Time to pull the 2020's Relay & Power boards

10sguru

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Time to pull the 2020's Power Supply & Electrolytic PCB's

Okay, thought I would start a new thread for this which was mentioned in a previous post of mine. Merrylander I would like to take you up on the offer of sending me the drawings/masks of these two boards as a friend of mine has agreed to see if he can help me etch new ones. Also as I remove the boards is there a preferred method for disconnecting the wires? Should I desolder the soldered connections and cut the wire wrapped connections to be resoldered and shrink wrapped later as I read somewhere on this Board that the wire wrap pins are an odd size which makes finding a suitable gun difficult. I will need to remove all wires that are connected to both boards and just wanted to know how the experts would handle this procedure. I also E-mailed mike@vintageaudiomanuals.com yesterday mid-day for details on purchasing a service manual but have not received a reply yet. Any input as I head down this unfamiliar path will be greatly appreciated. Thanks.
 
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Why do you need to replace the boards? They become crispy critters, but there's never been one I could not repair.

You don't need to rewrap, just cut the wires away (make sure you know which one goes where!) and then solder back on with the wire physically attached with one loop before you solder. If you don't want to restrip, unwrap a couple of turns before you snip.
 
PacificStereo,

Just finished removing the boards. Please see the attached pictures. I am a newbie but pretty sure my Relay PCB is history as it is cracked completely across and several traces have been compromised. It also has evidence of the "crispiness" that you referred to in and around the area of the 2SD234 TO-220s that are normally replaced in the SB.

The Power PCB has one corner completely broken off which includes one of the support mount slots that the mounting bracket fits into. There also seems to be some evidence of "crispiness" on this board as well. At this point I believe I need to find some donor boards or etch new boards. Anyway let me know what you think. Thanks for your input.
 

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Two more pics of the Power Board.
 

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