Just got an F100 in what appears to be fairly good, but obviously old condition. When it first arrived, I tested it out, and it seemed to work beautifully. Took it to it's first gig (mostly just to try it out in practice, I didn't really need it), and hooked it up. It heated up fine, but the pump wouldn't run.
Now, back in the shop, I measured the voltage on the pump leads, and it seems to be 110VAC, whether or not the run button is pressed (timer is turned off on the timer remote). I also measured with a scope, the input voltage to the pump optocoupler. You can see a train of pulses when you press the Run button.
So, to me this says that the problem is either the SCR, the pump, or the optocoupler.
With the power off, the resistance across the pump windings is high, but not open (about 1 Meg).
What should the resistance of the pump windings be? Is this indicative of a bad pump?
If this is the case, does anybody here have a surplus pump they wouldn't mind selling?
I haven't really worked much with SCRs but I seem to remember they require a load to work properly, so is this why the voltage is 110VAC? Is the pump not giving enough load to the SCR for it to work? Or is this a bad SCR?
Thanks,
Jeff
