3
72FF-57E
81FF-57E
IMPORTANT SERVICE NOTES
SERVICING OF HIGH VOLTAGE SYSTEM AND PICTURE TUBE
Maintenance and repair of this receiver should be done by qualified service personnel only.
When servicing the high voltage system, remove static charge from it by connecting a 10K ohm
resistor in series with an insulated wire (such as test probe) between picture tube ground tag and
high voltage lead. (AC line cord should be disconnected from AC outlet).
1. Picture tube this receiver employs Integral Implosion protection.
2. Replace with tube of the same type number for continued safety.
3. Do not lift picture tube by the neck.
4. Handle the picture tube only when wearing shatterproof goggles and after discharging the high
voltage completely.
X-RAY
This receiver is designed so that any X-Ray radiation is kept to an absolute minimum. Since certain
malfunctions are servicing may produce potentially hazardous radiation with prolonged exposure at
close range, the following precautions should be observed:
1. When repairing the circuit, be sure not to increase the high voltage to more than 32 KV, (at beam
1300
µΑ)
for the set.
2. To keep the set in a normal operation, be sure to make it function on 29KV
±
1KV (at beam 1300
µΑ)
in the case of the set. The set has been factory - adjusted to the above mentioned high voltage. If
there is a possibility that high voltage fluctuates as a result of the repairs, never forget to check for
such high voltage after the work.
3. Do not substitute a picture tube with unauthorized types and/or brands which may cause excess
X-Ray radiation.
BEFORE RETURNING THE RECEIVER
In addition to the checks necessary as a result of a repair having been carried out, the following
additional safety checks should also be made before returning the units to the user.
1. Inspect all lead dress to make certain that leads are not pinched or that hardware is not logged
between the chassis and other metal parts in the receiver.
2. Inspect all protective devices such as non-metallic control knobs, insulating fish papers, cabinet
backs, adjustment and compartment covers or shields, insolation resistor-capacity networks,
mechanical insulators etc.
Summary of Contents for 72FF-57E
Page 18: ...18 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 POWER SWITCH UNIT PRINTED WIRING BOARDS ...
Page 19: ...19 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 SOUND OUTPUT UNIT PRINTED WIRING BOARDS ...
Page 22: ...22 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 100Hz UNIT PRINTED WIRING BOARDS ...
Page 24: ...24 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 Page 25 MOTHER UNIT 1 SCHEMATIC DIAGRAM ...
Page 34: ...34 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 POWER SWITCH UNIT SCHEMATIC DIAGRAM ...
Page 35: ...35 72FF 57E 81FF 57E FRONT A V UNIT SCHEMATIC DIAGRAM 1 I H G F E D C B A 2 3 4 5 6 7 ...
Page 36: ...36 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 Page 37 SCART UNIT SCHEMATIC DIAGRAM ...
Page 38: ...38 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 Page 39 100Hz UNIT SCHEMATIC DIAGRAM ...
Page 40: ...40 72FF 57E 81FF 57E SOUND OUTPUT UNIT SCHEMATIC DIAGRAM 1 I H G F E D C B A 2 3 4 5 6 7 9 8 ...
Page 41: ...41 72FF 57E 81FF 57E 72FF 57E BLOCK DIAGRAM 1 I H G F E D C B A 2 3 4 5 6 7 ...
Page 42: ...42 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 81FF 57E BLOCK DIAGRAM Page 43 ...
Page 43: ...43 72FF 57E 81FF 57E 8 9 10 11 12 13 14 I H G F E D C B A 81FF 57E BLOCK DIAGRAM Page 42 ...
Page 44: ...44 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 PWBs LAYOUT ...
Page 45: ...45 72FF 57E 81FF 57E 1 I H G F E D C B A 2 3 4 5 6 7 SCHEMATIC DIAGRAMS CONECTION ...
Page 59: ...59 72FF 57E 81FF 57E NOTES ...
