614-T & 711-C
TECHNICAL INFORMATION AND SERVICE DATA
Models 614-T & 711-C
FIVE VALVE, FIVE BAND, A.C. OPERATED SUPERHETERODYNES
ISSUED BY
AMALGAMATED WIRELESS (A/SIA.) LTD.
ELECTRICAL SPECIFICATIONS.
| FREQUENCY RANGES: 1600-540 Kc/s (187.5-555 M.) 4-1.5 Mc/s (75-200 M.) 10-3.7 Mc/s (30-81 M.) 15-9.5 Mc/s (20-31.5 M.) 23-14.7 Mc/s (13-20.4 M.) | UNDISTORTED POWER OUTPUT: | 4.5 watts. |
|---|---|---|
| INTERMEDIATE FREQUENCY 455 Kc/s | CONTROLS: | |
|
POWER SUPPLY RATING 200-260 volts, 50-60 C.P.S.
(Models are produced with other voltage and frequency ratings.) |
||
| POWER CONSUMPTION | TUNING | |
| DIAL LAMPS (3) | ||
|
VALVE COMPLEMENT:
(1) 6J8G Converter. (2) 6SK7GT I.F. Amplifier. (3) 6SQ7GT Detector, A.V.C., and A.F. Amplifier. (4) 6V6GT/G Output. (5) SY3GT/G Rectifier. |
||
|
LOUDSPEAKER:
Model 614-T. 7 inch—Code No. AW4. Transformer—XA1. V.C. Impedance—3 ohms at 400 C.P.S. Field—1500 ohms. Field—1500 ohms. LQ E 2 Model 711-C. 12 inch—Code No. AS8 or AS13 Transformer—IX20. V.C. Impedance—2.2 ohms at 400 C.P.S. Field—1500 ohms. |
OFF ON SOFT DLOUD D
POWER VOLUME PHONO-RANGE |
TONE |
|
MECHANICAL SPEC
Height. Width. Depth. |
IFICATIONS.
Height. Width |
. Depth. |
| Height. | Width. | Depth. | Height. Width. | Depth | |
|---|---|---|---|---|---|
| Cabinet Dimensions (inches)- | - | Chassis Base Dimensions (inches) 27 127 | 678 | ||
| 614-T | . 12 | 23 | 10 5/16 | Weight (nett Ibs.)— | |
| 711-C | . 32 1 | 323 | 13 | 614-T | . 35 |
| Carton Dimensions (inches)— | 711-C | 85 | |||
| 614-1 | . 13 1 | 24 | 12 | 00 | |
| 711-C |
. 33
|
34 | 141 | Cabinet Finish Walnut Ve | neer |
CIRCUIT DIAGRAM AND CODE
|
Circuit
Code No. |
Stock Code
Description. or Part No. |
Circuit Stock Code
Code No. Description. or Part No. |
Circuit Stock Code
Code No. Description. or Part No |
|---|---|---|---|
|
L1, 2
L3, 4 L5, 6 L7, 8 L9, 10 L11, 12 L13, 14 L15, 16 L17, 18 L19, 20 L21 R1 R2 R3 R4 R5 R6 R7 R8 R9 P12 |
INDUCTORS. Aerial Coil, 1600-540 kc. 9748 Aerial Coil, 4-1.5 Mc. and 10-3.7 Mc. 9854 Aerial Coil, 15-9.5 Mc. and 23-14.7 Mc. 20442 Oscillator Coil, 23-14.7 Mc. 20441 Oscillator Coil, 15-9.5 Mc. Mc. 20441 Oscillator Coil, 15-9.5 Mc. Mc. 20441 Oscillator Coil, 15-9.5 Mc. Mc. 20441 Oscillator Coil, 15-9.5 Mc. Mc. 20440 Oscillator Coil, 15-9.5 Mc. Mc. 20440 Oscillator Coil, 160-540 kc. 9741 kc. 9741 Ist I.F. Transformer 20443 2nd I.F. Transformer 8287Z Speaker field, 1500 ohms RESISTORS. 32,000 ohms, ½ watt 1 megohm, ½ watt 20,000 ohms, 1 watt Not used 20,000 ohms, ½ watt 1.6 megohms, ½ watt 1.6 megohms, ½ watt 1.6 megohms, ½ watt | R15 2.5 megohms, ½ watt R16 40 ohms, 3 watt R17 0.25 megohm, 1 watt R18 20,000 ohms, 1 watt R19 0.5 megohm, ½ watt R20 250 ohms, 3 watt R21 0.1 megohm, Tone Control R22 50,000 ohms, ½ watt CAPACITORS. C1 2-25 uuF air trimmer C2 2-25 uuF air trimmer C3 -225 uuF air trimmer C4 12-430 uuF variable (ganged) C5 120 uuF N750 Temp. Comp. ±2½% C6 C10 120 uuF mica padder (1600-540 kc.) ± 2½% C10 120 uuF variable (ganged) C12 2-25 uuF air trimmer C9 490 uuF mica padder (1600-540 kc.) ± 2½% C10 120 uuF variable (ganged) C12 2-25 uuF air trimmer C13 1350 uuF mica padder (4-1.5 Mc.) ± 2½% C14 2-25 uuF air trimmer C15 12 uuF mica C16 2500 uuF mica padder (10.37 Mc.) ± 2½% |
C20
.01 uF paper, 600 v.
working C21 70 uuF mica C22 70 uuF mica C23 .02 uF paper, 600 v. working C24 12 uuF mica C25 .1 uF paper, 400 v. working C26 .01 uF paper, 600 v. working C27 70 uuF mica C28 70 uuF mica C29 100 uuF mica C30 100 uuF mica C31 .02 uF paper C33 .01 uF paper, 400 v. working C34 200 uuF mica C33 .01 uF paper, 400 v. working C34 200 uuF mica C35 .5 uF paper, 400 v. working C36 .1 uF paper, 400 v. working C37 16 uF, 525 P.V. Electrolytic C38 25 uF, 40 P.V. Electrolytic C38 25 uF, 400 v. working C40 8 uF, 525 P.V. Electrolytic C41 0.5 uF paper, 400 v. working C42 0.005 uF paper, 600 v. working TRANSFORMERS. T1 Power Transformer, 50-60 C.P.S. 11344 T1 Power |
|
R12
R10 R11 R13 R14 |
25,000 ohms, 2 watt
25,000 ohms, 2 watt 20,000 ohms, 1 watt 0.5 megohm, Volume Control 10 megohms, 1 watt |
C17 2-25 uF air trimmer
C18 05 uF paper, 200 v. working C19 50 uuF mica |
LOUDSPEAKER. 7 inch Electro Magnet AW4 12 inch Electro Magnet ASI3 |
D.C. RESISTANCE OF WINDINGS
| Winding. | D.C. Resistance in ohms. |
|---|---|
| Aerial Coils— | |
| Primary (LI) | 13 |
| Secondary (L2) | 4 |
| Primary (L3) | 3.5 |
| Secondary (L4) | 2 |
| Primary (L5) | 2.5 |
| Secondary (L6) | .5 |
| Oscillator Coils— | |
| Primary (L7) | .5 |
| Secondary (L8) | * |
| Primary (L9) | .5 |
| Secondary (LIO) | * |
| Primary (LII) | .5 |
| Secondary (L12) | * |
| Primary (L13) | .5 |
| Secondary (L14) | 1.5 |
| Primary (L15) | 1.75 |
| Secondary (L16) | 7 |
| I.F. Transformer Windings | 8 |
| Power Transformer T2— | |
| Primary | 16 |
| Secondary | 520 |
| Loudspeaker Input | |
| Transformer— | |
| Primary, XAI | 500 |
| Secondary, XAI | * |
| Primary, TX20 | 420 |
| Secondary, TX20 | * |
The above readings were taken on a standard chassis, but substitution of materials during manufacture may cause variations, and it should not be assumed that a component is faulty if a slightly different reading is obtained. * Less than 1 ohm.
| Valves. |
Control Grid
to Chassis Volts. |
Cathode to
Chassis Volts. |
Screen Grid
to Chassis Volts. |
Plate to
Chassis Volts. |
Plate
Current mA. |
Heater
Volts. |
|---|---|---|---|---|---|---|
| 6J8G Converter | . –2.6 | 0 | 85 | 260 | 1.3 | 6.3 |
| Oscillator | . — | en e | 150 | 5.0 | ||
| 6SK7GT I.F. Amplifier | 2.6 | 0 | 85 | 260 | 6.5 | 6.3 |
|
6SQ7GT Detector, A.V.C. and A.F
Amplifier |
0 | 0 | 100* | 0.6 |
*
6.3 |
|
| 6V6GT/G Output | . 0 | 12.5 | 260 | 240 | 45 | 6.3 |
| 5Y3GT/G Rectifier | . 770/385 vo | olts, 70 mA to | otal current. |
SOCKET VOLTAGES
* This reading may vary depending on the resistance of the voltmeter used.
Measurements taken with the receiver connected to 240 volts A.C. supply. Range switch at "Broadcast" and no signal input. Volume control maximum clockwise. Voltmeter, 1000 ohms per volt; measurements taken on highest scale giving accurate readable deflection.
MECHANICAL REPLACEMENT PARTS.
| Item. | Part No. | ltem. | Part No |
|---|---|---|---|
| Cabinet, console | C69Z | Dust Cover, loudspeaker- | |
| Cabinet, table | C77 |
-
AW4 |
9843 |
| Cable, loudspeaker— | AS8 | 10306 | |
| Table | 17822 | AS13 | 10306 |
| Console | 6465 | Knob | 4589 |
| Cable, power | 209 | Knob, tuning | 9 407 |
| Cable, tone control— | Screen, I.F. transformer | 3351 | |
| Table | 20432 | Сар | 8372 |
| Console | 20431 | Socket, valve | 4704 |
| Clip, grid | 7459 | Socket, valve, cushion | 20142 |
| Cone, assembly, loudspeaker | Spindle, tuning control extension- | ||
| Түре АW4 | 9356 | Table | 19066 |
| Type AS8 | 7071 | Console | 19583 |
| Type ASI3 | 7071 | Spring, drive tension | 1741 |
| Type 7.313 | 1011 | Strip, tag, I way | 7628 |
| Dial frame assembly | 20501A | 5 way | 8239 |
| Dial Scale | 20500A | 7 way | 9879 |
| Drum, band indicator | 20544 | Washer, felt | 4935 |
ALIGNMENT PROCEDURE.
Alignment should be necessary only 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 given in this booklet, and to use adequate and reliable test equipment. Instruments ideally suited to the requirements are either the A.W.A. Junior Signal Generator type 2R3911, or the A.W.A. Modulated Oscillators type J6726 and C1070*. An output meter is necessary with both these instruments, the recommended type having an output impedance of 5000 ohms and a range of 5-3000 milliwatts. The meter should be connected across the primary of the loudspeaker transformer. If the output meter used is one which impresses a load on the anode circuit of the output valve, it will be necessary to open the voice coil if true power indications are required.
As the calibration of the band-spread bands requires great accuracy, it is recommended that an A.W.A. Crystal Calibrator, type 6795, be used to check the accuracy of the signal generator. The crystal calibrator emits a modulated signal at intervals of either 100 or 1000 Kc/s, throughout the radio frequency spectrum, thus providing a series of fixed and equally spaced calibration points of known accuracy. When using this instrument care should be taken to select the correct signal. With the crystal set at the 1000 Kc. position a spurious image signal can aenerally be obtained by turning the tuning control of the receiver to a point approximately 100 Kc/s higher in freauency. This is a useful check as to whether a harmonic or spurious image is being tuned. If a crystal calibrator is not available, broadcasting stations of known frequency may be used as an alternative.
When using a signal generator or modulated oscillator with the tuning of the receiver fixed, two frequencies can be tuned from the test instrument, one 0.92 Mc/s higher in frequency than the other. In all cases the desired frequency is the lower of the two.
A convenient alignment jig designed to hold the receiver chassis and fitted with a dial scale and pointer may be obtained from the Service Department of the company. With this jig, alignment may be carried out with the chassis coupled to an actual scale, thus ensuring that the calibration will be correct when the chassis is placed in the cabinet, otherwise, use the 0-180° calibration scale on the drum. (See alignment table.)
For all alignment purposes connect the "low" side of the signal generator to the receiver chassis.
Perform alignment in the proper order as shown in the chart, starting from No. I and following all operations across, then No. 2, etc.
Keep the volume control 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 cellulose cement.
* If a type J6726 or C1070 instrument is used, see that a 0.25 megohm resistor is connected between the output terminals, and for short wave alignment a 400 ohm non-inductive receiver in series with the active output lead.
|
Align
ment Order |
• Test Inst.
Connect to . Receiver. |
Frequency
Setting. |
Band
Setting. |
Calibration
Scale Setting. |
Circuit to
Adjust. |
Adjustment
Symbol. |
Adjust to
Obtain. |
|---|---|---|---|---|---|---|---|
| 1 | 6J8G Cap.* | 455 Kc/s | Broadcast | 0° | 2nd L.E. Transformer | Core L20 | Max. Peak |
| 2 | 6J8G Cap.* | 455 Kc/s | Broadcast | 0° | 2nd LE Transformer | Core L19 | Max. Peak |
| 3 | 6J8G Cap.* | 455 Kc/s | Broadcast | 0° | Ist IF Transformer | Core 118 | Max Peak |
| 4 | 6J8G Cap.* | 455 Kc/s | Broadcast | 0° | Ist I.F. Transformer | Core LI7 | Max. Peak |
| Recheck | I. 2. 3 and 4 | 4. | , | ||||
| 5 | I Aerial | 1 600 Kc/s 1 | Broadcast | 1 20° | I Oscillator† | L Core 115 | Max Peak |
| 6 | Aerial | 1500 Kc/s | Broadcast | 155° | Oscillator | CI7 | Calibration |
| . 7 | Aerial | 1500 Kc/s | Broadcast | 155° | Aerial | CI | Max. Peak |
| • | 2 🖷 | • | • | ||||
| Reche | eck 5, 6, 7. | ||||||
| 8 | J Aerial | | 1.6 Mc/s ] |
Reche
4-1.5 Mc/s |
eck 5, 6, 7.
I 16° |
| Oscillator† | | Core LI3 | Max. Peak |
| 8 |
Aerial
Aerial |
1.6 Mc/s
3.6 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s |
eck 5, 6, 7. |
Oscillator†
Oscillator |
Core LI3
CI4 |
Max. Peak
Calibration |
|
8
9 10 |
Aerial
Aerial Aerial |
1.6 Mc/s
3.6 Mc/s 3.6 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s |
eck 5, 6, 7.
| 16° | 147° | 147° |
Oscillator†
Oscillator Aerial |
Core LI3
CI4 C2 |
Max. Peak
Calibration Max. Peak |
|
8
9 10 11 |
Aerial
Aerial Aerial Aerial |
1.6 Mc/s
3.6 Mc/s 3.6 Mc/s 4.0 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s 10-3.7 Mc/s |
eck 5, 6, 7.
16° 147° 147° 18° |
Oscillator†
Oscillator Aerial Oscillator† |
Core LI3
CI4 C2 Core LI1 |
Max. Peak
Calibration Max. Peak Max. Peak |
|
8
9 10 11 12 |
Aerial
Aerial Aerial Aerial Aerial |
1.6 Mc/s
3.6 Mc/s 3.6 Mc/s 4.0 Mc/s 9.5 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s 10-3.7 Mc/s 10-3.7 Mc/s |
eck 5, 6, 7.
16° 147° 147° 18° . 160° |
Oscillator†
Oscillator Aerial Oscillator† Oscillator |
Core LI3
CI4 C2 Core LI1 CI2 |
Max. Peak
Calibration Max. Peak Max. Peak Calibration |
|
8
9 10 11 12 13 |
Aerial
Aerial Aerial Aerial Aerial Aerial |
1.6 Mc/s
3.6 Mc/s 3.6 Mc/s 4.0 Mc/s 9.5 Mc/s 9.7 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s 10-3.7 Mc/s 10-3.7 Mc/s 15-9.5 Mc/s |
eck 5, 6, 7.
16° 147° 147° 18° . 160° 21° |
Oscillator†
Oscillator Aerial Oscillator† Oscillator Oscillator |
Core LI3
CI4 C2 Core LI1 CI2 Core L9 |
Max. Peak
Calibration Max. Peak Max. Peak Calibration Calibration |
|
8
9 10 11 12 13 14 |
Aerial
Aerial Aerial Aerial Aerial Aerial Aerial |
1.6 Mc/s
3.6 Mc/s 3.6 Mc/s 4.0 Mc/s 9.5 Mc/s 9.7 Mc/s 14.0 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s 10-3.7 Mc/s 10-3.7 Mc/s 15-9.5 Mc/s 15-9.5 Mc/s |
eck 5, 6, 7.
16° 147° 147° 18° . 160° 21° 153° |
Oscillator†
Oscillator Aerial Oscillator† Oscillator Oscillator Oscillator |
Core LI3
CI4 C2 Core LI1 CI2 Core L9 C8 |
Max. Peak
Calibration Max. Peak Max. Peak Calibration Calibration Calibration |
|
8
9 10 11 12 13 14 15 |
Aerial
Aerial Aerial Aerial Aerial Aerial Aerial Aerial |
1.6 Mc/s 3.6 Mc/s 3.6 Mc/s 4.0 Mc/s 9.5 Mc/s 9.7 Mc/s 14.0 Mc/s 14.0 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s 10-3.7 Mc/s 10-3.7 Mc/s 15-9.5 Mc/s 15-9.5 Mc/s 15-9.5 Mc/s |
eck 5, 6, 7.
16° 147° 147° 18° 160° 21° 153° 153° |
Oscillator†
Oscillator Aerial Oscillator† Oscillator Oscillator Oscillator Aerial |
Core LI3
CI4 C2 Core LI1 CI2 Core L9 C8 C3 |
Max. Peak
Calibration Max. Peak Max. Peak Calibration Calibration Calibration Max. Peak |
|
8
9 10 11 12 13 14 15 16 |
Aerial
Aerial Aerial Aerial Aerial Aerial Aerial Aerial Aerial |
1.6 Mc/s 3.6 Mc/s 3.6 Mc/s 4.0 Mc/s 9.5 Mc/s 14.0 Mc/s 14.0 Mc/s 15.0 Mc/s |
Reche
4-1.5 Mc/s 4-1.5 Mc/s 4-1.5 Mc/s 10-3.7 Mc/s 10-3.7 Mc/s 15-9.5 Mc/s 15-9.5 Mc/s 15-9.5 Mc/s 23-14.7 Mc/s |
eck 5, 6, 7.
16° 147° 147° 18° 160° 21° 153° 153° 19° |
Oscillator†
Oscillator Aerial Oscillator† Oscillator Oscillator Oscillator Aerial Oscillator |
Core LI3
CI4 C2 Core LI1 CI2 Core L9 C8 C3 Core L7 |
Max. Peak
Calibration Max. Peak Max. Peak Calibration Calibration Calibration Max. Peak Calibration |
ALIGNMENT TABLE.
* With Grid Clip connected. A 0.001 uF capacitor should be connected in series with the "High" side of the test instrument. † Rock the tuning control back and forth through the signal.
The column headed "Calibration Scale Setting" refers to the 180° scale on the ganged tuning capacitor drum drive. Check the setting of the drum before taking readings. The zero mark should be opposite the pointer with the tuning capacitor fully closed.
CONNECTION TO POWER SUPPLY.
The receiver should not be connected to any circuit supplying other than alternating current from 200 to 260 volts and at the frequency stated on the label within the cabinet. The power supply connection panel is shown in the accompanying diagram, and for 230 to 260 volt operation the input leads from the power switch (S2) should be connected to tags B and G. For operation on voltages below 230, connection should be made to tags B and W.
BLUE -GREEN
SERVICE WINDOW.
A "Service Window" is provided in the base of the table model cabinet. The window is covered by a perforated grille fastened by four knurled nuts. With the grille removed, it is possible to perform most service operations without removing the chassis from the cabinet.
TUNING DRIVE CORD REPLACEMENT.
The accompanying diagram shows the route of the cord and the method of attachment. Whilst fitting the cord, keep it taut and adjust the length so that the tension spring measures approximately 2 inches long when fitted. The spring should be sheathed to prevent it rattling against the drum.
DESCRIPTION OF TUNING CIRCUIT ADJUSTMENTS
BROADCAST BAND.
The broadcast band adjustments follows usual practice with two trimming capacitors—CI aerial, CI7 oscillator and a variable magnetite core for L.F. adjustment of the oscillator coil L15, L16.
4-1.5 Mc/s Band.
Adjustments are similar to those used on the broadcast band, that is, with two trimming capacitors, C2 aerial, CI4 oscillator and a variable magnetite core for L.F. adjustment of the oscillator coil LI3, LI4.
10-3.7 Mc/s Band.
The capacitor in the aerial section is common with that in the 4-1.5 Mc/s band, the change of band being accomplished by switching tapped coils. The oscillator section, however, is provided with a separate capacitor, C12, for tracking with the signal circuits at the H.F. end and a variable magnetite core for L.F. adjustment of the oscillator coil L11, L12.
15-9.5 Mc/s Band.
Adjustments are the same as used on 4-1.5 Mc/s band, that is, with two trimming capacitors, C3 aerial, C8 oscillator and a variable magnetite core for L.F. adjustment of the oscillator coil L9, L10.
23-14.7 Mc/s Band.
One adjustment only is provided, a variable magnetite core in the oscillator coil L7, L8.
It will be noted that the ratio max. frequency min. frequency is the same on the 2 bands, 15-9.5 Mc/s, 23-14.7 Mc/s, and the tracking is correct using the same series capacitor for both bands. The ratio max. frequency min. frequency same on the 4.0-1.5 Mc/s and 10-3.7 Mc/s bands, but, due to the greatly different frequency spectrum of the oscillator, the series capacitors in the two oscillator circuits are different.
CHASSIS (UNDERNEATH VIEW).
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