FetDIv2 Build Thread

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Joe Malone
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FetDIv2 Build Thread

Post by Joe Malone »

FETDIv2 Build Thread

Notes and Errata
1. 100uF 50v caps in the kit are Non Polar and can go either way around. The 100uF 50v caps have incorrect plastic sleeve showing negative strip which you can ignored
2. 3 way terminal blocks dovetail together to make a 6way terminal block before fitting to the PCB.

FetDIv2 is just built from the PCB overlay from the lowest height parts to the highest. See photos at bottom of this thread for more details.
Only the TRS sockets, 2 Fets, 24v relay, 10 pin header and terminal blocks have to go the correct way around for polarity.
Start with the resistors,
then 24v relay with strip at correct end.
then 220pF ceramic cap. Should have 221 written on it.
then 0.1uF caps can have 0.1uF or 100nF written on it.
then Fets and leave them sitting at the same height as the the 0.1uF caps and flat face to face.
then the 10 pin header polarized correctly.
then 6 way terminal block polarized correctly.
then TRS socket.
then the 3 x 100uF 50v cap. They can go in either way as they are Non Polarized.

If you want to run the DI on 24v dc instead of the normal 48v. Replace 2k7 in red box with wire link.

If you would like to have a manual DI/MIC input switch follow below photo

You can change the DI input impedance by changing the 2 x 2M2 caps marked with * . These two resistors end up in parallel on either side of the input 0.1uF cap so input impedance is always half the value of these 2 resistors. So DI has 1.1Meg input impedance normally. If you want 100Meg input impedance change both to 200Meg resistors etc.

Joe :-)
JLM Audio
Capturing Audio without Injury

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