Headtrip2 No effect

[aienco]

Hello, I am new to Madbeanpedas however I have been building kits for over 40 years, recently pedals. This, by no means makes me any good at troubleshooting. My issue is the Pedal has no effects when switched in. LED's, Switches, Pots, all do as they should. All voltages EXCEPT Pin 5 on the FV1 are good. Pin 5 reads mV? I have reflowed all solder joints, including FV1, I have tried a spare Eprom. I can hear static oscillating when effect is switched in. I assume this is the crystal. Before I go and try finding and replacing the FV1, is it possible it could be anything else? The circuit shows Pin 5 going nowhere and labeled clip??

Any advice would be greatly appreciated.

[madbean]

pin5 doesn't have anything connected to so you can disregard that.

If you have an audio probe, I would check pin1 or 2 of the FV-1 to ensure it's getting audio signal to its input. Then check pin28 for audio output. If you have input but no output, try temporarily grounding pin13 (or the side of R14 that connects to pin13). This will enable the internal FV-1 programs. If you get some effect output with pin13 grounded, something is wrong with the EEPROM (the one that has the HT2 programs).  If you still have no effect output, then it's definitely something up with the FV-1 itself.

[aienco]

Thank you kindly for your assistance. With pin 13 Grounded, Pin 28 is still silent. So I guess its the FV1 at fault?

[madbean]

If all the voltages on the FV1 look good I would look closely for any solder bridges between the pins. Use a continuity checker to make sure adjacent pins are not bridged (unless they are supposed to be according to the schematic). Feel free to post a close up shot of the top of your build, too. We can take a look at it.

[aienco]

Well I am making SOME progress. I happened to have a spare new FV1. I always try to buy 2 of the important things if budget allows. As you can't seem to buy the FV1's here in Australia, I bought two.

After soldering it in, I now get the correct output with affect on Pin 28, however still just standard (no effect) on the output. So I will have to investigate what I have done there.

[aienco]

I can now confirm that it is all working correctly. You were spot on, the FV1 at fault. Now to try and source another as I have another Headtrip2 board that I wanted to build up for a friend.

Thank you kindly again for all your guidance and patience.

[madbean]

Did you swap them on the same PCB? Reason I say is maybe there was a soldering issue that was resolved when you put on the new one. IOW, perhaps the original chip is not bad (hopefully not b/c they are so expensive).

[aienco]

I did swap it on the pcb. I did re flow it when the fault first appeared, but you may be correct. Perhaps the chip is not faulty. I will carefully try and solder it onto the new build and if it plays up on that as well, then I will know it was the chip.