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Old 19th Mar 2019, 9:16 pm   #61
Uncle Bulgaria
Heptode
 
Join Date: May 2016
Location: Cornwall, UK.
Posts: 537
Default Re: Ferrograph 4A: Restoration advice needed

Right, so the circuit would be loaded by the same amount if the measurements were taken at the same range, but some just wouldn't cause significant deflection? Changing the range would alter the load and the service document values would reflect this, I suppose?

I'm going to check with the AVO as soon as I get it out, and see if that made the difference.

I'm in the process of adding the modification written up by 'Pichacker' in another thread from a few years ago, when he was fixing up a Vortexion. It's an RC filter on V3's grid, to block DC and give a constant grid-leak rather than the current arrangement where the volume control is the grid-leak. That will be done tomorrow when I get some more yellow capacitors.

I have also put a tape on, and shock horror! it plays. I'm really chuffed, and it's thanks to the input I've had here that I've been able to make sense of a lot of the work I've had to do.

Now the adjustment begins...
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