Welcome Guest! Be sure you know and follow the Phorum Rules before posting. Thank you and Enjoy! (January 12) x

Thread Closed
Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

ANTIQUE 1928 AMERICAN BOSCH CONSOLE CABINET RADIO 48AA
#2

That American Bosch is a GREAT old radio ! Do NOT try to power it up until you have pulled the chassis and checked to see that all paper condensers and electrolytic condensers have been replaced, all the resistors checked to make sure they are in spec, and replaced if necessary. Then test all the tubes and replace those which are bad or weak. Once that is done, then you can power it up on a variac. If you are very sure of your work you could even just plug it in and see what happens being careful to feel the power transformer and watch the plates of the rectifier tube for overheating, which is what I mostly do, though not the recommended approach.

Now, you may wonder why we replace ALL the paper condensers and electrolytic condensers. It is because they are either bad already, or soon will be, and they can fail in a shorted condition which can cause damage to things like the power transformer which is VERY EXPENSIVE to get rewound, if you can even get it done. They can also cause a fire hazard. Best to just replace them all and be done with it.

Looking at the schematic   http://www.nostalgiaair.org/Resources/773/M0040773.htm   I see that there are a couple of condensers across the power input to ground to filter out line noise. This was VERY common on these old sets, Philco, RCA, Zenith and others did the same. These should be replaced with a type Y safety condenser, the kind that FAIL OPEN.

I envy you this latest acquisition. It is going to be a great project, and you will both learn a lot and have a lot of fun. Be very patient. Take your time. You will end up with a fine, reliable radio you can be proud of, and which will still be working fine years and years from now. I look forward to your thread detailing your progress in the restoration.

As for that, TAKE LOTS OF PICTURES ! It is so much easier now that we have cheap digital cameras. Take them before you start ANY work so you have a record of how things were to begin with. Then take more pictures along and along as you work, documenting each thing you do. You'll find this can be invaluable if you want to check things. Also, you will have pictures to post in your restoration thread. About posting pictures... If you first post them to a picture posting site, and then use the link to that photo to post the picture in your thread here, you will find that it will load much quicker when people check the thread.  You can use any of the picture posting sites. I use tumblr. Good luck, and feel free to ask any questions you may have.


Messages In This Thread
RE: ANTIQUE 1928 AMERICAN BOSCH CONSOLE CABINET RADIO 48AA - by mikethedruid - 08-04-2021, 02:14 AM



Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Need to purchase some accessories for restoration of my Old Philco Radio
Hi Paulo, Welcome to the Philco Phorum. I can see why you want to find good reproduction parts. That is a bea...MrFixr55 — 11:10 PM
HiFi (Chifi) tube amp build - but my own design.
Tim, I have some bakelite sockets in my work shop that I can dig up. I believe quite a few are NOS. I will take photo...RodB — 10:03 PM
Philco 610B oscillator wiring
> The cathode as noted is wired directly to the ground side of the heater filament for that tube, not to the #17 and ...Radioroslyn — 08:12 PM
HiFi (Chifi) tube amp build - but my own design.
Tim; I noticed your post a little late, but I would take one of the junk sockets and try to break a chunk out of it wi...Arran — 08:07 PM
Need to purchase some accessories for restoration of my Old Philco Radio
Here is a list of resources found in our online library that you might find useful. Mike's Gobs of Knobs email addres...klondike98 — 01:46 PM
First Radio restoration
Hi Tubeman, Welcome to the Philco Phorum.  Phamily Phriendly Pfun with Phine Pholks Phull of Philco Phacts. (See a p...MrFixr55 — 12:33 PM
First Radio restoration
You could post in the WANTED ADs section here on the Phorum and see if anyone has an RF generator that they want to sell...klondike98 — 11:55 AM
Zenith H725
Good ideas, thank you Arrange and Rich. I have the adhesive aluminum foil already and can try that immediately. More ...EdHolland — 10:18 AM
Graphics for majestic 1050 dial glass.
Murf; I found this thread on the ARF, the first photo has a pretty good view of the dial glass. Regards ArranArran — 01:12 AM
Zenith H725
hello Ed, how about that speacial tape used for ducting it's like foil or how about thin piece of aluminum roof flash...radiorich — 12:19 AM

[-]
Who's Online
There are currently no members online.

>