The Ten-Tec folks gave me these in about
2011
You can enlarge these PDFs by many hundreds %, with no degridation.
I've been meaning to post these for 5 years, and I finnaly did it!
I hope they can be of use to anyone who needs them.
Once you've looked at it, and you would like to download it!
There should be a download icon near the upper right corner of the screen.(FireFox)
If you're not using FireFox, there should be a "save" or "download" somewhare on the Browzer page.
The window should ask where to save it, and you're done!
538 DC Input Schematic
538 Head Phones Schematic
538 Keypad Schematic
538 Logic Board Schematic
538 Low Pass Filter Schematic
538 RF Board Schematic
538 ce_schematics_Logic & RF