Update – May 15, 2018: I have almost finished restoring the bottom of the unit (where most of the components are) and expect to have it working in the next week or less!
Update – May 12, 2018: Here is the Schematic with the parts labeled, this way you can easily see where you are on the schematic while working with only one paper!
Sprague TO-6A Schematic Parts Labeled Hallman Labs
Decided to do what they call a shotgun restore of this unit. I will be replacing all fixed value parts including capacitors, resistors and I already got replacement tubes including one September 1964 JAN Philips 6AB4, one Sylvania USA Oct. 1970 6C4WA, an Amperex USA July 1968 6BL7GTA and finally a Sylvania JAN 6E5 VT-215 “Magic Eye” tube. I already had all the capacitors I needed to replace everything with almost factory identical equivalents including Sprague: Black Beauties, Atoms, etc.
Before I start to move/change things I need reference pictures in the chance I lose my spot where I was working, or can’t tell where one leg is meant to go. As you can see, this unit has a lot more going on than my CDE BF-50 cap analyzer.
I am working with AntiqueRadios.com forums to get my unit back up and working, this way I can finally begin to sell my treble bleeds and individually tested tone caps with a 30 day guarantee.
You can find my thread detailing my progress and the community help here: http://www.antiqueradios.com/forums/viewtopic.php?f=8&t=340116&p=2851870#p2851870
I hope to have this device working by next weekend, as long as the few parts I did need get here when they say they will.
PS: Does anyone know where to find the 7-27H combination resistance and amperage meter? I can’t find anything like it anywhere without having to buy a 2nd TO-6A. Note: the 7-27 found on the TO-6 will also work.
Forgot to show the bottom side of the unit! Here you go! I have a labeled schematic coming soon.
