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Old 30th Aug 2019, 8:48 pm   #195
beery
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Join Date: Jun 2006
Location: Ware, Hertfordshire, UK.
Posts: 773
Default Re: Baird T5 restoration project.

Hi David,
if you want to try the T20 method then you can disconnect the grounded end of the CRT heater current control. The main complication is that the brightness control plugs into the EHT unit, but you would need to get an HT feed from the main PSU to the control, and join the bottom end of the EHT supply to chassis.

Lets look at some values...
I don't know the value of the T5/T23 brigntness control.
From the T20 circuit I posted earlier, The brightness control (VR4) is 10K. The resistor that feeds is (R18) is 80K.
The other R18 in the TRF unit is 500K.

Cheers
Andy
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Last edited by beery; 30th Aug 2019 at 8:48 pm. Reason: spelling
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