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Old 31st Aug 2019, 9:42 pm   #202
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Join Date: Oct 2016
Location: Maroochydore, Queensland, Australia.
Posts: 2,679
Default Re: Baird T5 restoration project.

Originally Posted by FERNSEH View Post
Hi Argus,
I've redrawn the circuit of the DC restorer to show the 500Kohm resistor in parallel with the WX6. Note also the 200Kohm resistor in series with the diode.
The third attachment show the underside of the T5 EHT unit. No DC restorer was fitted in this receiver.
The purpose of the resistor in series with the diode is to isolate the diode's capacitance from the video signal. If it is too large the restorer's effectiveness is diminished. The typical value RCA chose was around 10k to 47k as I recall, it needs to be at least as big as the anode resistor in the plate of the video output valve and not much bigger in value. Maybe, looking at the photo you posted, its a 22k not a 220k ? Check it on the meter, if it reads 200k, maybe its a gone very high 22k ?
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