Recent content by PJS

I think that Stickman is correct. both those locations would usually be biased to about 4 - 4.5v but both would get that bias voltage from different places, and may be slightly different. It would be interesting to see if the voltage at the output changes if you pull the IC. You also should...

Looking at your voltages pins 7 and 8 of IC3 do not look right. I am not sure what they are supposed to be exactly, but they will need to be roughly halfway between 0 and 8.7v for audio to pass well. The bias voltage is set by the 50k trimpot. I would be setting the trimmer to give about...

So do as I suggested above and temporarily change it to be using the internal programs. That will test to make sure the EEPROM is properly programmed. Pin 13 connects to a resistor which then connects to 3.3v. Lift the 3.3v end and connect to ground instead, then the internal programs will be...

You are correct - there should b no connection between those points. Somewhere you have introduced a short. Most likely poor soldering. Show us some photos maybe, and visually check everything.

Are you using an EEPROM or internal sounds? If you are using an EEPROM try temporarily setting it to the internal sounds and see if they all work. May be a problem with the software in the EEPROM and this will be a pretty good way to check that.

From the datasheet it looks as if anything with the Z is the same chip just in a lead (Pb) free package. The A has slightly different input offsets etc. Not sure that it will matter much for audio though.

More likely something dowstream is pulling too much current - check for shorts.

If you try and pull too much current from a regulator it will lose regulation (and get hot). An easy was to pull too much current is a short. I am thinking that it is likely that the FV-1 or the eeprom is broken and drawing too much current. If the eeprom is socketed that is easy to remove...

You could solder the jumpers in place, but I would leave the holes for the DIP switches untouched. I would solder jumpers to the solder side of the board and connect the pads that the DIP switches connect to.

I don't think so (having not built one). The build docks say that if you are leaving out the key input entirely then you can connect the switched tip pad directly to the tip pad and leave out the socket. If you are using the key input at all then it seems as if you would need to wire it with...

I once spent a long time troubleshooting a build when I finally worked out that I had plugged the guitar into the output and the amp into the input.

I think that it is a little bit more complicated than the above. The documentation calls for the use of tip and switched tip (and sleeve for ground is assumed - in this case I am thinking ground is via the physical connection between the jack and the case). According to the Tayda...

Nope. You should be getting voltage on the resistor side and gnd on the switch side. If your switch is giving you 8.8v then it is broken or wired incorrectly

That is why I test each resistor with my multimeter before inserting it.

The 2n7000 FETs in the OCD have protection diodes - it is these diodes that actually do the clipping - nothing to do with the actual FET