Video on Balancing a Phase Inverter

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pompeiisneaks
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Video on Balancing a Phase Inverter

Post by pompeiisneaks »

The new video is up... How to balance a phase inverter!


~Phil
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ChopSauce
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Re: Video on Balancing a Phase Inverter

Post by ChopSauce »

Thanks Phil!

I'll watch this right now - but I'd like to know what kind of trimpots you use for PI balancing?

I can almost only find 1/4W (and the same applies for the common 110k plate resistor, as well.)
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xtian
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Re: Video on Balancing a Phase Inverter

Post by xtian »

Those are Phier trimmers, and 1/4 watt should be fine for 12A?7 plates.
I build and repair tube amps. http://amps.monkeymatic.com
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Re: Video on Balancing a Phase Inverter

Post by ChopSauce »

Thanks!
dbeasley
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Re: Video on Balancing a Phase Inverter

Post by dbeasley »

Pompeii,

Are you scoping the plate load outputs of the PI before after the coupling caps going to the power amp stage?

Also, I seem to recall folks in the past mentioning that the optimum way to do this was to tie power tube cathodes together per pair and measure the voltage differential as opposed to tweaking PI output - as this takes the power amp more into consideration. Any thoughts on this?

Also, really enjoyed you explaining using the math functions. Suddenly my Rigol scope looks a lot more handy!

Sent from my SAMSUNG-SM-G920A using Tapatalk

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Re: Video on Balancing a Phase Inverter

Post by pompeiisneaks »

I took the output just out of the other side of the coupling capacitors from the PI yes, I realized after I was done with the video, that I didn't explain super clearly WHERE I connected it :).

~Phil
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