Hi,
I have a slightly odd problem with my nearly-resurrected Sirius 24. After replacing some damaged hardware (faders and keycaps), I found that the battery wasn't holding charge and needed replacing. I replaced the battery and then found that this would discharge again within hours. After some speculative component swapping I finally found a defective diode (1N4148) on the CPU board that was causing the battery to discharge quickly. I replaced this,and now the battery holds charge and the board boots reliably. However, when it first starts up the output voltage at 100% fader position is low. In fact, it's about 8.5V, and the 0% output voltage is also high, maybe just over 1V. The voltages are proportional to fader position, though. Over a period of about 30min-1h it settles down to the correct voltage. I can't seem to stop it from doing this, even after replacing the resistors that are connected to the jumper block that controls the output voltage and some nearby capacitors that I thought might be questionable.
This seems to have improved the situation slightly, but so can sticking your finger on the leads to the resistors- they're between 300K and 470K so skin resistance will make a significant difference.
I have no idea what causes this. Has anybody had the same problem?
The other Sirius we use in our regular venue seems to have the same problem, but less seriously. It takes about 5-10 minutes to 'warm up' to the correct voltage level, so that all the dimmers are slightly 'low' on start-up.
Thanks,
Dirk