KMV254c: Gefell MV691 to KM54c modification.

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Hey!
Thanks for Your hard work!
I would like to buy 4 PCBs for the Mic Body and 2 PCBs for the Power Supply!
I have 3 691 amd one 750 which i like to convert!

Very nice project!

Bye Friedemann

That’s great! I’ll get those out to you when I’m back from tour at the end of April! I’m stoked you’re gonna get into this project.

The pm750 has a capsule with the same element as the m94 but it does not have the 10m dropper resistor so it is not swappable with the other capsules in the system. If you want to use the capsule with the KMV you will have to set the capsule voltage to 40v. The kmv has the 120v split in half by two 300k resistors. If you swap one of them for 600k (as in the the original km54 circuit) you will get the 40v you need. But make sure you swap the correct resistor because otherwise you’ll get 80v at the capsule and will likely cause collapse and damage due to arcing.
I’m working on making a mod for the capsule to turn it identical to the m94 by installing a precise ring to allow the 10m to join the circuit.
 
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