After having to jury-rig a setup to tune the trimpot on my T620’s driver, I thought there had to be a better way. So I had the idea of building a test-bench of sorts. Something to hold the driver/emitter/pill and maybe give them a bit of sinking, a power switch, a battery cradle for 1-3 18650’s, and both an ammeter and a volt meter built into the board so I can monitor voltage sag and see how the trimpot adjustments are working (and to calculate total wattage).
I’m having a spot of trouble finding components. The ammeter, I could plug my DMM in series but that just seems a bit inelegant. As to volt meters, this is the closest to what I want that I’ve found, but I think it’s resolution stops at tenths of a volt and I’d much prefer hundredths. Hobbyking has a combination volt meter/ammeter but it needs 5v just to get going, and that rules-out playing with single-cell or most AAA/AA/C/D lights.
Any help would be greatly appreciated, especially potential suggestions for successfully sinking the driver and keeping it removable from the bench. 