UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

dazzlevision · 26th Jul 2019, 8:54 pm

Another possible cause of virtually no signals on UHF or VHF might be the screen feed (g2) resistor of the mixer valve in the VHF tuner - usually around 22kOhm, half watt carbon composition type. Worth checking, I’d say. The mixer is also employed as an additional IF amp stage on 625 operation, so it would affect 405 & 625.

I’d also check the screen feed resistors of the EF183 and EF184 stages.

26th Jul 2019, 8:54 pm	#4
dazzlevision Dekatron Join Date: Sep 2003 Location: Near Swindon, North Wiltshire, UK. Posts: 3,621	Re: KB WV20 Warwick Another possible cause of virtually no signals on UHF or VHF might be the screen feed (g2) resistor of the mixer valve in the VHF tuner - usually around 22kOhm, half watt carbon composition type. Worth checking, I’d say. The mixer is also employed as an additional IF amp stage on 625 operation, so it would affect 405 & 625. I’d also check the screen feed resistors of the EF183 and EF184 stages.