
the
end
of
the
antenna
will
effectively
reduce
this
type
of
interference.
Loose Bonds
Loose
linkages
or
bonds
on
the
vehicle
can
cause
interference.
This
will
be
especially
noticeable
when
driving
over
rough
roads.
To
climinate
this
type
of
noise:
1.
Tighten
up
all
bolts
and
linkage
connections,
2.
Use
braided
shield
to
bond
various
suspected
parts
to
the
frame
of
the
vehicle
(for
example,
and
especially,
the
tailpipe
and
muffler).
Generally
speaking,
interference
noise
can
be
generated
by
any
device
or
connection
that
carries
electrical
current.
Any
device
that
can
generate
a
spark
should
be
suspected.
Bypass
any
suspected
wire
to
the
frame
of
the
vehicle
with
a
high
quality
0.1
»f
capacitor
(preferably
the
coaxial
type).
For
additional
material
on
the
reduction
of
interference
noise,
we
suggest
you
refer
to
the
Editors
and
Engineers
Radio
Handbook
and
The
Radio
Amateur’s
Handbook
published
by
the
ARRL.
These
books
should
be
avail-
ble
at
most
local
libraries.

TELEVISION
Operation on the amateur VHF bands results in the greatest frequency
of TVE complaints, as compared to the more popular low frequency bands.
Fear of causing TVE has probably been a major factor for lack of universal
interest and activity on the VIFF bands. However, if you keep a few things
in
mind
and
are
prepared
to
provide
help
and
assistance
to
TV]
complain-
ants, your aggravation with this subject can be held to a minimum.
It is important to take a well-organized, common-sense approach to the
problem, Any TVI situation resolves itself into three areas:
1. The amateur’s transmitter.
2. The amateur himself,
3. The receiver.
The first and third subjects are purely technical and usually can be solved
quite easily. The second is one of personal relations and usually is the most
difficult. Unfortunately, because it is not technical, the amateur often does
not devote as much consideration to this most important part of the TVI1
problem,
Let’s consider them in the order mentioned:
TRANSMITTER
Keep your own signal clean! This should be the basic rule for every ama-
teur, especially the VHF man.
This transeeiver has been designed with this consideration uppermost. As
a result, you can be very confident that any TVI problem is not a fault of
your transmitter, unless it is malfunctioning.
However, let us mention a few things to aid you in your TVL investigation.
The prime TV problem will be noted on channel 2 (54 to 60 me). This is
not the fault of the transmitter, but rather due to the lack of selectivity
in the front end of the TV receiver (more of that later). Channel 2 inter-
ference can only be solved at the receiver.
Interference on other than channel 2 could possibly be solved at the trans-
mitter end. It could be caused by improper adjustment of T-6, the Butfer/
Doubler coupling transformer, This would result in coupling and radiation
INTERFERENCE
of harmonies other than the 2nd harmonic from V-8 Doubler stage. Recheck
the adjustment of T-6, following the instruetions given in the MAINTE-
NANCE seetion of this manual. A second solution is to use a low-pass filter
at the output of the transceiver. Use a filter with a sharp-cutolf frequency
of 52 to 56 me. Such a low-pass filter will not only filter out any harmonics
present in the output from the transmitter, but it will also filter out any
strong commercial (FM or TV) signal that might otherwise cause birdies
in the receiver.
THE OPERATOR
Very
seldom
is
the
operator
the
problem,
but
he
is
the
one
standing
in-
between
the
other
two
subjects—the
transmitter
and
the
receiver,
He,
somehow,
must
bridge
the
gap
so
he
can
advise
the
complainant
about
the
receiver,
The amateur is in a touchy situation, He is in the right and yet he is
blamed for the problem. He must be courteous and considerate.
Remember that your neighbor probably looks at your hobby, and you, with
a certain amount of distrust. You are out of the ordinary and maybe even
have a touch of the “mad scientist”. To say nothing of being the one to
blame for disturbing his favorite TV program!
Keeping this attitude in mind, when you receive a complaint, be under-
standing and do not be afraid to admit that your signal is the one that is
interfering
with
his
TV
reception.
Willingly
conduct
some
on-the-air
tests
to determine the actual nature and proof of interference.
Then, explain to the complainant that the problem is not in your trans-
mitter but most probably in the TV receiver. This is the touchy point. He
may have just purchased a new set, and will take it as a persona] insult.
Do not be condescending in your explanation. And above all, be ready and
willing to give him a demonstration that your own TV set is not upset by
your transmissions. This is the convincing proof. It is best if you have a
portable TV set so you can show him on your own location, as well as at
his home. The best demonstration would be with an older set. Once you
have won the contidenee of the complainant, and have proved to him that
your transmitter is uot at fault, you can get on to the real problem—
VW

TELEVISION
INTERFERENCE
—
Continued
THE RECEIVER
Surveys
have
proved
conclusively
that
the
majority
(more
than
90%)
of
TVI
problems
are
caused
by
design
deficiencies
in
the
front
end
of
the
TV
set.
Also,
over
90%
of
these
problems
can
be
solved
by
the
addition
of
a
high-pass
filter
at
the
antenna
input
terminals
of
the
receiver
TV
manufacturers
recognize
the
problem
and
most
of
them
will
supply
the
necessary
filter
upon
request.
Have
the
owner
of
the
TV
set
write
directly
to
the
manufacturer,
giving
the
model
and
serial
number
of
the
TV
set,
call
letters
of
the
amateur
station
involved
and
all
details
of
inter-
ference,
Usually
the
manufacturer
will
send
the
necessary
filter
with
in-
structions,
without
further
correspondence
or
fee.
If
the
owner
prefers,
suggest
that
he
purchase
a
high-pass
filter
such
as
the
Drake
TV-300-HP
or
an
equivalent
filter.
In
most
cases,
this
will
solve
the
problem
without
further
difficulty.
In
severe.
cases
of
interference,
it
may
be
necessary
to
install
a
quarter-wave
stub
cr
absorption-type
trap
at
the
antenna
input
terminals
of
the
receiver.
SOLDER
(BOTH SIDES)
TAPE
SECTIONS OF 300 Q TWIN LINE
PLACED ON EACH SIDE OF ANT
LEAD-IN
SOLDER (BOTH SIDES)
12 Va-WAVE TRAP
50
mc
TRAP
144
mc
TRAP
l-1
L-2
C-1
c-2
C-1
C-2
L-1
L-2
C-1-50pf
TUBULAR
CERAMIC
C-2
-3-1l2
pf
NPO
TRIMMER
L-1- 10 TURNS #24 WIRE
L-2-5 TURN #18 WIRE
WOUND ON C-1
WOUND 3/8" DIA 3/4" LONG
TUNE C-2 TO RESONATE AT 144mce
USE
GRID
DIP
METER
AND
ADJUST
COIL
TURNS
TO
RESONATE
AT
50
me
ABSORPTION TYPE TRAP
General Interference Information
If
your
TV!
problem
seems
to
be
of
a
serious
nature,
or
you
are
unable
to
convince
the
complainant
of
your
willingness
and
ability
to
assist
him,
contact
the
local
Amateur
Radio
Club
or
TVI
Committee.
Most
centers
of
population
have
an
Amateur
Radio
Club
which
has
organized
a
TVE
Com-
mittee.
They
will
usually
have
some
suggestions
and
through
an
organized
group,
May
be
able
to
solve
the
problem
better
than
an
individual.
If
there
is
no
FVL
Committee
in
vour
area,
you
can
always
contact
the
FCC.
They
normally
are
very
willing
to
help
and
can
supply
eonsiderable
beneficial
literature,
Occasionally,
a
particularly
difficult
TVE
problem
will
result
when
a
viewer
is
attempting
to
receive
television
signals
beyond
the
norma!
service
range
of
a
TV
broadcast
station.
In
such
a
case,
particular
care
must
be
taken
with
filters
at
the
reeciver.
Be
sure
the
filter
is
installed
as
close
as
possible
to
the
antenna
input
terminals
on
the
tuner,
not
just
at
the
antenna
ter-
minals
at
the
baek
of
the
set.
It
may
be
that
a
trap-type
absorption
filter
will
be
required.
Also,
a
better
TV
antenna
can
be
of
assistance.
Consider
re-orienting
the
position
of
your
6
meter
antenna.
Often
a
T'VI1
problem
persists
beeause
of
the
proximity
or
orientation
of
the
TV
and
6
meter
antennas.
Raising
or
lowering
or
moving
the
fransmitting
antenna
away
from
the
receiving
antenna
can
greatly
improve
the
TVL
eondition.
Severe
cases
of
TVE
may
require
an
AC
line
filter,
especially
if
the
TV
set
is
on
the
same
power
line
as
your
6
meter
transmitter.
Use
a
filter
such
as
illustrated,
or
a
commercial
line
filter,
Never
eonnect
the
center
lead
of
this
filter
directly
to
the
chassis
of
a
transformerless
(AC-DC)
set:
con-
nect
if
to
the
chassis
through
a
0.001
pf
mica
capacitor,
¥#

RFC
AC
LINE
INPUT
POWER
TO
TV
SET
OOSpt O05 pt
TO TV SET GROUND
1F EQUIPPED WITH
OOSpt 005 pt TRANSFORMER
RFC
RFC-
#18
ENAMELED
WIRE
CLOSE
WOUND,
1/2"
DIA.
3"
LONG
AC POWER LINE FILTER
Another
source
of
interference
can
be
carried
in
on
the
AC
power
line.
An
AC
line
filter
such
as
illustrated
ean
be
helpful.
Often,
bypassing
each
side
of
the
power
line
to
chassis
will
be
adequate.
In
extreme
eases
of
line
inter-
ference,
check
and/or
replace
all
power
supply
and
power
line
bypass
ca-
pacitors,
It
may
be
necessary
to
bridge
electrolytic
bypass
eapacitors
with
a
0.001
pf
dise
ceramic
to
act
as
an
rf
bypass.
When
you
install
a
filter
(AG
line
or
high-pass),
be
sure
to
provide
a
good,
short
electrical
ground
to
chassis.
For
the
high-pass
filters,
be
sure
to
place
the
filter
as
elose
as
possible
to
the
rf
input
transformer.
Sometimes
an
external
ground
connection
to
the
chassis
will
be
of
further
help.
Again,
when
the
receiver
is
transformerless
(AC-DC)
do
not
ground
the
filter
di-
rectly
to
the
chassis;
connect
it
through
a
0.001
nf
mica
capacitor.
If
vou
con-
nect
the
chassis
to
an
external
ground,
do
so
only
through
a
0.001
pf
mica
capacitor.
Interference
to
a
high-tidelity
or
stereophonie
amplifier
is
very
uncommon
at
lower
transmitter
power
levels,
but
here
are
a
few
pointers
to
cover
this
situation,
This
type
of
interference
is
due
to
rectification
of
the
rf
signal
some-
where
in
the
amplifying
circuitry.
Installation
of
a
simple
R-C
filter
will
normally
cure
this.
Use
a
47K
to
100K
resistor
in
series
with
the
grid
and
a
100
pf
bypass
from
grid
to
cathode.
The
standard
grid
re-
sistor
(from
grid
to
ground)
is
usually
in
the
range
of
5-10
meg:
it
ean
be
reduced
to
2
meg.
Ht
may
help
to
bypass
the
heater
of
this
tube
to
chassis
with
a
0.001
pf
capacitor.
Be
sure
all
components
of
the
systems
have
a
common
chassis
ground
connection,
Always
use
shielded
eables
for
interconnecting
components
of
the
system,
Also,
if
the
speaker
leads
are
excessive
in
length,
it
may
be
necessary
to
shield
them,
Ist AUDIO
47K
non
100 pf
R-C R.F. FILTER
All
of
these
suggestions
apply
not
only
to
interference
caused
by
6
meter
transmissions.
Many
of
these
pointers
apply
to
other
forms
of
interference.
Strong
loeal
commercia]
broadcasting
stations
can
cause
interference
to
TV
sets,
standard
AM
radios
and
stereo
systems,
Installation
of
the
R-C
filter
in
the
first
audio
stage
of
the
set
will
clear
up
most
of
these,
13

MAINTENANCE
ALIGNMENT
For this alignment procedure you need two VIT'VM’s and an accurate source
of RE signal (calibrated generator or crystals).
[] Remove the unit from the case.
| | Set the front panel controls as follows:
oN
TRANSMIT-RECEKEIVE to RECEIVES,
SPOT to OFF. , . ua
RF GAIN to maximum. :
? é
AF GAIN to maximum.
POWER to OFF,
[ ] Set ANL switch on the back to ON,
CAUTION: The voltages used in this unit are at a potential high enough
to be fatal. Use extreme care when working on the circuit or making ad-
Justments while the power is on.
[| Turn the POWER on and let the unit warm up for at least 5 minutes.
RECEIVER ALIGNMENT
IF Section
[| | Now carefully remove the 34.4 me ervstal from its socket on the con-
verter sub-assembly.
IMPORTANT NOTE
DO NOT MAKE ANY ADJUSTMENTS ON THE CONVERTER SUB-
ASSEMBLY, ALL NECESSARY ADJUSTMENTS HAVE BEEN MADE
AT Tih FACTORY. DO NOT TOUCH ANY OF THE SLUGS.
| | Connect a VT'VM to the AGC line (junction of R-16 and R-24).
14
[
|
Connect
the
output
of
the
signal
generator
to
the
terminals
of
L-1
which
have
a
shielded
cable
conneeted
to
them—ground
to
shield
and
hot
lead
to
center
conductor.
|
|
Adjust
the
signal
generator
for
1650
ke,
30%
modulation
with
400
cycles,
Adjust
the
output
level
of
the
generator
to
maintain
1.5
volts
DC
on
the
AGC
line.
The
output
of
the
generator
must
be
kept
to
a
level
where
the
AGC
voltage
always
remains
1.5
volts.
Adjust
the
top
and
bottom
slugs
in
T-1,
T-2
and
T-8
for
maximum
audio
output.
Connect
the
second
VEVM
across
the
speaker
for
an
ac-
curate
indication
of
maximum,
Remember
to
maintain
the
output
level
of
the
generator
to
a
point
that
results
in
an
AGC
voltage
of
~-1.5
volts.
[
|
Remove
all
test
leads
from
the
underside
of
the
chassis.
Replace
the
bottom
cover.
|
]
Replace
the
34.4
me
erystal
in
its
socket
on
the
converter
sub-assembly.
RF Section
[
]
Connect
the
output
of
the
signal
generator
to
the
ANT
connector.
{ ] Tighten the front trimmer of C-8, tuning capacitor.
NOTE:
In
place
of
the
signal
generator,
appropriate
crystals
can
be
used
with
the
SPOT
function
to
obtain
the
proper
signal
frequencies.
Break
the
B+
lead
to
V-9
(red
wire
to
L-4)
and
insert
a
47K
resistor
in
series
with
this
lead.
Now
with
the
SPOT
switch
on,
the
output
from
the
oscil-
lator/tripler
will
be
reduced
sufficiently
to
provide
a
signal
of
proper
strength.
It
may
be
necessary
to
vary
the
value
of
this
series
resistor
to
provide
a
signal
of
proper
strength.
When
using
the
SPOT
function,
use
the
S
meter
for
the
indicating
device
in all
the
following
steps.
For
the
best
results,
the
signal
should
be
just
strong
enough
to maintain
a
usable
indication
on
the
S
meter.
Thus,
it
would
be
best
to
use
a
Resistance
Sub-
stitution
Box
for
the
resistor.
[
|
Loosen
the
set-screw
on
the
bushing
of
the
tuning
dial.
Rotate
the
shaft
of
the tuning
capacitor
so
the plates
are
all
the way
open.
Now
rotate
the
tuning
dial
on
the
shaft
so
the
line
on
the
window
lines
up
with
the
division
marking
just
above
52
(mc)
on
the
tuning
dial.
Posi-
tion
the
dial
as
close
to
the
front
panel
as
possible,
without
rubbing,
and
tighten
the
set-screw.

[] Set the receiver tuning dial to 50 me,
[ | Set the signal generator to 50 me and the output level control for about
[ ]
5 pv output (or use an 8.33 me erystal and the SPOT function).
Adjust L-2 (receiver oscillater) for maximum indication on the VTVM
connected to the speaker terminals. Do not turn the slug in L-2 over
one turn in either direction for this adjustment.
NOTE: [ff the maximum indication in the above step can not be obtained
(J
("|
in less than one turn in either direction, perform the following:
Turn the slug in L-2 until it is all the way at the top (all the
way in).
Back the slug down into the form, past the first peak and ad-
just it to the second peak.
Proceed with the alignment.
Set the signal generator and receiver tuning dial to 52 me (or use an
8.666 me crystal and the SPOT function).
Adjust the front trimmer on the tuning capacitor (C-8B) for maxi-
mum indication on the VI'VM. Reduce the output from the signal gen-
erator to a level where the output on the VIT'VM remains in the same
range, A signal level of about 1 ,v will give best results.
Repeat the last five steps as required to obtain correct calibration on
the tuning dial.
Set the signal generator and receiver tuning dial to 51.7 me (or use an
8.617 me crystal and the SPOT function).
Adjust the rear trimmer on the tuning capacitor (C-8A) for maximum
indication on the VI'VM.
Set the signal generator and receiver tuning dial to 50.2 me (or use an
8.3867 me crystal and the SPOT function).
Repeat the last three steps to assure proper tracking of the tuning dial.
IMPORTANT NOTE: Again we remind you, do not perform any adjust-
ments on the converter sub-assembly. All necessary adjustments have been
made at the factory. The following information is given for reference only:
L-101 is peaked at 50.5 mc; L-102 is peaked at 51.5 mc; T-101 is peaked
at
50.6 me (with slug !, to 14” from top of form) ; L-108 is set to a point
where the oscillator oscillates reliably (about '4 turn past the start of
oscillation).
TRANSMITTER ALIGNMENT
[
Connect a dummy load or wattmeter to the ANT output connector.
[ | Three crystals are required for transmitter adjustments—one at the
L |
[|
[ ]
low end of the band, one in the center and the third at the upper end.
Plug the low frequency crystal into socket #1, center into #2 and the
upper into #3.
Position MULT in the center of its range.
Remove the bottom cover; turn the POWER on and let the unit warm
up for a minute or more.
Connect a VTVM to the junction of R-40 and C-48 (on T-6 doubler
transformer) and the ground lead to chassis ground. Set the range to
measure 0 to 70 volts DC.
Set CRYSTAL to #2 and set TRANSMIT-RECEIVE to TRANSMIT.
Peak L-4 (oscillator plate coil) for maximum indication on the VTVM.
Set CRYSTAL to #1. Peak MULT and peak the bottom slug of T-6
(doubler transformer) for maximum indication on the VTVM.
Set CRYSTAL to #3. Repeak MULT and peak the top slug of T-6 for
maximum indication on the VTVM.
Switch back and forth between #1 and #3 and readjust the coil slugs
(and MULT) to provide approximately the same voltage.
Peak LOAD and PLATE for maximum indication on the front panel
meter.
This completes the alignment of the transceiver. Further alignment should
not be necessary, even if tubes are replaced, with the possible exception
of V-1, the 2nd mixer. If you replace this tube, you may notice a slight
shift in the tracking—recheck those adjustments only (L-1, L-2 and the
trimmers on the tuning capacitors).
15

TROUBLE-SHOOTING INFORMATION
lligh-quality
parts
are
used
throughout
the
circuit;
thus,
very
little
serv-
ice
or
maintenanee
will
be
required.
H,
however,
any
problem
should
de-
velop,
voltage
and
resistance
charts
are
provided.
Variations
may
be
+
20%.
Most
trouble-shooting
should
be
the
standard
signal
tracing
type.
This
will
quickly
locate
the
stage;
voltage
and
resistance
measurements.
will
pin-
point
the
problem.
The
converter
can
be
isolated
from
the
circuit
following
by
connecting
an
antenna
to
the
primary
winding
of
L-1.
The
following
stage
is
tuneable
from
15.6
to
17.6
me.
Signals
in
this
frequeney
range
should
be
received
by
varying
the
tuning
capacitor,
This
indicates
that
all
stages
but
the
converter
are
operating
normally.
VOLTAGE CHART
PIN
oes i ee ee 2 3
V-1l | Receive | 84 1.211380 | 12.8)6.3
Aol eee AC_ [AC
V-2 | Receive 1.4 0 6.38 | 12.8 12380
_ AC [AC _
V-3
|
Receive
1.2
0
6
23/215
|70
|0
Jo
|—
J JAC FAC
V-4 | Receive i) 0516 0
oP kot AC
V-5 | Reeeive | -— 12.8 1360 | 340
Transmit} — 12.8 | 828 | 308
AC
V-6 | Receive 1.7 .65 | 0 0
Transmit] 90 0 1.05 | 0
Receive | 66 6.1 388 | 66
AC
Transmit] 7.7 6.1 153 | 7.7
arene) ee AG
Receive 9 [0 [1238]0
AC
Transmit| }>--7510 12.3 ]0
AC |
V-9 | Receive D6 0 12.3 |0
ee AC
Transmit|t> 15 1.08 12.3 10
AC
Converter Sub Assembly—-B | terminal, 225 volts Reecive,
3 volts Transmit.
All
voltages
taken
with
a
VP'VM
with
respect
to
chassis
ground,
tMeasured with a 47K isolating resistor (keep its leads to a minimum
length) in series with the VI'VM probe.
*DO
NOT
MEASURE,
You
may
measure
B+
on
the
B+
side
of
RFC-1.
16
RESISTANCE CHART
PIN
1
2 3
6
7
8
y
5AK*
[|
AT0K
|
400K*]
8
|
5AK*
|
900
0
82K
28meg]O
[8
*T
105K*[
0
|
as
2.6
meg
|
0 2
L20K*[
OQ
500K
I
meg}
2
O
|
600K
aoe
eee
NC
[8
450*
|
L.25K*
NC
[8
7
[330
[=
“|
830K
[|
47k
|
230K
*]
820K
**]
3.3K
4.8
NS
8
5OK
*
NS
0
Plate
NC—no connection
NS-—not signifieant
*—_with respect to Junction of CR-2 and C-58.
**__will
vary
with
setting
of
MIC
GAIN
control.
Resistance
readings
taken
with
a
VEFVM
with
respect
to
chassis
ground.
Controls
set
as
follows:
ANI-—ON
TRANSMIT-RECEIVES in RECEIVE
POWER OFF
SPOT OFF
RF and AF GAIN in maximum counterclockwise position
FRONT
TUBE LOCATION (bottom view)

m
v]
a a 7 rn ee ee, Smee
CIRCUIT DESCRIPTION
The
following
description
of
eireuit
function
is
given
to
add
{to
your
knowl
edge
of
vour
transeeiver.
It
will
also
help
vou
maintain
and
service
it.
RECEIVER SECTION
The
most
eritieal
portion
of
the
transeeiver
is
the
“front
end’
or
con.
verter,
This
section
has
been
carefully
prewired
and
aligned
to
assure
that
maximum
benefit
is
obtained
from
the
carefully
designed
circuitry,
Converter
The
input
signal
at
a
frequency
of
50
to
52
me.
is
amplified
by
V-10d.
In
V-10O2A
it
is
mixed
with
the
signal
generated
by
the
Ist
Oseillator
V-102B,
which
operates
at
34.4
me.
The
resulting
frequeney
is
in
the
range
of
15.6
to
17.6
me.
This
is
what
appears
at
the
output
of
the
eonverter,
L-101
is
the
RE
Input
coil
and
matehes
the
antenna
impedance
(30-90
ohms)
to
the
input
impedance
of
the
RE
Amplifier,
V-fL01,
V-101,
a
nu-
vistor,
is
operated
as
a
neutralized
triode.
The
nuvistor
assures
minimum
internal
noise,
and
the
standard
triode
aniplifier
arrangement
provides
the
required
gain,
The
combination
of
C-101
and
C-1028
form
the
bridge
neutralizing
circuit.
The
plate
eireuit
is
tuned
to
resonance
by
1-102.
The
triode
section
of
V-102
is
used
for
the
crystal-controlled
Ist
Oseil-
lator.
The
crystal
is
a
3rd
overtone
type,
cut
to
exactly
3-44
me.
The
cir-
cuit
is
a
standard
tuned-plate,
tuned-grid
oscillator.
The
plate
circuit
is
peaked
for
resonance
by
the
combination
of
L-108
and
(-112.
The
pentode
section
of
V-102
is
used
for
the
first
mixer.
The
signal
from
the
RE
amplifier
is
fed
direetly
into
the
grid
through
C-106.
The
oscillator
signal
is
coupled
into this
seetion
by
inter-eleetrode
capacity
in
the
tube.
The
plate
circuit
of
the
Ist
Mixer
is
tuned
to
the
difference
between
the
incoming
frequency
and
the
frequency
of
the
crystal
oscillator.
Thus,
it
is
tuned
to
the
range
of
15.6
to
17.6
me.
T-L01
not
only
serves
the
purpose
of
resonating
to
the
difference
frequeney,
but
it
also
matehes
the
output
impedance
of
the
Mixer
to
a
low-impedance
output
circuit.
This
low
output
impedanee
circuit
is
used
to
feed
the
Ist
LE.
to
the
2nd
Mixer
without
adverse
loading
effeets,
interaction
and
keeps
radiation
to
a
minimum,
All
of
these
things
are
important
to
maintain
complete
isola-
tion
of
the
converter
circuit
from
the
cirenitry
following.
;
cai
luad
tue
atte
LE
ONVEREER
Ub
ASE
MALY
ma
ESS
a8"
De
Teta
ae
See
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thr
we
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You
will
notice
that
the
power
for
the
converter
is
fed
through
.001
pf
feed-through
capacitors.
These
provide
adequate
RE
isolation
for
the
power
circuits.
It
keeps
the
R.F.
signals
inside
the
converter
from
feeding
back
into
the
power
supply
and
thus
into
other
circuits,
and
it
also
keeps
out
other
R.FL
frequencies
that
might
be
radiated
from
hearby
wiring.
Thus,
the
entire
converter
assembly
is
effectively
shielded
from
all
ex-
ternal
signals.
The
input
is
a
shielded
cable
and
the
output
is
a
shielded
cable.
Another
item
should
be
noted
here.
The
converter
has
a
2
me
band-pass.
This
is
achieved
through
careful
design
and
properly
peaked
resonant
cir-
cuits.
Hach
coil
must
be
peaked
at
the
frequency
noted
to
maintain
the
broad-band
characteristies.
17

CIRCUIT
DESCRIPTION
—
Continued
2nd Mixer and Oscillator
The
output
from
the
converter
sub-assembly
is
fed
through
a
low-imped-
ance
circuit
(a
shielded
cable)
to
the
primary
winding
of
the
2nd
Mixer
input
coil,
[-1,
This
coil
matches
the
low-impedance
feed
line
with
the
high
impedance
of
the
grid
cireuit
of
V-1.
The
resonant
frequency
of
this
circuit
is
varied
with
one
section
of
the
tuning
capacitor,
This
tuned
circuit
feeds
the
grid
of
V-1A,
the
2nd
Mixer.
The
triode
section
of
V-1
is
used
for
the
2nd
Oseillator,
which
is
the
tunc-
able
oscillator.
The
combination
of
1-2
and
the
tuning
capacitor
C-8B
with
its
associated
trimmer,
forms
the
resonant
circuit
for
the
oscillator.
The
circuit
is
a
shunt-fed
Hartley
oscillator.
Adequate
temperature
com-
pensation
is
provided
by
C-33.
The
output
of
the
oscillator
is
coupled
to
the
mixer
circuit
by
inter-electrode
capacitance
in
the
tube.
The
oscillator
operates
on
the
low
side
of
the
incoming
frequency..
The
RE
GAIN
control
is
in
the
cathode
circuit
of
the
2nd
Mixer.
Ht
con-
trols
the
gain
of
the
2nd
Mixer.
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T-1,
the
Ist
LF.
transformer
is
tuned
to
the
difference
frequency
of
the
tuneable
oscillator
and
the
incoming
signal,
1650
ke.
The
Intermediate
Frequency
amplifying
system
is
composed
of
three
double-tuned
circuits,
T-1,
T-2
and
T-3
and
two
high-gain
tubes,
V-2.
and
V-3.
The
6BZ6
is
a
semi-remote
cut-off
tube
to
allow
complete
AGC
control
of
the
signal.
These
two
stages
are
the
only
ones
controlled
by
the
AGC
voltage
developed
at
the
detector.
The
6BZ6
tube
is
a
high-gain
tube,
which
provides
more
than
adequate
gain
for
the
LE.
stages.
The
three
double-tuned
LF.
transformers
assure
narrow
bandwidth.
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Detector and Automatic Noise Limiter
The dual-diode, V-d, a GALS, is a high-perveanee tube, whieh makes it
particularly sensitive to low-level signals and contributes to the high-etli-
cieney
of
the
Deteetor
and
Automatie
Noise
Limiter
circuits.
The
first
section of this tube functions as a standard audio detector. The Automatic
Gain Control voltage is taken from this seetion, filtered and fed back to
the control grids of the I.E, amplifier tubes, V-2 and V-8.
The second section of V-t is used for a highly-etlicient series-gate noise
limiter,
There
are
two
primary
advantages
to
this
cireuit:
¥. It introduces negligible distortion even with high signal levels and
high
percentages
of
modulation.
This
is
a
shortcoming
of
many
noise
limiters;
that
is,
most
noise
limiters
distort
the
desired
signal
when the limiting action begins.
2. The reason for the low distortion is the self-adjusting feature of
this
circuit.
It
is
self-ceompensating
over
a
wide
range
of
signal
levels.
That
is,
as
the
amplitude
of
the
incoming
signal
varies,
the
clipping
or
limiting
level
varies.
The
output
from
the
Deteetor/ANL
eireuit
is
taken
from
pin
2,
and
coupled
to
the
AF
GAIN
control.
The
setting
of
this
control
determines
the
audio
voltage
fed
to
the
AF
Amplifier
and
Modulator
stages.
Audio Amplifier and Modulator
1,
of
V-6,
a
dual-triode,
is
used
for
low-level
audio
frequency
amplification.
You
will
notiee
that
double
by-pass
capacitors
are
used
for
the
cathode
resistor
of
all
the
audio
stages
and
the
final
RE
Amplifier.
The
large
value
is
for
audio
by-passing.
[fowever,
large
capacitors
typically
exhibit
indue-
tive-reactanee
at
RE
frequencies.
Thus,
it
is
necessary
to
provide
RE
by-
passing
with
a
ceramic
dise
capacitor.
The
remaining
',
of
V-6
is
used
for
the
microphone
pre-amplifier:
it
is
used
only
in
the
Transmit
function,
The
1000
pf
dise
capacitor
in
the
grid
circuit
rolls
off
the
high
frequeney
response
of
the
microphone.
Output
from
this
amplifying
stage
is
coupled
to
the
MIC
GAIN
control,
which
controls
the
amplitude
of
the
microphone
signal
passed
on
to
the
Audio
Frequency
Amplifier,
V-6A.
The
audio
Power
Amplifier/Modulator
stage
utilizes
a
rugged
6L6GC
tube.
This
is
a
tube
with
plenty
of
reserve
power
capabilities.
Ht
is
a
sensitive,
high-gain
tube with
more
than
enough
power
to
completely
modulate
the
2126
RF.
Power
Amplifier.
One
of
the
secondary
windings
of
T-5,
the
Output/Modulation
transformer,
is
used
to
drive
the
speaker.
A
front
panel
jack
provides
for
headphone
operation,
or
an
external
speaker.
The
390
pf
capacitor
in
the
grid
circuit
of
V-5,
provides
high
frequeney
roll-off,
thus
limiting
the
frequency
response
to
the
standard
300
to
3000
eps
required
for
maximum
intelligibility.
The
0.001
ef,
2KV
dise
capacitor
in
the
plate
circuit
of
V-5
is
primarily
for
protection
of
the
modulation
transformer
against
voltage
spikes.
When
switching
from
Receive
to
Transmit,
voltage
spikes
can
be
created
and
amplified
through
the
Audio
amplifying
stages
to
a
level
that
could
damage
the
transformer.
This
ca-
pacitor
charges-up
on
the
spikes,
thus
protecting
the
transformer,
The
bias
point,
plate
and
screen
voltage,
and
modulation
transformer
im-
pedance
have
all
been
carefully
designed
to
permit
the
Modulator
stage
to
clip
slightly
when
the
plate
voltage
swings
into
the
negative
half-cyele.
This
soft-clipping
prevents
distortion
due
to
over-modulation
in
the
nega-
tive
direction.
This
permits
the
positive
half-cycle
to
swing
up
to
full
{
modulation,
without
distortion
on
an
equal
amplitude
negative
swing.
4
This
results
in
greater
modulation
efficiency.
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19

CIRCUIT DESCRIPTION —- Continued
TRANSMITTER SECTION
RE
energy
is
developed
in
the
grid
circuit
of
the
Oseillator/Tripler,
V-9.
This
stage
is
operated
as
a
Colpitts
oscillator
with
the
plate
circuit
tuned
to
the
third
harmonie
of
the
grid
circuit.
The
capacitive
divider
network
is
composed
of
a
combination
of
the
capacity
of
the
shielded
cables
con-
nected
to
the
Crystal/VIFO
selector
switeh
and
C-55
and
C-56.
The
screen
grid
of
V-9
is
used
for
the
“plate”
of
the
oscillator
circuit.
The
plate
cireuit
is
tuned
to
the
third
harmonic
of
the
oscillator
frequency.
The
resonant
point
of
this
cireuit
is
controlled
by
the
setting
of
C-53,
the
front
panel
MULT
control.
There
are
two
advantages
to
this
pentode
oscillator/multiplier
circuit.
1.
The
separate
loads
for
the
circuits
(screen
for
the
oscillator
and
plate
for
the
tripler),
provides
isolation,
for
the
oseillater,
from
the
effects
of
changes
in
loading.
Thus,
the
oscillator
is
more
stable
in
frequency
and
reliability.
2.
The
isolation
and
separate
tuned
circuits
prevents
the
crystal
from
oscillating
in any
but
the
intended
mode.
With
VEO
operation,
the
pentode
function
(that
is,
screen
grid
isolation)
of
this
circuit
provides
additional
buffer
action
for
the
VFO.
This
makes
the
VFO
practically
immune
from
any
voltage
or
load
changes
in
the
transceiver,
The
next
stage
is
the
doubler;
which
uses
a
12AQ5
tube.
This
beam
power
pentode
tube
was
chosen
to
provide
adequate
power
to
drive
the
2K26
R.F.
Amplifier
to
its
full
capabilities.
Grid-leak
bias
is
developed
across
R-42,
and
is
present
only
when
grid
drive
is
present.
Note
that
the
doubling
is
done
in
a
separate
tube.
Often,
the
doubling
func-
tion
is
performed
in
the
final
stage
(at
the
expense
of
efficiency).
The
sepa-
rate
doubler
tube
provides
extra
isolation,
drive
and
minimum
harmonic
problems.
The
plate
circuit
of
the
doubler
stage
is
tuned
to
the
50
me
range,
The
inductive-coupled
double-tuned
circuit
provides
maximum
efficiency.
It
also
eliminates
the
possibility
of
harmonics
being
coupled
into
the
final
am-
plifier.
The
2626
is
a
compact,
high-efhiciency,
medium-power,
beam
power
pen-
tode,
It
is
particularly
suited
for
VIFF
use
up
to
150
me.
Because
of
the
metal
base
shield,
neutralization
is
not
required
even
when
operated
as
a
straight-through
amplifier
at
these
frequencies.
20
Operating bias for this tube is a combination of prid-leak and protective
‘athode self-bias. The cathode bias developed is sufficient to proteet the
tube from damage if grid drive ts lost.
The output circuit is the popular Pi matching network. Because it is basi-
eally an induetive coupling, it inherently suppresses harmonic radiation
(inductive reactance varies directly with frequency-- the higher the fre-
quency, for example, harmonies, the greater the inductive reactance). [1
also is a simpler form of output tuning.
The transmitter section is broad-banded to simplify tune-up and operating
frequency changes. This is achieved with the double-tuned ‘T-6 couphng
transformer. T-6 is stagger-tuned for broad band-width characteristics,
Throughout
the
design
of
the
transmitter,
very
careful
consideration
was
given
to
the
elimination
of
harmonic
generation,
coupling
and
radiation.
Any
one
of
these
could
cause
TV]
problems.
Some
of
the
features
that
help
to
climinate
any
such
problems
are:
1,
Electron
coupling
in
V-9,
the
Oscillator/Tripler.
This
provides
a
buffer
for
the
oscillator
circuit.
2.
A
tuned
circuit
is
used
in
the
plate
circuit
of
V-9.
This
resonant
circuit
provides
added
suppression
of
harmonics,
3.
The
separate
doubler
stage
provides
isolation
and
buffer
action.
4.
Double-tuned,
inductive
coupling
for
drive
from
the
doubler
to
the
final,
assures
harmonic
reduction
and
adequate
drive
over
the
de-
sired
frequency
spread.
5.
Straight-through
final
amplifier
maintains
minimum
harmonic
prob-
lems,
while
achieving
maximum
efficiency.
6.
Pi
network
output
cireuit
furnishes
proper
matching,
harmonic
sup-
pression
and
maximum
effieiency.
7.
The
entire
cireuitry
is
completely
shielded.
Tube
shields
are
used
for
all
tubes
and
the
entire
unit
is
shielded
with
the
wrap-around
case.