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38-690 Electronic Restoration
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Well I finally had time to start restoring my prize. It did work and all functions and bands were good to start which is a blessing.

There are a lot of issues with this radio as someone did a mediocre job and just replaced caps. I found many bad resistors, one cap missed in the sub chassis, the bypass cap can was never replaced with new caps, and lots of poor solder connections.

So far I have rebuilt the Power Supply/Amp chassis. All but one filter can were re-stuffed with 630V film caps. The biggest one would not fit inside the 18 uF can so it is under the chassis. The chassis had to be repainted because there was too much rust for my liking. I tested the chassis with the radio before I moved on to the rest so I would not have it to worry about unknown problems later on.

The sub chassis has been removed and stripped down for painting. I have changed all of the bad components already. Before I did this, I took pictures of how the dial assembly came apart and wrote a tutorial so I can put it together working backwards from my notes.

I also have the main chassis ready for painting. I haven't done much electronically with it yet, except to rebuild the lamp sockets, repair the on/off switch, and re-stuff the can cap with 630V film units.

I'm taking my time and marking off what I've done on the schematic. Also, there are notes about anything I found suspicious from the last guy.  

Here are some pictures of the process so far. I know there will be some questions I will need answered as I progress.

https://www.flickr.com/photos/152428891@...ed-public/


Messages In This Thread
38-690 Electronic Restoration - by tbone - 11-08-2017, 08:49 AM
RE: 38-690 Electronic Restoration - by morzh - 11-08-2017, 09:30 AM
RE: 38-690 Electronic Restoration - by tbone - 11-08-2017, 03:32 PM
RE: 38-690 Electronic Restoration - by morzh - 11-08-2017, 03:52 PM
RE: 38-690 Electronic Restoration - by tbone - 12-10-2017, 04:29 PM
RE: 38-690 Electronic Restoration - by tbone - 12-10-2017, 05:31 PM
RE: 38-690 Electronic Restoration - by morzh - 12-10-2017, 06:10 PM
RE: 38-690 Electronic Restoration - by tbone - 12-10-2017, 07:04 PM
RE: 38-690 Electronic Restoration - by morzh - 12-10-2017, 07:33 PM
RE: 38-690 Electronic Restoration - by tbone - 12-10-2017, 09:57 PM
RE: 38-690 Electronic Restoration - by tbone - 12-11-2017, 01:16 PM
RE: 38-690 Electronic Restoration - by morzh - 12-13-2017, 10:59 PM
RE: 38-690 Electronic Restoration - by KCMike - 12-14-2017, 09:36 AM
RE: 38-690 Electronic Restoration - by morzh - 12-14-2017, 10:02 AM
RE: 38-690 Electronic Restoration - by tbone - 12-16-2017, 08:09 AM
RE: 38-690 Electronic Restoration - by tbone - 12-17-2017, 01:41 PM
RE: 38-690 Electronic Restoration - by tbone - 12-20-2017, 08:02 AM
RE: 38-690 Electronic Restoration - by tbone - 12-28-2017, 07:47 PM
RE: 38-690 Electronic Restoration - by morzh - 12-28-2017, 08:06 PM
RE: 38-690 Electronic Restoration - by tbone - 12-28-2017, 08:09 PM
RE: 38-690 Electronic Restoration - by morzh - 12-28-2017, 08:23 PM
RE: 38-690 Electronic Restoration - by tbone - 12-28-2017, 10:15 PM
RE: 38-690 Electronic Restoration - by tbone - 12-29-2017, 10:22 AM
RE: 38-690 Electronic Restoration - by morzh - 12-29-2017, 11:29 AM
RE: 38-690 Electronic Restoration - by tbone - 12-29-2017, 11:35 AM
RE: 38-690 Electronic Restoration - by morzh - 12-29-2017, 12:09 PM
RE: 38-690 Electronic Restoration - by tbone - 12-29-2017, 12:51 PM
RE: 38-690 Electronic Restoration - by tbone - 12-29-2017, 09:48 PM



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