Page 4 Radio Service Bulletin No. 14
ADJUSTING COMPENSATING CONDENSERS.
The compensating should be done with the Receiver turned to some frequency between 1200 and
1400 kilocycles. Either an oscillator signal or a broadcast signalmay be used. Connect a good ground
to the Receiver. If an oscillator signal is used, connect the oscillator to the ANT terminal. If a broadcast
signal is to be used, connect the antenna to the ANT terminal.
When using the ear-method, the signal from the..oscillator should be very weak, and the volume
control of the Receiver turned on full. Tune the Receiver sharply. Using the fibre-wrench, adjust the
fourth Compensating Condenser until maximum volume is obtained. The fourth Condenser is the one
nearest the detector tube. Then adjust the other Compensating Condemiers in the same manner-
proceeding with the third, then the second, and then the first.
If the meter-method is to be used, tune in a strong broadcast signal between 1200 and 1400 kilo-
cycles, using the regular antenna connected to the Receiver. The volume control may be turned down
so that the volume is not annoying. Connect the negative terminal of a.250-volt high-resistance volt-
meter (preferably 1000 ohms per volt) to the ground terminal ofthe Receiver. Connect the positive
lead of the voltmeter to the screen-grid terminal of the third.24 tube. This can be done by wrapping a
fine wire around the prong of the tube, or by using an adaptor such as is commonly used for pick-up
work. This tube must be in the socket and operating when making the adjustment, and the tube shield
put back in place. · ·
Tune the Receiver sharply. Then check the adjustment of the Compensating Condensers, starting
with the fourth. Adjust each one to the point of maximum deflection of the voltmeter needle.
NEW. TUNING SCA,LE'ILLUMINATION.
The tuning scale used in the Models 96 and 96-A is translucent and is illuminated by means of a
pilot lamp placed inside the drum of the tuning condenser. In case it is necessary to replace the pilot
lamp, remove the screw faetening the lamp bracket to the condenser housing and bring the bracket out
over the top of the condenser. Replace the lamp and fasten the bracket in place again. This can be
done without removing the chassis from the cabinet.
REPLACEMENT PARTS
N~= . N~on
Fl~s. 3 and 4 Description Part No. Fl~s. 3 and 4 Description Part No.
CD Antenna Resistor . 3526 @ Volume Control . 4093
® First R. F. Transformer 3744-A @ By-Pass Condenser 3615-D
@ Tuning Condenser . . 4000-D @ Resistor 3768
© Compensating Condenser 3722-A @ Resistor . . 3542
© By-Pass Condenser . 3615-F @ Tone Control . · 4037-A
@ Resistor . . . . . 3542] @ Resistor 3542
0 Second R. F. Transformer . . 3744-B @ . Resistor 3766
@ By-Pass Condenser and Resistor 3615-C @ Resistor . . 3656
® By-Pass Condenser and Resistor 3615-B @ Input Transformer 3537
@) Third R. F. Transformer 3744~0 @ On-Off Switch . . . . . 4095
@ By-Pass Condenser . . 3615-~ @ Power Transformer (60 Cycle) . 3752
@ Fourth R. F. Transformer 3744-C @ Power Transformer (25 Cycle) . 3753
@ By-Pass Condenser . 3615-E @ C Resistor 3763
@ Resistor . . . . 3766 @ Choke . . . . . . . 3422
@ Fifth R. F. Transformer . . 3775-B @ Filter Condenser (60 Cycle). 3754
@ By-Pass Condenser and Resistor 3615-B @. Filter Condenser (25 Cycle). 3755
@ By-Pass Condenser and Resistor 3615-C @ Resistor. 3764
@ Condenser 3774 @ . B Resistor . . . 3762
@ Resistor 3769 @ Out~Put Transformer 2848
@ Resistor 3767 ·@ Field Coil . . . 2850
® Resistor . . . 3767 @ Voice Coil and Cone 2794-B
@ By-Pass Condenser 3583 @ Pilot Lamp ·. . 3463
@ Resistor 3767 @ Condenser (LOC) 3793-B
® Resistor 3768 Knob (Vol. Control) . 3579
@ Resistor . . . 3769 Knob (Tuning Condenser) 3580
® By-Pass Condenser ·3082 Dial Indicator 4006
® By-Pass Condenser 3082 Scale . . . . . . . . 4118
@ Condenser 3793-C Speaker Plug and Cable (Short) L-1101-A
@) Resistor 3769 Speaker Plug and Cable (Long) L-1102-A
NoTE: The first two Compensating Condensers© are 3772~A;the third and fourth Condensers are 3968-A.
PHILADELPHIA STORAGE BATTERY COMPANY
Ontario and C Streets, Philadelphia, Pa.
October, 1930 Form 2321 Printed in U. S, A,
