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SECONDARY VOLTAGES
The energy exchange caused at the primary induces several secondary voltages.
Pin 16/17 via DP051, CP051: two voltages, +UH and -UH, to supply power to the display
filament.
Pin 10 via RP056, DP056, CP057: a 33VE voltage used to obtain the Varicap voltage for the
tuner.
Pin 18 via RP053, DP053, CP054, stabilised by DP054: -30 V for the display grid, and then
stabilised by DW010: a -5VE voltage used to power the switching stages.
Pin 18 via DP081, DP082, CP081, CP082: a +36VE voltage used for the POWER GOOD
function.
Pin 11 via DP061, CP061: a +20VE VM voltage used to over-supply the capstan motor for the
REWIND function.
Pin 15 via DP064, CP064, LP064, CP065: a 14 VE voltage. This voltage is used to obtain
three voltages to supply power to the motors:
-13.6 VEDM for the drum motor,
-13 VELM for the function control motor and slow switching of AV1
-13 VECM for the capstan motor.
This voltage also obtains the 12VS switched voltages via TW001, TW002, TW003, and DW006
for the tuner and the IF, and two 5VS voltages. The first polarises Pin 80 of IT001 via Zener
diode DT067. The second powers the HF and IF stages, video processing, audio processing,
and switching via TX083.
Pin 12 via DP066, CP066, LP066, CP067, stabilised by DP067: a 5VE voltage supplying
power to the control and programming stages, the tuner, and the switching.