Paleo-Electronics

Clueless Idiots and High Voltage Vacuum Tubes Really Do Mix!

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Entries Tagged as 'medalist'

Replacing the Cap Can

February 20th, 2012 · 8 Comments · Amp Repair, Medalist Debug

The first things to go generally on these old amps is the power filter capacitors and these are often all rolled into one single ‘Cap Can’. Here’s mine in place in a GA-5 Medalist. These are (IIRC) wax paper and foil capacitors and are sealed with wax. It is electrolytic but has a single ground […]

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Debugging the Medalist – Power Supply Filtering

March 28th, 2011 · 2 Comments · Amp Repair, Medalist Debug

As you might recall from two posts ago (“Scoping the Power Supply”) we were unable even to scope the power supply ripple at TP3 and saw a hideous deformed thing at TP5. The lack of filtering certainly indicates that C4A (the 20μF from the cap can) was blown. Since that big funky cap can itself […]

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Debugging the Medalist – Part I

March 26th, 2011 · No Comments · Amp Repair, Medalist Debug

Allriiiighty then! Time get inside the Medalist and see whats up. First, the seller reported low output and loud hum. Amp is in great shape for a 44 year old amp, only the grill cloth is obviously deteriorating. Original schematic stapled inside will be a lifesaver. The only other thing of interest on the outside […]

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Now on the bench : A 67 GA-5T ‘Medalist’ Skylark

March 26th, 2011 · No Comments · Amp Repair, ebay, Uncategorized

Preamble When last we met I claimed, without evidence, that I was in possession of an authentic, original schematic for a 67 GA-5T Skylark. How could I guarantee such a thing? I took the schematic out of a 67 myself! I just bought one on ebay after all the doings with Patrick and trying to […]

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Oh what a find! GA-5T Skylark ‘Medalist’ schematic!

March 22nd, 2011 · No Comments · Amp mods, Amp Repair, Schematics

Ok. I can guarantee that this is the schematic for a ’67 or later GA-5T. This is commonly called the ‘Medalist’ styling and an example with some info is found at John Kings site. How can I guarantee that? I’ll get to that later, but for now, trust me. Full size file is almost 3 […]

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