The Models 88 and 190 are Table and Console Receivers respectively. The chassis employed in both are identical and interchangeable, but the loudspeakers differ, as will be seen by reference to the above data.
ALIGNMENT PROCEDURE.
Alignment should only be necessary when adjustments have been altered from the factory setting or when repairs have been made to the tuned circuits. Climatic conditions should not seriously affect the receiver.
It is important to apply a definite procedure, as tabulated, and to use adequate and reliable test equipment. Instruments ideally suited to the requirements are the A.W.A. Junior Signal Generator, Type 2R3911, or the A.W.A. Modulated Oscillator, Type C1070. An
output meter is necessary with both these instruments. If the Type C1070 test oscillator is used, see that a 250,000 ohms resistor is connected between the output terminals and, for Short Wave alignment, a 400 ohms non-inductive resistor in series with the active output lead of the instrument.
Connect the ground connection of the test instrument to the receiver chassis.
Perform alignment in the proper order, starting from No. I and following all operations across, then No. 2, etc. Adjustment locations are shown in the layout diagrams. Keep the Volume Control set in the maximum clockwise position, and regulate the output of the test instrument so that a minimum signal is introduced to the receiver to give a standard indication on the output meter. This will avoid A.V.C. action and overloading.
When the receiver has been satisfactorily aligned, seal the adjusting screws with a small quantity of celluloid cement to eliminate the possibility of them shifting and also to indicate whether they have been tampered with after servicing.
ADJUSTING TOOLS.
Two tools, which have been specially designed for alignment purposes, may be obtained from the Service Department of the Company. One is for adjusting and locking air-trimmer condensers, and the other is a non-metallic screwdriver for adjusting the cores within the I.F. transformers and the broadcast oscillator coil. The part number of the former is No. 5371 and the latter No. 5372.
VIBRATOR POWER UNIT.
The silent and efficient operation of this unit is the result of the care taken in its development. In servicing, therefore, the following advice may be followed to ensure continued satisfaction.
Don't tamper with or attempt to adjust a vibrator suspected of being faulty. Replace it with one known to be in good order, and of the type specified under "Electrical Specifications." Make sure before installing the replacement that the clips attached to the socket will press firmly and make good contact against the vibrator case.
If a component is removed during servicing, replace it in its original position and connect it to the original points. It will be noticed that there is only one earth connection between the Vibrator Power Unit and the Receiver chassis, and that it terminates in the Vibrator Unit at a point on the chassis near where the components of the unit are earthed. That this be the only earth lead and that the earthing point should not be changed is most important.
Vibrator Power Unit Layout Diagrams.
ALIGNMENT TABLE
|
Test Inst. Connection
to Receiver. |
Test. Inst.
Setting. |
Receiver Dial
Setting. |
Circuit to
Adjust. |
Adjustment
Symbol. |
Adjust to
Obtain |
|---|---|---|---|---|---|
| *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s .†† | 3rd I.F. Trans. | LI3 | Max. (Peak) |
| *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s .†† | 2nd I.F. Trans | L12 | Max. (Peak) |
| *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s.†† | 2nd I.F. Trans. | LII | Max. (Peak) |
| *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s.†† | Ist I.F. Trans. | LIO | Max. (Peak) |
| *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s.†† | Ist I.F. Trans. | L9 | Max. (Peak) |
| Repeat the | above adjustments be | fore proceeding. | |||
| Aerial Term | 600 Kc/s. | 600 Kc/s.† | Oscillator | Core L6 | Max. (Peak) |
| Aerial Term | 1500 Kc/s. | 1500 Kc/s. | Oscillator | C5 | Max. (Peak) |
| Aerial Term | 1500 Kc/s. | 1500 Kc/s. | Aerial | C2 | Max. (Peak) |
| Re | peat adjustments 6, 7, | and 8. | |||
| Aerial Term | 15M. | 15M. | Oscillator | C7 | Max. (Peak)** |
| Aerial Term | 15M. | 15M.‡ | Aerial | C3 | Max. (Peak)*** |
|
Test Inst. Connection
to Receiver. *6J8G Grid Cap *6J8G Grid Cap *6J8G Grid Cap *6J8G Grid Cap *6J8G Grid Cap Aerial Term Aerial Term Aerial Term Aerial Term Aerial Term |
Test Inst. Connection
to Receiver.Test. Inst. Setting.*6J8G Grid Cap455 Kc/s.*6J8G Grid Cap455 Kc/s.Repeat the 600 Kc/s.Repeat the 1500 Kc/s.Aerial Term1500 Kc/s.Rerial Term15M.Aerial Term15M. |
Test Inst. Connection
to Receiver.Test. Inst. Setting.Receiver Dial Setting.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††AbJ8G Grid Cap455 Kc/s.Past 550 Kc/s.††AbJ8G Grid Cap455 Kc/s.Past 550 Kc/s.††AbJ8G Grid Cap455 Kc/s.Past 550 Kc/s.††AbJ8G Grid Cap455 Kc/s.Past 550 Kc/s.††AbJ8G Grid Cap455 Kc/s.Past 550 Kc/s.††AbJ8G Grid Cap455 Kc/s.Past 550 Kc/s.††Abj8G Grid Cap455 Kc/s.Past 550 Kc/s.††Abj8G Grid Cap455 Kc/s.Past 550 Kc/s.††Abj8G Grid Cap455 Kc/s.Past 550 Kc/s.††Abj8G Grid Cap455 Kc/s.1500 Kc/s.Abj8G Grid Term1500 Kc/s.1500 Kc/s.Abj8G Grid Term15M.15M.Abj8G Grid Term15M.15M.‡ |
Test Inst.
to Receiver.Test. Inst. Setting.Receiver Dial Setting.Circuit to Adjust.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††3rd I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††2nd I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††2nd I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††2nd I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††2nd I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††1st I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††Ist I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††Ist I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††Ist I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††Ist I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††Ist I.F. Trans.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††Ist I.F. Trans.Repeat the above adjustments before proceeding.Aerial Term1500 Kc/s.1500 Kc/s.Aerial Term1500 Kc/s.1500 Kc/s.AerialRepeat adjustments 6, 7, and 8.Repeat adjustments 6, 7, and 8.Aerial Term15M.15M.‡AerialAerial Term15M.15M.‡Aerial |
Test Inst. Connection
to Receiver.Test. Inst. Setting.Receiver Dial Setting.Circuit to Adjust.Adjustment Symbol.*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††3rd I.F. Trans.L13*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††2nd I.F. Trans.L12*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††2nd I.F. Trans.L11*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††2nd I.F. Trans.L11*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††1st I.F. Trans.L10*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††Ist I.F. Trans.L9*6J8G Grid Cap455 Kc/s.Past 550 Kc/s.††OscillatorCore L6Aerial Term600 Kc/s.600 Kc/s.†OscillatorC5Aerial Term1500 Kc/s.1500 Kc/s.AerialC2Repeat adjustments 6, 7, and 8.Repeat adjustments 6, 7, and 8.C7Aerial Term15M.15M.‡AerialC3 |
* With grid clip connected. A .001 mfd. condenser should be connected in series with the active output lead of the test instrument.
† Rock the tuning control back and forth through the signal. Reset the dial pointer to 600 Kc/s., if necessary. The pointer is soldered to the control wire and may be moved by applying a hot soldering iron to the connection.
** Use minimum capacity peak if two peaks can be obtained.
*** Use maximum capacity peak if two peaks can be obtained. Check for image signal by tuning the receiver to approx. I6M. It may be necessary to increase the output of the test oscillator to receive the signal.
# Rock the tuning control back and forth through the signal.
t With tuning condenser plates in full mesh.
Layout Diagram (Underneath View)
Layout Diagram (Top View), Showing Battery Connections.
SOCKET VOLTAGES.
| ۷ | ALVE. |
Bias
Volts |
Grid to
Chassis Volts |
Plate to
Chassis Volts |
Plate Cur
rent to M.A. |
- ment
Chassis Volts |
|
|---|---|---|---|---|---|---|---|
| 6J8G | Converter |
M.W.
S.W. |
3†
3† |
93
93 |
138
134 |
1.0
1.3 |
6 |
| Oscillator |
M.W.
S.W. |
_ | 135 |
4.5
4.5 |
|||
| ID5G | I.F. Amp. |
M.W.
S.W. |
0 |
27
35 |
140 | 1.2 | 2.0 |
| ID5G | I.F. Amp. |
M.W.
S.W. |
-2‡*
0 |
27
35 |
140 |
0.7
2.0 |
2.0 |
|
1K7G
1G5G |
2nd Det.
Output |
м.W.
S.W. |
-2‡
-13.5 -13.5 |
30
140 135 |
22
134 130 |
0.35
9.8 9.0 |
4.0
6.0 |
Measured with 1000 ohms per volt meter.
† Cathode to chassis.
‡ Control grid to negative filament.
* Cannot be measured with ordinary voltmeter.
Measured with Volume Control maximum clockwise. No signal input.
MECHANICAL REPLACEMENT PARTS
Part No.
| DESCRIPTION. Part No. DESCRIPTION. Part No. Pointer (Red) and Saddle, with Drive Wire 6629 Range Switch 8110 Drive Wire Tension Spring 6641 Battery-Tone Switch 8111 Drive Wire Jockey Pulleys—Large 6246 Tuning Knob 8075 Drive Wire Jockey Pulleys—Small 7885 Range Switch Knob—Outer 6625 Pointer Drive Drum 8030 Volume-Battery-Tone Control Knob—Outer 5625 Main Drive Segment 8037 Volume-Battery-Tone Control Knob—Inner 4589 Main Drive Spindle Assembly 8035 Valve Socket ((Lushion)) 7327 Vibrator Socket 8155 Valve Socket 8498 Dial Scale 8155 Valve Coilps 7459 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 7251 | TUNING MECHANISM. | MISCELLANEOUS. | |||
|---|---|---|---|---|---|
| Pointer (Red) and Saddle, with Drive Wire 6629 Range Switch 8110 Drive Wire Tension Spring 6641 Battery-Tone Switch 8111 Drive Wire Jockey Pulleys—Large 6246 Tuning Knob 6475 Drive Wire Jockey Pulleys—Small 7885 Range Switch Knob—Outer 6625 Pointer Drive Drum 8030 Volume-Battery-Tone Control Knob—Outer 5625 Main Drive Segment 8039 Volume-Battery-Tone Control Knob—Inner 4589 Main Drive Spindle Assembly 8035 Valve Sockets (4) 4704 Intermediate Drive Gear Assembly 8037 Valve Socket (Cushion) 7327 Dial Scale 8155 Valve Clips 8498 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 7251 | DESCRIPTION. | Part No. | DESCRIPTION. | Part No | |
| Drive Wire Tension Spring6641Battery Cable6212Drive Wire Jockey Pulleys—Large6246Loudspeaker Cable6475Drive Wire Jockey Pulleys—Small7885Tuning Knob Clip7686Pointer Drive Drum8030Range Switch Knob—Unter5625Main Drive Segment8039Volume-Battery-Tone Control Knob—Inner4589Main Drive Spindle Assembly8035Valve Sockets (4)4704Intermediate Drive Gear Assembly8037Valve Socket (2ushion)7327Valve Sockets8155Valve Clips7459Dial Lamp Sockets4195Loudspeaker Cone Assembly—Model 1907251 | Pointer (Red) and Saddle, with Drive Wire | . 6629 |
Range Switch
Battery-Tone Switch |
. 8110
. 8111 |
|
| Drive Wire Jockey Pulleys—Large 6246 Tuning Knob 8075 Drive Wire Jockey Pulleys—Small 7885 Range Switch Knob—Outer 7686 Pointer Drive Drum 8030 Volume-Battery-Tone Control Knob—Outer 5625 Main Drive Segment 8039 Volume-Battery-Tone Control Knob—Inner 4589 Main Drive Spindle Assembly 8035 Valve Sockets (4) 7929 Intermediate Drive Gear Assembly 8037 Valve Socket (Cushion) 7327 Dial Scale 8155 Valve Clips 8498 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 7251 | Drive Wire Tension Spring | . 6641 |
Battery Cable
Loudspeaker Cable |
. 6212
. 6475 |
|
| Drive Wire Jockey Pulleys—Small 7885 Tuning Knob Clip 7686 Pointer Drive Drum 8030 Range Switch Knob—Outer 5625 Main Drive Segment 8039 Volume-Battery-Tone Control Knob—Inner 4589 Main Drive Spindle Assembly 8035 Valve Sockets (4) 7929 Intermediate Drive Gear Assembly 8037 Valve Socket (Cushion) 7327 Dial Scale 8155 Valve Clips 8498 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 7251 | Drive Wire Jockey PulleysLarge | 6246 | Tuning Knob | . 8075 | |
| Pointer Drive Drum 8030 Range Switch Knob—Inner 4589 Main Drive Segment 8039 Volume-Battery-Tone Control Knob—Outer 5625 Main Drive Spindle Assembly 8035 Value Battery-Tone Control Knob—Inner 4589 Main Drive Spindle Assembly 8035 Value Sockets (4) 4704 Intermediate Drive Gear Assembly 8037 Valve Socket (Cushion) 7327 Dial Scale 8155 Valve Clips 7459 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 7251 | Drive Wire Jockey Pulleys-Small | . 7885 |
Tuning Knob Clip
Range Switch Knob—Outer |
. 768
6
. 56 2 5 |
|
| Main Drive Segment 8039 Volume-Battery-Tone Control Knob—Inner 4589 Main Drive Spindle Assembly 8035 Valve Sockets (4) 7029 Intermediate Drive Gear Assembly 8037 Valve Socket (Cushion) 7327 Dial Scale 8155 Valve Clips 8498 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 7251 | Pointer Drive Drum | 8030 |
Range Switch Knob—Inner
Volume-Battery-Tone Control Knob—Outer |
. 4589
. 5625 |
|
| Main Drive Spindle Assembly 8035 Knob Clips 7929 Main Drive Spindle Assembly 8035 Valve Sockets (4) 4704 Intermediate Drive Gear Assembly 8037 Valve Sockets (4) 7327 Dial Scale 8155 Valve Clips 7459 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 7251 | Main Drive Segment | 8039 | Volume-Battery-Tone Control Knob—Inner | 4589 | |
| Intermediate Drive Gear Assembly 8037 Valve Socket (Cushion) 7327 Dial Scale 8155 Valve Clips 8498 Dial Lamp Sockets 4195 Loudspeaker Cone AssemblyModel 190 7251 | Main Drive Spindle Assembly | 8035 |
Knob Clips
Valve Sockets (4) |
7929
4704 |
|
| Dial Scale 8155 Valve Clips 7459 Dial Lamp Sockets 4195 Loudspeaker Cone Assembly—Model 190 8588 | Intermediate Drive Gear Assembly | 8037 |
Valve Socket (Cushion)
Vibrator Socket |
8498 | |
| Dial Lamp Sockets | Dial Scale | 8155 |
Valve Clips
Loudspeaker Cone Assembly—Model 88 |
7459 | |
| Dial Lamp Sockets | 4195 | Loudspeaker Cone Assembly-Model 190 | 7251 | ||
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