The cabinet style of these models is as follows:—Models 85 & 91, Table; Models 195 and 200, Console; Model 312, Radio-Gramophone Combination. The latter is of revolutionary design, the lower section of the cabinet withdraws, revealing the gramophone turntable and pick-up. When closed, the gramophone section is entirely console.
As is the case with all other models released in the 1940 range, one of the most striking features is the unique chassis layout. In these receivers the valves are most accessible, as they are arranged
in line at the rear of the chassis in the same sequence as they appear on the circuit diagram. By careful placement of other components, efficiency has been increased, crowding has been eliminated, and a big improvement has resulted both in performance and from a servicing aspect.
A feature of the Models 85, 195 and 312 is the dual ratio tuning drive. This drive has two ratios; one, 2½ to 1, providing a quick shift to any position on the dial, and the other, 58 to 1, providing vernier tuning for one revolution of the knob.
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
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. ment, a 400 ohms non-inductive resistor in series with the active
Connect the around connection of the test instrument to the
Perform alignment in the proper order, starting from No. I and tollowing all operations across, then No. 2, etc. Adjustment loca-
tions 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 cenent to eliminate the possibility of them shifting and also to indicate whether they
ADJUSTING TOOLS.
Two tools, which have been specially designed for alignment pur-poses, 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.
|
Alignment
Order. |
Test Inst. Connection
to Receiver. |
Test. Inst.
Setting. |
Receiver Dial
Setting. |
Circuit to
Adjust. |
Adjustment
Symbol. |
Adjust to
Obtain |
|---|---|---|---|---|---|---|
| I | *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s.†† | 2nd I.F. Trans. | L12 | Max. (Peak) |
| 2 | *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s .† † | 2nd I.F. Trans. | LII | Max. (Peak) |
| 3 | *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s .†† | Ist I.F. Trans. | LIO | Max. (Peak) |
| 4 | *6J8G Grid Cap | 455 Kc/s. | Past 550 Kc/s .† † | Ist I.F. Trans. | L9 | Max. (Peak) |
| Repeat the | above adjustments be | fore proceeding. | ||||
| 5 | Aerial Term | 600 Kc/s. | 600 Kc/s.† | Oscillator | Core L6 | Max. (Peak) |
| 6 | Aerial Term | 1500 Kc/s. | 1500 Kc/s. | Oscillator | C6 | Max. (Peak) |
| 7 | Aerial Term | 1500 Kc/s. | 1500 Kc/s. | Aerial | C2 | Max. (Peak) |
| Rep | eat adjustments 5, 6, | and 7. | ||||
| 8 | Aerial Term | 15M. | 15M. | Oscillator | C8 | Max. (Peak)** |
| 9 | Aerial Term | 15M. | 15M.‡ | Aerial | C3 | Max. (Peak)*** |
ALIGNMENT TABLE
* With grid clip connected. A .001 mfd. condenser should be connected in series with the active output lead of the test
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.
SOCKET VOLTAGES.
| VALVE |
Bias
Volts |
Screen
Grid to Chassis Volts |
Plate to
Chassis Volts |
Plate
Curren M.A. |
t Heater
Volts |
||
| 6J8G Converter M.W | -3* | 95 | 255 | 1.3 | 6.3 | ||
| S.W | -3 | 95 | 255 | 1.3 | |||
| Oscillator M.W | — | 160 | 5.0 | ||||
| S.W | 160 | 5.0 | |||||
| 6U7G I.F. Amplifier M.W | -3* | 95 | 255 | 8.0 | 6.3 | ||
| S.W. | -3* | 95 | 255 | 8.0 | — | ||
| 6B6G 2nd Detector | 0 | 125* | 0.52 | 6.3 | |||
| 6V6G Output | -12.5* | ° 255 | 242 | 44.0 | 6.3 | ||
| 5Y3G Rectifier 800/400 volt | ts, 75 | M.A. | Total ci | urrent, | 5.0. | ||
*Cannot be measured with ordinary voltmeter.
Measured at 240 volts. A.C. supply. No signal input. Volume Control at maximum.
GRAMOPHONE MOTOR AUTOMATIC STOP ADJUSTMENT (MODEL 312).
Two types of motors are used in this Receiver, namely "Collaro" and "Garrard," and as the adjustment is different for each, first identify the motor in question before proceeding. The trade marks for the "Collaro" and "Garrard" are on the motor board and pick-up, respectively.
"COLLARO" ADJUSTMENT.
The Automatic stop is set at the factory to suit standard records. If adjustment becomes necessary, loosen the stop adjustment screws and adjust the trip lever so that the pick-up arm comes in contact with the lever when the needle enters the continuous track outside the record label.
"GARRARD" ADJUSTMENT.
The Patent Stop and Switch is fully automatic.
As the needle travels towards the centre of the record, the Pickup Arm moves Friction Plate A (see diagram) which, through the friction pad and spring, carries with it the Main Lever B and Trip Lever C.
This Main Lever moves in towards the Turntable Spindle on which is mounted the striker, which gently wipes against the rubber bush on end of Trip Lever C at every revolution, thus tapping back the Main Lever B (the friction between Lever A and Lever B allows this).
The "tapping back" process continues until the needle reaches the "run-in" groove in the centre of the record. The trip lever is now moved forward into the path of the striker, which strikes the side of the lever and trips the Stop mechanism.
If Stop fails to operate at finish of record, there is probably insufficient friction between Lever A and Lever B. This may be rectified by turning the friction screw in lever B in a counterclockwise direction.
When Stop operates early, i.e., before needle reaches the end of the record, the trouble is either due to excessive friction or to the rubber bush on the trip lever being worn. Friction can be reduced by turning the friction screw clockwise.
As this adjustment is very sensitive, the screw should not be turned more than a quarter of a turn at a time. Excessive friction may cause a knocking sound to be heard in the loudspeaker and undue wear on records.
When the rubber bush is worn, this may be turned round on its pin to expose a new face to the striker.
A brake pad is provided which is automatically applied to the turntable rim after switching off. It can be adjusted by loosening the two screws securing the brake pad lever. After adjustment, it is important to verify that the switch breaks contact before brake operates.
"Garrard" Automatic Stop Mechanism.
MECHANICAL REPLACEMENT PARTS
| TUNING MECHANISM. | MISCELLANEOUS. | |||
|---|---|---|---|---|
| DESCRIPTION | Part No. | DESCRIPTION | Part No | |
| Pointer and Saddle, with Drive Wire | 6629 | Range Switch85, 91, 195 and 200 | 7907 | |
| Drive Wire Tension Spring | 6641 | Range Switch—312 | 8109 | |
| 6246 | Power Cable | 209 | ||
| Drive wire Jockey Fulleys-Large | Loudspeaker Cable | 6465 | ||
| Drive Wire Jockey Pulleys-Small | 7885 | Tuning Knob | 8075 | |
| Pointer Drive Drum | 8030 | Tuning Knob Clip | 7686 | |
| Main Drive Segment | 8039 | Range Switch Knob—Outer | 5625 | |
| 0005 | Range Switch Knob—Inner | 4589 | ||
| Main Drive Spindle Assembly | 8035 | Volume-Tone Control Knob—Outer | 5625 | |
| Intermediate Drive Gear Assembly | 8037 | Volume-Tone Control Knob—Inner | 4589 | |
| Dial Scale | 8154 | Knob Clips | 7929 | |
| 4104 | Valve Sockets (4) | 4704 | ||
| Dial Lamp Sockets | Valve Socket (Cushion) | 7327 | ||
| Valve Clips | 7459 | |||
Loudspeaker Cone Assembly—Models 85 and 91 ...... 8588 Loudspeaker Cone Assembly—Models 195, 200 and 312 .... 7071
NOTE:-Pick-up terminals, shown in the circuit diagram, are not provided in the Models 91 and 200.
COILS. L1, L2 7974 Aerial Coil 1600-550 K.C. L3, L4 7975 Aerial Coil 13.6-45M L5, L6 9145 Osc. Coil 1600-550 K.C. L7, L8 9145 Osc. Coil 13.6-45M L9, L10 8286 1st I.F. Transformer L11, L12 8287 2nd I.F. Transformer NOTE. Prior to 1-5-40 oscillator coil, No. 7977 was used TRANSFORMERS. TI 7979A Power Transformer 50-ТΙ 7981A Power Transformer 40C Т2 XAI Loudspeaker Transfor-mer (85, 91) TX20 Loudspeaker Tr mer (195, 200 Т2 Code Part No. No. RESISTORS. RI 50.000 ohms 1/3W R2 350 ohms 1/3W R3 8000 ohms 1W R4 6000 ohms 2W 100,000 ohms 1/3W R6 1.75 megohms 1/3W
20.000 ohms 1W
R7
| R8 | 50,000 ohms 1/3W | C12 | 70 mmfd mica (N) | ||
|---|---|---|---|---|---|
| R9 | 7903 | 500,000 ohms Vol. Cont. | C13 | 7985 | Tuning Condenser |
| R10 | 10 megohms IW | C14 | 70 mmfd mica (N) | ||
| RH | 250 ohms 3W | C15 | 70 mmfd mica (N) | ||
| R12 | 50,000 ohms 1/3W | C16 | .01 mfd paper | ||
| R13 | 500,000 ohms 1/3W | C17 | .1 mfd paper | ||
| R14 | 250,000 ohmas 1W | C18 | .1 mfd paper | ||
| R15 | 1.75 me gohms IW | C19 |
16 mfd, 500V. electrolyti
|
||
| R16 | 7902 | 100,000 ohms Tone Cont. | C20 | 4 mmfd mica | |
| R17 | 20,000 ohms 1W | C21 | 70 mmfd mica (N) | ||
| R18 | 40 ohms 3W | C22 | 70 mmfd mica (N) | ||
| R19 | 2.3 megohms 1/3W | C23 | 110 mmfd mica (L) | ||
| Code | Part | C24 | 110 mmfd mica (L) | ||
| No. | No. | CONDENSERS. | C25 | .01 mfd paper | |
| ĊI | 4 mmfd mica | C26 | 16 mfd 350V. regulating elec | ||
| C2 | 3661 | 2-20 mmfd air trimmer | trolytic | ||
| C3 | 3661 | 2-20 mmfd air trimmer | C27 | 50 mmtd mica (D) | |
| C4 | 7985 | Tuning Condenser | C28 | 25 mfd 25V. electrolytic | |
| C5 | .05 mfd paper | C29 | .02 mfd paper | ||
| C6 | 3411A | 11-29 mmfd air trimmer | C30 |
.0025 mfd paper (195, 200)
.015 mfd paper (85, 91) |
|
| C7 | 440 mmfd mica (padder) | C31 | 200 mmfd mica (J) | ||
| C8 | 3658 | 2-10 mmfd air trimmer | C32 | .1 mfd paper | |
| C9 | 4000 mmfd mica (padder) | C33 | .5 mfd paper | ||
| C10 | .05 mfd paper | ||||
| сп | .05 mfd paper | ||||
CIRCUIT DIAGRAM AND CODE-MODEL 312
NOTE:--Condenser C1 is incorrectly shown. It should be connected between the aerial terminal and the control grid of the 6J8G, as in the Circuit Diagram overleaf.
| Code | Part | R9 | 50,000 ohms 1/3W | C10 | 4000 mmfd mica (padder) |
| No. | No. COILS. | RIO 7903 | 500,000 ohms Vol. Cont. | C11 | .05 mfd paper |
| LI, L2 | 7974 Aerial Coil 1600-550 K.C. | RH | 10 megohms IW | C12 | 70 mmfd mica (N) |
| L3, L4 | 7975 Aerial Coil 13.6-45M | R12 | 250 ohms 3W | C13 7985 | Tuning Condenser |
| L5, L6 | 9145 Osc. Coil 1600-550 K.C. | R13 | 50,000 ohms 1/3W | C14 | 70 mmfd mica (N) |
| L7, L8 | 9145 Osc. Coil 13.6-45M | R14 | 500.000 ohms 1/3W | C15 | 70 mmfd mica (N) |
| L9, L10 | 8286 Ist I.F. Transformer | RIS | 250.000 obms 1W | C16 | 4 mmfd mica |
| L11, L12 | 8287 2nd I.F. Transformer | RIA | C17 | .01 mfd paper | |
|
NOTE: Prior to 1-5-40 oscillator coil, No.
7977 was used. |
C18 | l mfd naper | |||
| 1.75 megonins I w | C19 | 16 mfd 500V electro | |||
| TRANSFORMERS. | R18 7902 | 100,000 ohms Tone Cont. | C20 | 70 mmfd mica (N) | |
| TI |
7979A Power Transformer 50-
60C |
R19 | 40 ohms 3W | 620 | |
| R20 | 50,000 ohms 1/3W | C21 | /o minid mica (N) | ||
| ΤI | 7981A Power Transformer 40C | R21 | 20,000 ohms 1/3W | C22 | 110 mmfd mica (L) |
| Т2 | TX20 Loudspeaker Transfor- | C23 | 110 mmfd mica (L) | ||
| mer | Code Part | C24 | .01 mfd paper | ||
| No. No. | CONDENSERS. | C25 | 50 mmfd mica (D) | ||
| No. No. | RESISTORS. | CI | 4 mmfd mica | C26 | 16 mfd 350V. Reg. Electro. |
| RI | 350 ohms 1/3W | C2 3661 | 2-20 mmfd air trimmer | C27 | .02 mfd paper |
| R2 | 50,000 ohms 1/3W | C3 3661 | 2-20 mmfd air trimmer | C28 | 25 mfd 25V. electrolytic |
| R3 | 20,000 ohms 1W | C4 7985 | Tuning Condenser | C29 | .0025 mfd paper |
| R4 | 8000 ohms 1W | C5 | .05 mfd paper | C30 | .1 mfd paper |
| R5 | 6000 ohms 2W | C6 3411A | 11-29 mmfd air trimmer | C31 | .5 mfd paper |
| R6 | 100,000 ohms 1/3W | C7 | .05 mfd paper | C32 | 200 mmfd mica (J) |
| R7 | 1.75 megohms 1/3W | C8 3658 | 2-10 mmfd air trimmer | C33 | .1 mfd paper |
| R8 | 2.3 megohms 1/3W | C9 | 440 mmfd mica (padder) | C34 | .01 mfd paper |
Layout Diagram—Models 85, 91, 195 and 200 (Underneath View).
Layout Diagram-Model 312 (Underneath View)
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