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FERNSEH · 19th May 2018, 3:42 pm

In fact the fault in the video amplifier was a simple one. The 15Kohm anode load resistor was short circuited to the centre spigot of the valveholder. Repositioning the component effected a cure.
40 volts of active video + syncs is present across the load resistor of the video cathode follower.

Assuming the CRT is OK this set will display a well contested picture.

The sync separator is functioning correctly. High amplitude negative going sync pulses are present at the anode of the sync separator valve.
The interlace filter diodes will need replacing.

DFWB.

19th May 2018, 3:42 pm	#18
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTM4. In fact the fault in the video amplifier was a simple one. The 15Kohm anode load resistor was short circuited to the centre spigot of the valveholder. Repositioning the component effected a cure. 40 volts of active video + syncs is present across the load resistor of the video cathode follower. Assuming the CRT is OK this set will display a well contested picture. The sync separator is functioning correctly. High amplitude negative going sync pulses are present at the anode of the sync separator valve. The interlace filter diodes will need replacing. DFWB.