# 2022-08-24 Power-on test
As mentioned, power was orginally delivered through a 6-pin XLR socket on the rear, internally wired to a Molex connector (which does not follow the Molex standard).
XLR-6pin | Molex pin* | Cable colour | Signal |
---|---|---|---|
3 | 1 | Red | 5V - for driving the logic, LEDs, and VFD |
4 + 1 | 2 | Black | GND |
2 | 3 | White | ?? (not yet traced) |
6 | 4 | Yellow | 12V ?? - for driving the incandescent bulbs (in the majority of the lighted keys) |
5 + shield | n/c |
A power-on test was inconclusive. I had wired up a pc power supply with GND, 5V and 12V to three of the four connectors on the main board's Molex socket (sans yellow), but got no life signs (no beeps, no lights, no text in the VFD). I did not check for signals on the RS422 port.
Possible explanations:
- I wired it up incorrectly.
This may be; I'm only human after all. In any case, I detected no magic smoke leaks. - The power supply couldn't provide sufficient amps. This is a likely explanation, because the power supply was from a somewhat dinky office desktop pc. I have other supplies available to test with. Unfortunately, the installation guide only states total consumption (42W peak) but does not break it down by voltage; I suspect the 12V needs significant amps to run the VFD.
- The control panel is defective. How likely this is is hard to say; the console has a few exterior scratches but no tell-tale marks of hard drops or deteriorated internal components.
Update: I had indeed wired it up incorrectly. I'm going to blame the colouring; R/Y is flipped compared to common pc usage.
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