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Old 18th Oct 2021, 8:58 pm   #21
AdrianH
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Join Date: Mar 2020
Location: Blackburn with Darwen, Lancashire, UK.
Posts: 894
Default Re: 5FP7 project starting with the focusing coil.

It takes me a few days to do the metalwork and build up the parts for these projects, but the next stage has been completed to a point. The EHT unit is working and provides approx 3.8kV for the final anode, 250 to 260 Volts for g2 and down to -42 volts for the control grid.

I have used a EL91 7 pin valve to drive the LOPT, a few component changes to get it up near 10KHz frequency, but it seems to be be working OK. seeing how long the EL91 will last as it is not meant to handle the voltage spikes but the one in the home made TV is still OK.

Click image for larger version

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Short video

https://youtu.be/el3mzvLhkHc

Be safe.

Adrian
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