Apox volume, input select & front board

[GeeVee]

Hi All

I have the following APOX items for sale

1.Front panel board IR1, Fully assembled tested and 100% working order

2.Input select boards (balanced) x 2, IS1 Fully assembled tested and 100% working order

3.Volume board (balanced) Apox-1 Rev 3. Fully assembled but has issues.

I purchased all of these items just recently from a diy audio member, with the full knowledge that the volume board was not fully operational. The seller was very honest. I took the gamble.

I was sure that I could find the problem.

Anyway, this is what I have found out.

All of the analog side, ie relays, resistor network is correct. I have checked against the excel calculator on the Apox web site, and all appears in order.

Unfortunately, I believe that as the rotary encoder is being advanced, incorrect relays are being selected.

Basically, there is a huge decrease in gain between steps 75 to 76, 95 to 96 and 105 to 106.
From step 135 up to 255, it is all over the place.

I am 90% sure that the problem lies within the source code of the microprocessor, as this is responsible for relay selection.

Apox have sent me the source codes.

Unfortunately this means digital / microprocessors / compliers / assemblers etc, and all of this is well beyond my knowledge, and don’t think I could do it.

Believe me; I would rather not sell it, as I wanted this unit for a project very badly. I just have to be realistic with my abilities.

If anyone can help me, so I don’t have to sell it, that’s great, if not sale is inevitable.

All I am asking is what I paid for it, which is $160 AUD for the entire set.

Regards

George.