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

89B Detector Coil Rewinding
#1

I've been going through my 89B Code 123 (No run stamp, It appears to be a late 89B with the 77 oscillator). I was able to fix the antenna coil. The detector coil, however, had a bad primary winding , and underneath has the green corrosion on the bottom of the secondary winding (center tap to ground) . The secondary is open from the center tap to ground. I fear that the oscillator coil is in the same condition, but I haven't removed it yet.

Has anybody rewound the secondary winding and recorded the turn count and wire gauge? How about the oscillator coil?

I appreciate your response. Knowing what I know now about the 89B, I would have looked at something else, but the cabinet is in decent shape, even the grille cloth is in good shape. I look at it as a challenge, now.


Attached Files Image(s)
       

Robert Kristelli
Brownsburg, Indiana
#2

On that second pic, might be able to re-wrap just the lower part of the winding (before taking it all off, worth a try - top 90% looks okay). Wrap a round of painter's tape just above the bad section to hold it, and solder in 34  awg after removing the bad wire, and wrap the new down into the feedback coil, check ohms, and if necessary, replace the 15 turns of the feedback - might get it back in order.
#3

https://philcoradio.com/library/index.ph...lco-coils/

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#4

Thanks for the info, everybody! I'm going to take a chance rewinding the bottom half of the secondary and the primary.

Robert Kristelli
Brownsburg, Indiana




Users browsing this thread:
[-]
Recent Posts
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum Martin. I count about 9 paper caps, the 3 electrolytic caps and 2-Y2 safety caps to replace th...RodB — 09:44 PM
Part numbers to model cross
Jim, We have this index put together by Dale Cook but I don't think that is quite what you are looking for. The Parts...klondike98 — 09:37 PM
Philco Model 38-7: what caps & resistors do fail typically?
Yep the dim bulb test is OK but I'd definitely replace all those electrolytics before I did it. Since those #47 conden...klondike98 — 09:18 PM
Philco 42-345 Restoration/Repair
The resistor is a 2.2 Meg, it was the last one I hadn't replaced. The broadcast is coming in after replacing it.osanders0311 — 09:09 PM
Philco 42-345 Restoration/Repair
What does the resistor measure? I think it should be 3.3 Meg. If the oscillator coil has continuity and the resistanc...RodB — 09:03 PM
Philco Model 38-7: what caps & resistors do fail typically?
Good idea to check the coils... then I'll get hold of an incadescent light bulb and see what happens when the unit is sw...Musaeum — 08:49 PM
Philco 42-345 Restoration/Repair
I have that same set, ain't too much shortwave I like anyway.....it is a good AM DX set. PaulPaul Philco322 — 08:32 PM
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum, Martin! Open a new thread in Philco Electronic Restoration when you begin working on your 38-7. ...GarySP — 08:28 PM
Philco Model 38-7: what caps & resistors do fail typically?
Welcome to the Phorum! :wave: Here's the schematic for that radio from our digital library: Something to do bef...klondike98 — 08:05 PM
Philco Model 38-7: what caps & resistors do fail typically?
Hi all, on vacation in Montreal,  a friend of mine showed me a Philco Model 38-7 console radio from the 30ies. Mechan...Musaeum — 07:21 PM

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

>