3 November 2022 at 04:41
#25789
Hi Mark,
I am currently in the process of replacing all associated components in both the servo motor control and solenoid circuits. Upon inspecting TR-22, (the BC143 transistor)I found that it does not test properly and I compared it with the one on my other 4004 board that functions properly. I suspect that this transistor has failed and I ordered a NOS replacement from Littlediode in the UK. It should arrive in the next few weeks. I will report back the findings and hopefully this solves the issues with this board. Thanks!
Ian