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Old 29th Feb 2020, 8:09 pm   #6
Heatercathodeshort
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Join Date: Jun 2005
Location: Warnham, West Sussex. 10 miles south of DORKING.
Posts: 7,666
Default Re: Pye VT4 - no EHT

Agree there Techman
Two hot spots on the V4/VT4 chassis are the line output transformer and the scan coils in that order.
As suggested the boost capacitor and the line coupling capacitor to pin 2 of the PL81 must be replaced. The width inductor can go shorted turns dampening the LOPT. Disconnect it for a test. The chassis will work very well without it.
If you have a healthy spark at the anode of the EY51 [not shorting the test screwdriver blade to chassis] either the EY51 has an O/C heater or maybe the heater winding is faulty. You can wire in a 6v radio panel bulb as a test after checking the windings continuity of course.
It is possible the EY51 has an internal short but this would damp the anode spark.
Just a few things to try. John.
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