DRS WJ-8770-1 User manual

FOR THE
WJ-8770-1
HF TRANSPORTABLE RECEIVER

SUPPLEMENT
FOR THE
WJ-8770-1
HF TRANSPORTABLE RECEIVER
WATKINS-JOHNSON COMPANY
700 QUINCE ORCHARD ROAD
GAITHERSBURG, MARYLAND 20878
04/81 1st Printing
08/ 82 2nd Printing

WJ-8770-1 SUPPLEMENT
WJ-8770-1 HF TRANSPORTABLE RECEIVER
1.1 GENERAL
The WJ-8770-1 HF
Transportable Receiver is virtually identical to the WJ-8770
model. There is but one basic difference, the ability of the WJ-8770-1 to accept power from a
24
Vdc battery pack.
1.2 FUNCTIONAL DESCRIPTION
The WJ-8770-1 differs physically from the WJ-8770 in that it has an additional
power input plug on the rear panel, designated jack J8. As can be seen from the Main Chassis
schematic, Figure 6-28, jack J8, when installed, ties to the input power line from the normal
power input jack, J1. The battery pack supplies 24 Vdc for operations, falling well within the
equipment's normal power requirements of 22 - 32 Vdc. There are no other wiring or physical
differences between the two models. Figure 2-3 shows the location of the battery power plug.
A
battery cover is available that provides a mounting for the battery and acts as a rear cover
for the receiver. .

FIELD SERVICE BULLETIN 7/10/81
WJ-8770-1 HF Transportable Receiver
A discrepancy was found regarding
the audio response measurement while testing
the production of the WJ-8770-1. A different set of data sometimes resulted when the BFO
had a positive or negative offset with the negative offset typically yielding an out of
tolerance result for the upper 3 dB limit.
An investigation of the product detector linearity, BFO level and variation, audio
roll-off etc. was conducted. Some product detectors were found to be oscillating at
approximately 100 MHz. Proper product detector gain/frequency response was restored
with the spurious oscillation suppressed giving symmetrical data well within specification.
The oscillation was suppressed
by lowering the terminating resistor (A4A1A10
R52) on the product detector's carrier input from 1 kn to lOOn. The source resister (A5A4
R19) on the BFO module was reduced from 510n
to 270S, to restore the proper drive level.
Approximately
25 receivers were shipped prior to the incorporation of these
changes, and will possibly have slightly reduced audio performance in the CW mode. Since
most CW operators work in the 400-2000 Hz range, there should be no problem. The audio
response
in other reception modes is not affected by these changes.
If there is a problem relating to this in the field, and units are to be modified,
there is no re-alignment or adjustments involved with the resistor changes.
The
customer may modify the units if he determines the above problem exists or
return the units to the factory for repair. If there are questions regarding this bulletin,
contact your local Watkins-Johnson Company Representative or the factory directly.

1.1 GENERAL
ADDENDUM I
30 July 1982
The following paragraphs describe the changes incorporated into the WJ-8770
HF Transportable Receiver. The changes made improve the overall function and
redesignate the equipment as the WJ-8770-1 HF Transportable Receiver.
The following paragraphs will describe the changes and if necessary illustrate the
additions. The change descriptions start with the main chassis and proceed in
reference designation sequence.
1.2 MAIN CHASSIS
1.2.1 In
order to agree with the WJ-8770-1 HF Transportable Receiver Main Chassis, the
following has been chJ;illged:
R4 -FROM:
TO:
R8 -FROM:
TO:
S4 -FROM:
TO:
Resistor, Fixed, Composition: 120n, 5%, 1/4W
P/N RCR07G121JS
Resistor, Fixed, Composition: 120Kn, 5%, 1/4W
P/N RCR07G124JS
Resistor, Fixed, Composition: 82n, 5%, 1/4W
PIN RCR07G820JS
Resistor, Fixed, Composition: 130n, 5%, 1/4W
P/N RCR07G131JS
Switch, Rotary, PIN 51530-{)1-2-GS
S
wi tch, Rotary, P/N 51530-{)1-2-{;N
1.3 INPUT CONVERTER TYPE 796099 (A3)
1.3.1 The Type 796099 Input
Converter has been changed to redistribute the power
supply load
from +15 Vdc to -15 Vdc. The parts list changes are listed below.
A1- FROM:
TO:
A2 -FROM:
TO:
C1- FROM:
TO:
C3 -FROM:
TO:
C5 -ADD:
1st Mixer/1st IF Type 34748-3
1st Mixer/1st IF Type 370417-1
2nd Mixer/2nd IF
Type 34748-3
2nd Mixer/2nd IF Type 370417-1
Capacitor, Ceramic, Feed-thru: 1000pF, GMV, 500 V
P/N 54-794-o09-102W,
Qty. 4
Capacitor, Ceramic, Feed-thru: 1000pF, GMV, 500 V
P
/N 54-794-o09-102W, Qty. 3
Same as C1
Not Used
Capacitor, Ceramic, Disc: 2200pF, 5%, 100V
PIN 8131-100-COGO-222U, Qty. 1
1-1

I-'
I
t-.:I
r-------------
I
I
.. -,
150 U 1
~
1 (01
1--------
r-------- ------
I I ----- --------=--~ I
I lO l1 CI •• , .10 I
.. . ",M I 80M B-II as ... 10 I. ~N510' Tt
"111 2 CI I
200 '" 'LI ~
IS~'.:': IN ~*" __ +-_---J
•• . O~'" n II~~~ JI
;, 'L-."~ ' IOO~~H'
••. ..... I I
L_
1ST IIU((""II1T "
,AIltT 570411' - 1
REr DESIO '''E'U( AI
CI I ..• 1
'0
I II I I I l t
1000 10," (5 10001 £1 L2" litIS
~I - - - ,I ''1'' I' T ;;;;~-+--+-----+----..
..
__ -1
a.
2N5101
c:'. to.? ...
I
I
I
I
1
JI 1 .. :~ •• I " I
.... .. ... ~ no .. _ ~
IN 1 C' 'I ~:C
I ". 1" ." I
•• ." :r'-'. I
I :r "I I
-.J
C1
l- Oh
l'
... __ .1.1.;<'..:..... .. '.
PAIn 510511-1 1It22: I
11 1000
tA»
0tj
~o
E.tt1
«z
...... 0
<.Od
~~
......
1
2ND "'H.' lMO " 10" 1
L___ .. "''',, ... ,,'' .00" I
L _______ ,,,. I "
____ -uSv
________ -1
NOTE :
UNLESS OTMERW'S( 5'[CI'IED :
., ,,[SIST .....CE I' IN OHIllS. :t:5"'.I~W .
"CAPACITANCE IS 'N ,F .
-'5V .... e ... D
Figure 1-1. Type 796099 Input Converter (A3)
Schematic Diagram 470388
.J

ADDENDUM I
30 July 1982
1.3.2
Refer to Figure 1-2 for Type 370417-1 1st Mixer/1st IF Location of Components.
Paragraph 1.3.2.1 is the new Parts List. Figure 1-1 is the Schematic Diagram.
Figure 1-2. Type 370417-1, 1st Mixer/1st IF (A3A1)
Location of Components
1-3

ADDENDUM I
30 July 1982
1 3 2 1
...
Type 3'1041 '1-1 1st Mixer/lst IF PC Assembly
I
REF
DESCRIPTION
DESIG
Cl
Capacitor, Ceramic, Disc: 1000 pF GMV 500 V
C2 Same as C1
C3
Capacitor, Variable, Ceramic: 2.5-9 pF 25 V
CRI
Diode
FLI
Filter BP, 42.905 MHz CF 40 kHz BW
Jl
Connector, Receptacle
J2
Same as Jl
Ll
Coil/Fixed 10 IlH 10%
L2
Same as Ll
Ql
Transistor
Q2 Transistor
RAI
Heatsink
Rl
Resistor, Fixed, Composition: 4.3 k, 5%, 1/4 W
R2
Resistor, Fixed, Composition:
8212, 5%, 1/4 W
R3
Resistor, Fixed, Composition: lOn, 5%, 1/4 W
R4
Resistor, Fixed, Composition:
150n, 5%, 1/8 W
T1
Transformer Assembly
UI Mixer/Balanced 2-500
MHz Double Bal
1-4
REF
DESIG PREFIX A3A1
QTY
MANUFACTURER'S
MFR.
RECM
PER
ASS'( PART NO.
CODE
VENDOR
2 B-GPIOOOPFP 91418
1 518-il00A2.5-9 '12982
1 IN4446 80131
1 92212 14632
2 34520-1 14632
2 1537-36 99800
1 2N2222A 80131
1 CP643 12498
1
Il18C
13103
1 RCR07G432JS 81349
1 RCR07G820JS 81349
1 RCR07GI00JS 81349
1
RCR05GI5IJS
81349
1 22295-52 14632
1
M9D
27956

ADDENDUM I
30 July 1982
1.3.3
Refer to Figure 1-3 for Type 370591 2nd Mixer/2nd IF Location of Components.
Paragraph
1.3.3.1 is the new Parts List.
+"""' r-r7""\
C19 ~ e
I M '-.../ o~
LT ~ ~19 -L3- T2
I -R9- I
IN
I" I -R8- ~ i
, )01 -R6- ({)g
5 ~ -R7- 03 L.... ______ O_U_T---I
I I Cl::; I -R~~2_ g-Rll I ~ FLl
~ 10 O. Q4 ~ -R23- on
\...J G tJ '-RS- C6 I - Ll0- l!!l
s y-y,~ I T3 CI[) I
I ~~o I -L9-
~ 02 D ~ T1 T( C13 )
1
-L6- Ul I
CcJ) -R22-
r-{14 .. ~ ! ~ -R21-
(Ii) R4- i I -RI8-
-R14- -R17- 3~7C: . ::S~!
Figure 1-3. Type 370591, 2nd Mixer/2nd IF (A3A2)
Location of Components
1-5

ADDENDUM I
30 July 1982
133 1
...
Type 370591 2nd Mixer/2nd IF Printed Wiri~ Assembly
I
REF
QTY
DESCRIPTION
PER
DESIG
ASS'1
Cl
Capacitor, Variable, Ceramic: 2.5-11 pF, 305 V 1
C2
Capacitor, Ceramic, Disc: 1000 pF,
GMV, 500 V 2
C3
Same as C2
C4
Capacitor, Ceramic, Disc: .01
~F, 20%, 50 V 5
C5
Same as C4
C6
Same as C4
C7
Same as C4
C8
Same as C4
C9
Capacitor, Ceramic, Disc: .1
~F, 20% 50 V 1
CI0
Capacitor, Ceramic, Disc: 4.7 pF, PORM 0.25 pF
100 V 1
Cll
Capacitor, Mica, Dipped: 47 pF, 2%, 500 V 1
C12
Capacitor, Ceramic Disc: 470 pF, 20%,1000 V 2
C13
Same as C12
C14
Capacitor, Variable, Ceramic: 9- 35 pF, 350 V 1
CI5
Capacitor, Mica, Dipped:
91 pF, 2%,500 V 2
C16
Same as CI5
C17
Capacitor, Mica, Dipped: 39 pF, 2%, 500 V 1
C18
Capacitor, Electrolytic, Tantalum:
100 ~F, 20%, 20 V 2
CI9
Same as C18
CRI
Diode HI Conductance PRY Silicon 1
CR2 Diode .040
pF 114 WGlass Hermetic Seal with
Dumet Lead 1
FBI
Ferrite Bread 3
FB2
Same as FBI
FB3
Same as FBI
FLI
Fil ter BP 10.7 MHz 1
Ll
Coil/Fixed 10 ~H 10% 4
L2
Same as Ll
L3
Same as LI
L4
Coil Fixed 0.56 lJH 15% 1
L5
Same as Ll
L6
Coil Fixed: 0.33 ~H 10% 1
L7
Coil Fixed Mold: 1.8
~H, 10% 1
L8
Coil Fixed Mold: .22
~H, 10% 2
L9
Coil Fixed Mold: .47
~H, 10% 1
L10
Same as L8
Ql
Transistor
1
Q2
Transistor
1
Q3
Transistor
3
1-6
PREF DISG PREFIX A3A2
MANUFACTURER'S
MFR. RECM
PART
NO. CODE VENDOR
538-o11B2.5-11 72982
B-GPI000PFP
91418
34453-1 14632
34475-1 14632
8108-100-COH0-479C 72982
CM05ED470G03 81349
BHD470-20PCT 91418
538-01109-35 7
29 82
CM05FD9IOG03 81349
CM05ED390G03 81349
I96D107X0020TE4 56289
IN4446 80131
5082-3039 28480
56-590-65-4A 02114
922ll
14632
1537-36 99800
202-ll
99848
1537-04 99800
1537-18 99800
1537-02 99800
1537-oS 99800
2N2222A 80131
CPS43 12498
2N5109 80131

REF
DESCRIPTION
DESIG
Q4
Same as Q3
Q5 Same as Q3
RAI
Heatsink
Rl
Resister, Fixed, Composition: 4.3 K,
596 1/4 W
R2
Resister, Fixed, Composition:
8211, 596, 1/4 W
R3
Resister, Fixed, Composition:
1011, 596, 1/4 W
R4
Resister, Fixed, Composition: 1.8 K,
596, 1/4 W
R5
Resister, Fixed, Composition:
6811, 596, 1/4 W
R6
Resister, Fixed, Composition: 3.3 K,
596, 1/4 W
R7
Resister, Fixed, Composition: 2.2 K,
596, 1/4 W
R8
Resister, Fixed, Composit~on:
1.0 K, 596, 1/4 W
R9
Resister, Fixed, Composition:
20011, 596, 1/4 W
RIO
Same as R3
Rll
Resister, Fixed, Composition:
4711, 596, 1/4 W
R12
Resister, Fixed , Composition:
4.711, 596, 1/4 W
R13
Same as R5
R14
Resister, Fixed, Composition:
390n, 596, 1/4 W
R15
Resister, Fixed, Composition: 330n,
596, 1/4 W
R16
Resister, Fixed, Composition:
15n, 596, 1/4 W
R17
Resister, Fixed, Composition: 2.0 K,
596, 1/4 W
R18
Same as R8
R19
Same as R15
R20
Same as R3
R21
Resister, Fixed, Composition:
l2n, 596, 1/4 W
R22
Same as R9
R23
Resister, Fixed, Composition:
6.8n, 596, 1/4 W
Tl
Transformer Assembly
T2
Transformer Assembly
T3
Transformer Assembly
Ul
MixerlBalanced 0.05-200 MHz
PREF DlSG PREFIX A3A2
QTY
MANUFACTURER'S
:~
PART NO.
1
lIl8C
1 RCR07G432JS
1 RCR07G820JS
3 RCR07GI00JS
1 RCR07G182JS
2 RCR07G680JS
1 RCR07G332JS
1 RCR07G222JS
2 RCR07GI02JS
2 RCR07G201JS
1 RCR07G470JS
1 RCR07G4R7JS
1 RCR07G391JS
2 RCR07G331JS
1 RCR07G150JS
1 RCR07G202JS
1 RCR07G120JS
1 RCR07G6R8JS
1 22295-53
1 22295-54
1 22295-55
ADDENDUM I
30 July 1982
MFR.
RECM
CODE
VENDOR
13103
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
81349
14632
14632
14632
1-7

ADDENDUM I
30 July 1982
1.4 DEMODULATOR/AGe AMPLIFmR TYPE 796113 (A4AIAIO)
1.4.1 The following components have been changed to upgrade the performance of this
module:
R7 -FROM:
Resistor, Fixed, Composition:
1000, 5% 1/4 W
PIN RCR07G101JS
QTY.7
TO:
Resistor, Fixed, Composition: 1000., 5% 1/4 W
PIN RCR07G101JS QTY.9
R29 -FROM:
Resistor, Fixed, Composition: 1.0KQ,
5% 1/4 W
PIN RCR07G102JS
QTY.5
TO:
Resistor, Fixed, Composition: 1.0KO,
5% 1/4 W
PIN RCR07GI02JS
QTY.3
R52 -FROM:
Same as R29
TO:
Same as R7
R54
-FROM:
Same as R29
TO:
Same as R7
1.5 SYNTHESIZER MOTHERBOARD TYPE 796117 (A5)
1.5.1
The following component has been changed to upgrade the performance of this
module:
J2 -FROM:
TO:
Connector, Receptacle, PIN 1-87227-0
Connector, Receptacle, PIN 2-87227-0
1.6 PHASE LOCK LOOP
TYPE 796115 (A5A2Al)
1.6.1
The following components have been changed to upgrade the performance of this
module.
Rl- FROM:
TO:
R9 -FROM:
TO:
1-8
Resistor, Fixed, Composition: 1.0KQ, 5% 1/4 W
PIN RCR07G102JS QTY.3
Resistor, Fixed, Composition: 1.0Ko., 5% 1/4 W
PIN RCR07GI02JS QTY.2
Same as Rl
Resistor, Fixed, Composition: 3900., 5% 1/4 W
PIN RCR07G391JS

ADDENDUM J
30 July 1982
1.7 VCO ASSEMBLY TYPE
796131 (A5A2A2At)
1.7.1 The following components have changed to upgrade the performance of this
module:
CR1-
CR2 -
CR3-
CR4 -
C1-
Q2-
Q3-
FROM: Diode, PIN 1N4446, QTY 3
TO: Diode, PIN BBI09/Yellow, QTY 1
FROM: Same as CR1
TO: Diode, PIN MPN3401, Qty 3
FROM: Same as CR1
TO: Same as CR2
FROM: : Diode/Varicap, PIN BB109/Yellow
TO: Same as CR2
FROM: Capacitor, Ceramic, Disc: 1000pF, GMV, 500V
PIN B-GP1000PFP QTY 13
TO: Capaci tor, Ceramic, Disc: 1 OOOpF, G MV, 500V
PIN B-GP1000PFP QTY 12
FROM: Transistor, PIN 2N3251, QTY 2
TO: Transistor, PIN 2N3251, QTY 1
FROM: Same as Q2
TO: Transistor, PIN 2N3906
1.8 2nd LO SYNTHESIZER TYPE
796107 (A5A3)
1.8.1 The following components have been changed to upgrade the performance of this
module.
Refer to Figure 1-4 for the new Location of Components.
C1-
FROM:
TO:
C25 -FROM:
TO:
R9 -FROM:
TO:
R70 -FROM:
TO:
Capacitor, Ceramic, Disc: O.lpF, 10%, 50V
PIN 8121-o50-X7RO-104K, QTY 14
Capacitor, Ceramic, Disc: O.lpF, 10%, 50V
PIN 8121-o50-X7RO-I04K, QTY 15
Same as C1
Same as C2
Resistor, Fixed, Composition: 1.0KQ, 5% 1/8 W
PIN RCR05G102JS QTY.5
Resistor, Fixed, Composition: 1.0KQ, 5% 1/8 W
PIN RCR05G102JS QTY.4
Same as R9
Resistor, Fixed, Composition: 560n, 5%, 1/8W
PIN RCR05G561JS
1-9

ADDENDUM I
30 July 1982
U6 -
Figure 1-4. Type 796107, 2nd LO Synthesizer (A5A3)
Location of Components
FROM:
TO:
Spacer/Hex, P/N 8213-55-0440-7
IC, Divide by 20, P/N SP8657M
1.9 BFO 3rd LO TYPE 796109 (A5A4)
1.9.1 The following components have been changed to upgrade performance of this
module:
C12 -
FROM:
TO:
C18 -. FROM:
TO:
1-10
Capacitor, Ceramic, Disc: .47pF, 20%, 50V
P/N 34452-1, QTY 2
Capacitor, Ceramic, Disc: .47pF, 20%, 50V
P /N 34452-1, QTY 3
Capacitor, Electrolytic, Tantalum: 100pF, 20%, 20V
P/N 196DI07XZ0020TE4, QTY 2
Capacitor, Electrolytic, Tantalum: 100pF, 20%, 20V
P /N 196DI07X002TE4, QTY 1

1.10
1.10.1
1.11
1.11.1
C50 -
-nOM:
TO:
R19 -FROM:
TO:
Same as C18
Same as C12
Resistor, Fixed, Composition: 510Q, 5%, 1/4W
PIN RCR07G5llJS
Resistor, Fixed, Composition: 270Q, 5% 1/4W
PIN RCR07G271JS
AUDIO AMPLIFIER
TYPE 796116 (A9)
ADDENDUM I
30 July 1982
The following
components have been changed to upgrade the performance of this
module:
R3 -FROM:
,Resistor, Fixed, Film: 6.81KQ, 1%, 1/10W
PIN RN55C68llF
TO: Resistor, Fixed, Film: 68.1Ko, 1%, 1/10W
PIN RN55C6812F
R7 -FROM: Resistor, Fixed, Film: 9.09Ko, 1%, 1/10W
PIN RN55C9091F
TO:
Resistor, Fixed, Film: 90.9KQ, 1%, 1/10W
PIN RN55C9092F
FRONT COVER ASSEMBLY WITH REMOVABLE SPEAKER
TYPE 796140-2 (All)
Refer to paragraph 1.11.2 for the new Parts List. Figure 1-5 is the location of
Components following the Parts List. Subassemblies follow (All) in Reference
Designation sequence:
(AllA1) - Speaker Amplifier Assembly, Type 796134-3
(AllA1A1) - Speaker Amplifier P.C. Assembly, Part 270784-1
1-11

ADDENDUM I
30 July 1982
1.11.2
TYPE 796146-2, FRONT COVER ASSEMBLY _/REMOVABLE SPEAK ASSEMBLY REF DESIG PREFIX A1l
REF
QTY
MANUFACTURER'S MFR .
RECM
DESCRIPTION
PER
DESIG
ASS't
PART NO.
CODE
VENDOR
Al Removable Speaker Assembly 1 796134-3
14632
1-12

1 11 2 1 Type 796134-3 Removable H0U5i~ Assembly with Speak Amp}
..
I
REF
QTY
DESCRIPTION
PER
DESIG
ASS\'
Al Speaker Amplifier PC Assembly 1
LSI
Speaker 1
PI
Plug Multipin 1
Rl
Resistor, Fixed, Composition: 50 K, 10%, 1 W 1
ADDENDUM I
30 July 1982
REF
DESIO PREFIX A11Al
MANUFACTURER'S
MFR.
RECM
PART NO.
CODE
VENDOR
270784-1 14632
25A070T 74199
OC329 25330
70A3N056L503A 01121
1-13