Thank You . I have the original users manual and as you stated it is very sketchy. I also have S/G FM-10 which worked the last time I tried it. I have all the manuals for the FM-10 if they would help you. My experience with the FM-10 is if it has been siting for any length of time is to spray the bank of switches with radio shack or equivalent switch/pot cleaner and it will wake up.
Thanks again for trying to find a service manual for me.
Frankly I don't really want the FM-10. It's too big and heavy, and I have other instruments that can do the same job better. It was given to me and after spending a couple of hours with it,, I realized that it doesn't fit in with the rest of my lab. I did some switch spraying but that didn't solve all of its problems. So my plan is to tear it apart and throw away most of it. I tried to unload it on ebay without success. Of course, packing and shipping for a bulky 50 pound instrument wouldn't be cheap for anyone but a local buyer.
I also have problems with other obsolete gear, such as a Leader 322 signal generator that would be nice to have. It has dropped out of phase lock and so far I haven't been able to repair it.
Good luck with your Helper unit. There are so many units out there that only need a bit of help.
