Philco 121 User manual

• • • • • • • • •
SERVICEBULLETIN No. 3O5 lo, membersol
RADIO MANUFACTURERSSERVICE
A PHILCO Service Plan
SPECIFICATIONS
TYPE OF CIRCUIT: A. C. operated; superheterodyne , circuit
with two tuning ranges, covering standard broadcast (540 KC. to
1720 KC.) and short-wave (5.8 MC. to 18.0 MC.) frequencies;
Electric Push-Button Tuning; Automatic Volume Control; and
Push-Pull pentode output.
The receiver is designed to operate from a "Philco Safety
Aerial," part No. 40-6371. This aerial system should be used to
obtain maximum performance from the receiver.
POWER SUPPLY: Voltage, 115 volts. Frequency, 50-60 cycles.
Power consumption, 80 watts.
INTERMEDIATE FREQUENCY: 470 KC.
TUNING RANGES: 540 KC. to 1720 KC.; 5.8 MC. to 18.0 MC.
PHILCO TUBES USED: 1-78, R. F.; 1-6A7, 1st detector and
oscillator; 1-78, I. F.; 1-6Q7G, 2nd detector, 1st audio Automatic
Volume Control; 1-6J5G, phase inverter; 2-42, push-pull output;
and 1-5Y4G, rectifier.
TUNING MECHANISM: Pulley and cable drive for Manual
tuning. Electric Push-Button for Automatic tuning.
CABINETS: Type "XX."
Adjusting Electric Push-Button Tuning
In order to set the Electric Push-Buttons correctly for each sta-
tion, the procedure as given below should be carefully followed.
Accurate adjustment of the buttons requires the use of a Philco
Model 077 Station Setter and a part No. 27-7059 insulated screw
driver .
(A) Select eight of the most popular stations received in the
locality and remove their call letters from the call letter sheets
supplied. Place the call letters in the windows above the buttons,
making sure that each button covers the frequency of the station
for which it is to be used. Two adjustment screws for each
button are located on the rear of the push-button unit. Each set of
screws is numbered and covers a frequency range as follows:
Push-Button Frequency Range
1 and 2 540-1030 KC.
3 and 4 670-1160 KC.
5 and 6 900-1470 KC.
7 and 8 1100-1600 KC.
Looking at the front of the cabinet, the first button on the left
is adjusted by set screw No. 1, the next button by set screw No. 2,
and the remaining buttons in the same order.
(B) Connect the aerial and ground to the "ANT" and "GND"
terminals of the receiver .
(C) Turn the receiver Tuning Range Selector to position 2
(Broadcast) and tune the receiver to the station to be set on the
first button .
(D) Plug the output 1eads of the Station Setter into the "High"
and "Gnd" jacks, and turn the output controls to maximum.
Turn the modulation control to "Modulation On." Connect the
output lead of the station setter to the "ANT" and "GND" ter-
minals of the receiver and tune to the frequency of the station
being received. As the indicator is slowly tuned through the fre-
quency of the station, there will be two points at which a whistle
will be heard, one above and one below the frequency of the station.
When the indicator is on the frequency of the station the whistle
will be eliminated and the modulated signal of the station setter will
then be clearly heard through the receiver.
(E) Turn the receiver Tuning Range Selector to position 1
(Push-Button) and press. in the first button. Using the part No.
27-7059 insulated screw driver; turn the No. 1 "OSC" screw until
the broadcast station identified by the station setter signal is tuned
to Maximum Volume.
(F) Remove the output lead of the station setter from the "ANT"
terminal of the receiver and turn the indicator of the Station Setter
off the frequency of the station. The program of the desired station
will then be heard in the receiver without the modulated signal.
(G) With the volume of the receiver low, slowly turn the No. 1
"OSC" screw back and forth until maximum output is received.
Repeat the same procedure for the No. 1 "ANT" screw.
After setting up the first station, the same procedure given under
(C) to (G) is used for tl)e other stations.
Copyright 1938, Philco Radio & Television Corp.
Phila., Pa.
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SCHEMATIC DIAGRAM MODEL 39-40
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EL£CTIIICAUTOMATICPUSH11./T'IQN\HT
DRIVE CORD SHOWN IN.
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CORRECT METHOD or INSTALLING DRIVE CORDS
ON TUNING CONDENSER DRUM
Replacement Parts
Model 39-40, Code 121
Schem . Part
No. Schem. Part
No .
1
2
3
4
5
6
7
I
9
10
11
12
13
14
15
16
17
11
19
20
21
22
23
24
25
26
27
21
29
30
31
32
33
34
35
36
37
31
39
40
41
42
43
44
45
46
47
41
49
50
51
52
53
54
55
56
57
51
59
60
61
62
63
64
Description
Antenna Transformer (Range 1,
Brdcst.) ...... . ... ......... .
Antenna Transformer (Range •2)
Condenser (.05 mf tubular) .....
Resistor (51,000 ohms, ½ watt).
Compensator (Range 2, S. W .).
Resistor (2.0 megohms, ½ watt).
Tuning Condenser . . . . . . . .... . .
Resistor (10,000 ohms, ½ watt).
R. F. Transformer (Range 1,
Brdcst .) .... . . .. ... .. ••. • • • •
Condenser (5 mmf mica) . ... . .. .
R. F. Transformer (Range 2,
32-3056
32-305 5
30-4519
33-351339
31-6212
33-520339
31-2296
33-310339
32-2379
30-1083
S. W .) ..................... 32-3046
Compensator (Range 2, S. W.) .. 31-6212
Condenser (.1 mf tubular) .. . . . . 30-4455
Condenser (.05 mf tub11Iar) ..... 30-4519
Compensator (two sections) ..... 31-6093
Oscillator Transformer (Range 1,
Brdcst.) ........ ... ......... 32-2120
Compensator . . . . . . . . . . . . . . . . . 31-6230
Oscillator Transformer (Range 2,
S. W.) ..... ... ........ .. : .. 32-3051
Condenser (.1 mf tubular) ..... . 30-4455
Resistor (32,000 ohms, ½ watt). 33-332339
Condenser (3425 mmf mica) . . .. 31-6263
Co.ndenser (250 mmf mica) .... . 30-1032
!st I. F. Transformer Assembly. 32-3079
Resistor (10,000 ohms, ½ watt). 33-310.139
Resistor (100.0 ohms , ½ watt) .. 33-210339
2nd I. F. Transformer. . . . . . . . . . 32-2582
Condenser (110 mmf mica) . . ... 30-1031
Resistor (330,000 ohms, ½ watt) 33-433339
Volume Control (2.0 megohms) .. 33-5286
Condenser (.003 mf tubular) .... 30-4580
Condenser (.01 mf tubular) .. ... 30-4581
Resistor (70,000 ohms, ½ watt). 33-370339
Condenser (.004 mf tubular) . . . . J0 -4578
Tone Control (3.0 megohms) .... 33-5287
.Condenser (110 mmf mica) ..... 30-1031
Condenser (.02 mf tubular) ..... 30-4481
Resistor (330 ,000 ohms, Vi watt) 33-433339
Resistor (2.0 megohms, ½ watt) . 33-520339
Resistor (1.0 megohm, ½ watt) .. 33-510339
Resistor (330,000 ohms , ½ watt) 33-433339
Resistor (1.0 megohm, ½ watt). 33-510339
Condenser (.01 mf tubular) . . ... 30-4581
Condenser (.1 mf tubular) .. .... 30-4455
Resistor (490,000 ohms, ½ watt) 33-449 .139
Condenser (.002 mf tubular) .... 30-4579
Resistor (490,000 ohms, ½ watt) 33-449.139
Resistor (5000 ohms, ½ watt) ... 33-250339
Condenser (.004 mf tubular) .... 30-4578
Resistor (99,000 ohms, ½ watt) . 33-399339
Resistor (45,000 ohms, ½ watt). 33-345339
Resistor (51,000 ohms, ½ watt) . 33-351339
Condenser (.004 mf tubul ar) ... . 30-4578
Resistor (490,000 ohms, ½ watt) 33-449319
Resistor (490,000 ohms, ½ watt) 33-449.139
Condenser (.003 mf tubular) .... 30-4469
Output Transformer ... . ...... 32-7981
Cone and Voice Coil Assembly for
Speaker (Part No. 36-1450) .. 36-4089
Condenser (.003 mf tubular) .... 30-4469
A. C. Switch ........ . ........ 42-1467
Condenser (.01 mf to .01 mf bake -
lite) . . . . . . . . . . . . . . . . . . . . . . . 3903 DG
Pwr. Trnsfrmr ., 115 v., 60 cycle 32-7998
Field Coil, Replace Speaker ..... 36-1450
Elect. Condenser (18 mf) . .-..... J0-2335
Elect . Condenser (25 mf) , 250 .. 30-2333
No.
65
66
67
61
69
70
71
72
72A
721
72C
72D
72E
72F
7:ZG
72H
73
73A
731
73C
73D
73E
73F
73G
73H
74
75
76
Descriptio,. No .
B. C. Resistor . . . . . . . . . . . . . . . . 33-3358
Resistor (4000 ohms, ½ watt) . . . 33-240339
Resistor (I 3,000 ohms, ½ watt) . 33-313339
Elect. Condenser (4 mf), 250. . . 30-2334
Pilot Lamp .• Dial . ............ 34-2064
Pilot Lamp . . . . . . . . . . . . 34-2064
Push-Button Switch ... , . . . . . . . 42-1462
Padder Strip A9"Cm., Complete . . 31-6259
Compensator No. 1 (540-1030 KC.)
Compensator No. 2 (540 -1030 KC.)
Compensator No. 3 (670-1160 KC.)
Compensator No. 4 (670-1160 KC.)
Compensator No. 5 (900-1470 KC.)
Compensator No. 6 (900-1470 KC.)
Compensator No. 7 (1100-1600 KC.)
Compensator No. 8 (I 100-1600 KC.)
Coil Strip Assembly (8 coils) . . . 32-3031
Coil No. 1 (540-1030 KC .) ..... 32-3042
Coil No. 2 (540-1030 KC.) ..... 32-3042
Coil No.. 3 (670-1160 KC.) . .. .. 32-3042
Coil No. 4 .(670-1160 KC .) . . ... 32-3042
Coil No. 5 (900-1470 KC.) . . ... 32-3041
Coil No . 6 (900-1470 KC.) . . . . . 32-3041
Coil No . 7 (1100-1600 KC .) ..... 32-3041
Coil No. 8 (1100-1600 KC .) .. ... 32-3041
Condenser (370 mmf silver mica) 30-1110
Condenser (370 mmf silver mica) 30-1110
Wave Switch . . .......... . .... 42-1461
Bezel . . . . . . . . . . . . . . . . . . . . . . . . 56-1104
Bezel Gasket .... .... ... .. ..... 27-9245
Bearing (Drum Shaft) ... .. .... 56-1036
Cable (Power) . . . . . . . . . . . . . . . . L-2778
Cable (Speaker) . ...... . .. . ... 41-3430
Coupling (Tuning Condenser) .. . 31-2291
Dial (Scale) ............ ... .. 27-5421
Dial Clamp .. . .. . .. .. . . ...... 56-1034
Dial Gasket ........ . ....... . . 27-9224
Dial Gasket ........... ... . .. . 27-9225
Dial Pointer ...... . •_.. ")".... .. 56-1033
Dial Drive Cord.(Tunmg ...... 31-2315
Dial Drive Cord. Pointer ...... 31-2316
Dial Drive Cord Spring ........ 28-8913
Disc Control (Tuning) .. ... .... 27-4766
Disc Control (Range Switch) ... 38-9702
Disc (Tone Control) . . . . . ... .. . 27-4764
Disc (Volume Control) .. . .. ... 27-4765
Drum Assembly (Tuning Con-
denser) ...... ... . .. .. .. .... 38-9661
Drum Bracket and Bearing (Tun-
ing Condenser) . . .......... . 38-9662
Shaft (Control Drums) ......... 28-6924
Socket Assembly Dial Lamp. . . . 38-9694
Socket Assembly Dial Lamp .... 38-9695
Socket (6-prong), 78-tube . ... . .. 27-6036
Socket (6-prong), Octal ...... .. 27-6086
Socket (7 -prong), Octal ... .. .. . 27-6053
Socket (7-prong), 6A7-tube .. ... 27-6107
Soeaker .... ... ....... . ... ... . 36-1450
Tab Kit . . . . . . . . . . . . . . . . . . . . . . 40-6392
Miscellaneous Parts
Grommet (Mtg. Push -Button
Switch) .......... ... ... .
Grommet (Mtg. Tuning Unit
Assy.) . .................. .
Grommet (Mtg . Tuning Unit
Assy.) ................ ... . .
Nut (A. C. Switch) ....... .. .. .
Nut (Speaker Mtg.) .. ... ..... .
Screw (Mtg. Chassis) ........ . .
Screw (Bezel) ........ . . . .... .
W ashe r (Speaker Mtg .) ....... .
Wa sher Rubber (Mtg. Chassis) .
Washer (A. C. Switch} ....... .
27-4610
3914
3915
W-1757
W-124
W-1345
W-1834
27-7467
27-4571
W-894
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Alignment of Compensators
EQUIPMENT REQUIRED:
(1) Signal Generator, Philco Model 077 Signal Generator which
has a fundamental frequency range from 115 to 36,000 KC. is the
correct instrument for this purpose.
OUTPUT METER: The Philco 027 Output Meter is connected
to the plate terminals of the type 42 tubes and adjusted for the
0 to 30 scale. After connecting the output meter, adjust the com-
pensators in the order as shown in the tabulation below. Locations
of the compensators are shown on page 3. If the outp.uJ meter
pointer goes off scale when adjusting the compensators, reduce the
strength of the signal from the generator.
(2) Output meter, Philco Model 027 Circuit Tester, incorporates
a sensitive output meter and is recommended.
(3) Philco Fiber Handle Screw Driver, part No. 27-7059 and
Fiber Wrench, part No. 3164.
SIGNAL GENERATOR RECEIVER
Opera • Special
Out put Dummy Adjust Instruc-
t10ns Dial Dial Control tions
Connections Antenna Compensators
to Receiver (Note A) Sett ing Setting Setting to Max. Reading
1 6A7 .1 mf 470KC. 580KC. Vol.Max. 26B,26A,
Range Switch 23B,23A
Broadcast
2 Ant. Ter. 150mmf 1550KC. 1550KC. " 15,7B, 7A See Note
BandC
3 Ant. Ter. 150mmf 580KC. 580KC. " 17 Roll Tuning
Condenser
4 Ant. Ter . 150mmf 1550KC. 1550KC. " 15
5 Ant. Ter. 400ohms 18.0MC. 18.0MC. Range Switch 15A, 12,5
S.W.
NOTE A-The "Dummy Antenna" consists of a condenser connected in
series with the signal generator output lead (high side) . Use the capacity
as specified in each step of the above procedure .
the dial, proceed as follows: With the tuning condenser closed (maximum
capacity), set the dial pointer on the extreme left index line at the low
frequency end of the broadcast scale . The arrangement of the drive cable
is shown on page 3.
NOTE B-Dial Calibration. In order to adjust the receiver correctly , the
dial must be aligned to track properly with the tuning · condense~ . To adjust NOTE C-Compensators (7A) and (7B) are located on top of the tuning
condenser. Compensator (7A) is the first one from the tuning drum side .
PHILCO AUTOMATIC TUBE TESTER
Model 033. For 115 Volts S0-60 Cycles
Positive, fast, accurate push-button testing of all type tubes. Ultra-
simplified contrnls plus automatic selection of voltage applied to tube being
tested, are the outstanding features of this remarkable new instrument.
Only two controls to set-tests any tube in a few seconds time! Applied
voltage selected by definite push-button controls.
Many other exclusive Philco features are built into this instrument. A
novel revolving chart indicates setting of all controls to make a complete
test of any tube.
Light weight, portable, rugged and attractive ; panel matches other Philco
test instruments. Large, easy-reading, illuminated indicating meter; neon
tube flash test for showing up "shorts." Carrying handle makes it equally
suitable for portable or counter use.
Net Dealer Price • • • • • • • • 15100
PHILCO RADIO AND TELEVISION CORPORATION
Parts and Service Division Philadelphia, Pa.
August, 1938 Printed in U. S. A.
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