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I would like to use a 3PDT Vari-Brite board without a trimmer, just like a standard 3PDT wiring board. Obviously the trimmer must be wired in series with the CLR to affect the overall LED brightness. So if I leave out the trimmer, will the board operate the same as the standard 3PDT wiring board as it appears to me it just connects to the CLR? Or will I need to add a jumper somewhere?
Stupid me – soldering and de-soldering the negative LED wire a couple of times to and from the board ruined the trace back to the eyelet for 3PDT lug #5. First time I have ever ruined a PCB in nearly 20 years of building pedals. Guess there is a first time for everything. I have left a couple of the Vari-Brite boards so I was wondering if I could use them without a trimmer since I don’t have any of the requisite trimmers on hand.
Hi Big O.
The trimmer is in series. If you have a CLR at the CLR pads then you would need to put a jumper between lugs 1 and 3 of the trimmer section.
Thanks Barry! I figured I might need a jumper. I realized after I posted that I could check the path with a continuity tester but your response saves me some work.
For anyone that is interested, below shows the connections that have to do with the LED as done with a continuity tester. Some of these do not conform to the exact traces on the board, but are for illustration purposes. All of the 9V DC power connections are in yellow. The output pad from the CLR connects to pad #3 of the trimmer as seen in the pink trace. The path from the trimmer to the (+) side of the LED is in light blue. If you want to omit the trimmer, all you would need to do is jumper 3 to 1 or 3 to 2 of the trimpot pads (eg purple dotted trace). Trimpot pads 1 and 2 are connected to each other.
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