Wow! "undervalued" ??? Those things are not well liked around here. I'm happy, though....I have made quite a bit of money over the years doing freelance maintenance and keeping them going.

I am not at liberty to tell some of the worst stories but let me make 2 suggestions.

1. The switches will fail. There is only so much you can do with contact cleaner and then they need to be replaced. It is very easy to damage the foil doing this. This is best done with a vacuum system something like this...

Tenma 2-in-1 Rewark Station - Hot Air and Soldering Iron | 21-11420 (2111420) | Tenma

Don't even try it with braid or the manual spring-loaded pumps.

If there are some switches that you know you will never use, just jump them out. This may be awkward or impossible in some of the gang situations.

2. There are variants of the faders. All of the ones that I have seen use a VCA card. It has 2 TLO-72s, 2 5532s, and 2 Valley TA-101. The Valley TA 101 is a precision matched transistor array. The problem here is that these things are almost impossible to find if they fail. Fortunately they rarely fail. If you (or anyone else) find yourself in a situation with a failed TA-101, contact me. I know where there are a few spares of these and I will try to hook you up with the people who have them. No guarantees, but I will do what I can to keep you going.

Yes, the preamps are strange but it sounds like you are dealing with that problem.

Good luck with this thing!

Thanks for the information! All the faders in mine are without the VCA.

The switches are a PITA and I had to clean them thoroughly before it would even pass signal. Can you recommend a good switch lubricant? I want to avoid the Caig products if possible.

Do you mean a vacuum desoldering station? I thought the hot air blowers were for SMT.

BTW, the prices on Ebay are not the prices they actually sell for. Try dividing by 10 or 20. duh