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FERNSEH · 13th Jun 2018, 7:58 pm

Thanks to Brian for posting up the pictures. Still work to do on this set before it can be signed off. The width control doesn't work, it's likely the coupling capacitor between the line oscillator and the grid of the PL36 has a leak. The Decca has a stabilised line output stage which employs a VDR as the device to rectify the flyback pulse to produce the controlling negative bias for the line output valve.

The picture needs more height, it's likely more capacitors need replacing. The vision AGC isn't working properly and again it'll be those Hunts capacitors.
Switching over to 625 lines is facilitated by selecting the "UHF" position on the VHF tuner, except it doesn't, that's something else to look into.

DFWB.

13th Jun 2018, 7:58 pm	#23
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Decca DR101 dual standard TV Thanks to Brian for posting up the pictures. Still work to do on this set before it can be signed off. The width control doesn't work, it's likely the coupling capacitor between the line oscillator and the grid of the PL36 has a leak. The Decca has a stabilised line output stage which employs a VDR as the device to rectify the flyback pulse to produce the controlling negative bias for the line output valve. The picture needs more height, it's likely more capacitors need replacing. The vision AGC isn't working properly and again it'll be those Hunts capacitors. Switching over to 625 lines is facilitated by selecting the "UHF" position on the VHF tuner, except it doesn't, that's something else to look into. DFWB. Last edited by FERNSEH; 13th Jun 2018 at 8:06 pm.