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Old 18th May 2016, 11:28 am   #161
PJL
Dekatron
 
Join Date: Sep 2005
Location: Seaford, East Sussex, UK.
Posts: 5,997
Default Re: HMV 653 Broadcaster all wave.

HT voltage too high and V4 anode current too high resulting in unstable output stage that could be responsible for capacitor damage from flyback.

You need to get the HT voltage and current right before the set can be left powered up to do any other diagnosis.

There are several possibilities:
1. The readings are wrong
2. The field coil is not wired in correctly
3. The field coil is the wrong value (1710 ohms) or is arching internally

As the set has been rewired, I suggest you start by checking your wiring on the speaker assembly. Then checking the resistance of the field coil by measuring between the electrolytics C25+ and C28+ terminals (Broadcaster).

If this is all OK, connect your meter between C25+ and C28+ and power up (be careful as the meter will be at 300+V). The voltage should start rising after a minute to around 100V. If it fails to start rising after a couple of minutes then switch off.
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