Restoration of Magnavox tuner amp 57-03-00

[rolf logan]

Hello Colleagues,

I hope your Sunday is going well. I'm doing what I love, fixing an amp. I lack formal training in Electronics, but I have successfully restored 5 stereo consoles. So, my "trade" knowledge is limited.

On the desk is a Magnavox tuner amp 57-03-00, hooks to a Magnavox 175-GH amp. I don't have the model number of the actual Stereo Console, but it is, my best guess, 1959 era "Magnificent Magnavox".

Issue is that I have to replace parts K1 & K2 on the tuner amp, printed board. These parts are , which are on the parts list as "Component Combinations". Both are referred to in the attached screenshots of the parts list + overhead photo from Schematic. As you can see from the first photo, they need to be replaced.

Problem is I have no idea how to order a replacement. I know what a capacitor is, a resistor, but does anyone know what they are referring to here and how I can get a replacement? Thank you to any of you who respond. Much appreciated.

 

[daveshel]

Looks like those are what Dynaco called PECs. Packaged Electronic Circuits, consisting of resistors and capacitors. What leads you to believe they should be replaced?

 

[rolf logan]

In the attached photo 1, seems there is bubbling? It looked like it should be replaced. I didn't test it. Frankly, don't know how to.

 

[FlaCharlie]

In the attached photo 1, seems there is bubbling? It looked like it should be replaced. I didn't test it. Frankly, don't know how to.

Some components were coated with wax and when they get hot the wax will bubble up a bit. Nothing to worry about unless there is some other issue.

PECs are are essentially unobtainable so, if there is an issue, you need to build your own on a perfboard so something similar. Here are the schematics for K1 and K2 if you decide to build one but I suspect they're fine. That said, I know zilch about tuners so . . .

 

[tom3]

I think Magnavox calls these couplates, early IC of sorts. You could build your own from the schematic but I'd check for signal ahead of it first. Some of those have paper capacitors inside and do go bad (from what I've read)

 

[cademan]

That's just bubbly looking wax. All of mine look like that.

They don't get hot and don't really need to be replaced. A PEC or Packaged Electronic Circuit usually only consists of a few resistors and capacitors. If the tuner is working okay or maybe a little distorted, it is usually bad electrolytics or high reading resistors. Never assume or go by looks unless something is blatantly black or scorched.