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Folsom EC7293: PVI Powered Frontend, 60/120w 8/4ohm

Jeremy,

In your first post, I find it interesting how you illuminate your work.
From what I can tell it looks like your using a small LED lamp above the pcb, plus some sort of led/lamp shining up from underneath the pcb.

My older eyes could sure use some info on how you illuminate your work.
 
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Jeremy,

In your first post, I find it interesting how you illuminate your work.
From what I can tell it looks like your using a small LED lamp above the pcb, plus some sort of led/lamp shining up from underneath the pcb.

My older eyes could sure use some info on how you illuminate your work.

I think those are the LEDs for the solar cells to power the error correction part of the amp.
 
Founder of XSA-Labs
Joined 2012
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This is interesting. How does a photovoltaic power supply isolate the power fluctuations from the front end? How is it better than say typical RC (circa 10k and 100uF) added on the rails between the VAS and input stage? The LED brightness will fluctuate with fluctuations and photovoltaic module will respond accordingly. Is the LED drive then filtered with an RC?

Optical isolation of power supply is handy when trying to galvanically isolate HV from more delicate circuits. I have used 15kV optically isolated opamps. But the PSU for the HV side needed up needing a triple 5kV DC-DC to get 15kV isolation.
 
Founder of XSA-Labs
Joined 2012
Paid Member
I don't like my amps to glow too bright. It makes debugging very hard as your eyes get overwhelmed by the brightness. I find a single blue LED to often be too much and I have to cover it with a black piece of shrink tube condom. I agree it is cool to see in operation, but not in development.

Do you have schematics for this or not shown until one buys the board?