Using the debug pages from Commonsound, there are 6 test points in the phase stage.... The ones that are to be 2-4v are on my unit measuring about 5v. The ones that are to be 5v are measing 3.5v. It's like they're reversed.
I made the PCB backwards (forgot to flip the image) but I soldered the ICs and Trannys to the solder side so that they still match up with the wholes.
The height control is also a bit wacky. The unit only phases when the height control is in one particular spot. It also does not have the desired effect on the LEDs. But the round led blinks along with speed so it's not a problem with the led driver. Any ideas on any of this stuff?
Thanks,
Michael
I could only suggest making the PCB the right way around and trying again. Otherwise it is difficult to debug, even for those of us who have made a bunch of them before. Sounds like something is whacked with the DC voltages, for sure.
Mike
Well, since I built this thing using the old layout there were 2 resistors from base to ground of the Input and Output stages missing. Slapped them in and not much difference.
On the debug pages, at point 4, the emitter of the input transistor should have a DC of 7-8 correct? I'm only measuring ~2.4v. Other than this and the measurements on the phase stages I can't find anything wrong..hmm...
While it has it's bugs, it's not a bad sounding phaseur! It's pretty lopsided now and the sweep isn't too strong but i'll get it worked out eventually I'm sure. Damn, the ring function blows me away.....
Any one have ideas?
Michael