I'm finally getting around to fixing, updating and working on my 500 plug in collection.
I have a, apparently, rare TM504A chassis that was modified by a previous owner so not all modules work in all slots and sources do not talk to destinations. It also has an oscillation in the power supply that I need to fix (Classic issue with how they did the feedback on the power supply). It is finally time for me to understand the back programing header and how to use it so that say my freq counter can read the oscillator or the volt meter read the power supply though the back plane while still being able to swap out modules.
I have been unable to find a manual or schematic for this unit, but there are plenty for the TM504. Is there any real difference other than the addition of a fan and switch location? Is the TM504 service manual good enough or if not where can I hunt down a TM504A one?
I sure wish there was a modern version of the 500 modules. I have some great modules with no current product options. I use the filter/pre-amp all the time at work and once I updated the op amps it works better than the current version by another vendor. But these things sure are getting old and I wonder if it is worth my time to keep them working for bench work any longer. For now I'll keep trying.
Thanx,
Hawker
