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

48-482 tuner "restring"
#1

I have a beautiful 48-482 left to me from my father. The tuning string has come off the pullys. It has worked great up until this point. I would really like to get it back operating again. Any suggestions?
#2

Hi Tkline and welcome!

Your set is the same model I have had since 1968. One of my first 'old' radios. When I used it, it played very well, and I logged many shortwave and AM stations on it.
I still have it, however I am not powering it up again until I change the original capacitors.

First off, you can find the schematic diagrams here, which include the dial cord stringing diagram.
http://www.nostalgiaair.org/Resources/637/M0013637.htm

Next, since the set was working well in the past, you would only need to replace the 'filter capacitors' first, then test to make sure your installation was correct.
Next you should replace the other smaller capacitors. You could leave the others alone, but soon you might need to replace one or more that are not working right, so it is best to do then while the chassis is out of the cabinet. The main 'filter capacitors' are in the power supply section of the set, and they filter your current that passes to the rest of your set. They are critical to have working right. You have heard a radio that has a hum in it? That's an indication that the filter caps have dried up and not working.

This is the reason, after 62+ years, the old 'caps' have dried out and usually don't work as they should. Even if a set works on it's old parts, you will be onb borrowed time before they fail. Sure, you could use the set, but if a filter cap fails, it can take out a transformer, speaker, or other hard to find part. "Recapping' is a good way to have a reliable and safe operating set for many more years.

I suspect that the tubes will be fine. If you have access to a tube tester, that will be on your list in the process.
Here are a couple of links I pass on to others new to the hobby that explains a little more about the caps.
http://www.philcoradio.com/tech/plugin.htm

http://antiqueradio.org/powerup.htm

Changing these parts is not hard, but it must be done carefully. Do you have any experience in soldering or electronic work?
I am not sure, Ron can fill us in, but there could be some rubber insulated wires under the chassis. If the insulation has rotted and showing bare spots, it must be replaced. We can help guide you with that if need be.

Lubing all moving parts, cleaning off all the dust that may be on the chassis, and using a little contact cleaner on the pushbutton assembly are part of the process. That will make for smooth control operation and static free pushbutton operation. Re-stringing the dial cord is not hard to do, and you can either buy dial cord, or some even use dacron fishing line (Not monofilament)

Lastly, some of those tube are of the Loktal type. These are used by many Philcos and were made to 'lock in' to their sockets. Unfortunately, they have a tendancy to get oxidized pins that must be cleaned off for good contact. Once cleaned they work just fine.
There is a method to take those tubes out , some don't know about. On the base of the tube, there is a little raised dimple. Gently rock the tube in the direction of that dinple back and forth toward you. It should come out easily.

I will stop here, but this gives you a little idea of how to properly get the radio going again so it will be safe and reliable.
If you are good at working on things, being careful and asking questions, you will have no problem in getting your radio playing like new. I am sure your father would be happy that you have restored it.

Take care,
Gary.
#3

Hi again,
Just a quick post I was going to show what is inside of those fiter caps. Your filters may be indise of a metal can, but the idea is the same.

This cap was actually "working' in the set. On borrowed timem failure was going to be "who knows when".

The caps are rolled with a paste substance that dries out even though the cap was sealed with resin.

You can see the dried out electrolyte, and then upon unrolling the cap, you can see how the foil deteriorated. That damage was not caused by unrolling. It was like eaten away. Needless to say, this cap was going to fail and soon.
I know there are some that believe in the 'if it ain't broke, dont fix it' adage. That may work for some things, but not caps IMHO.
After seeing this, I say, why take the chance? Why risk damage to a cherished set, just to save a dollar or two on a modern replacement?
For those like me who want the underside to look original on some sets, you can simply 'restuff' the old capacitor tube with new parts, then seal it up. I think that's what I did on this one. That way all the labelled Philco logo caps are retained.
I hope this shows a good reason why we should recap.
Take care, Gary/

[Image: http://antiqueradios.com/gallery/d/13254...sect+1.JPG]

[Image: http://antiqueradios.com/gallery/d/13254...sect+2.JPG]

[Image: http://antiqueradios.com/gallery/d/13254...sect+3.JPG]
#4

Thank you Gary for all of the info. I really would like to get this radio working again. I t provided me with years of enjoyment when I was a child and tuning into the SW from all over the world. Nice to see there are a lot of people out there with so much respect for the older radios. After I get this one up to snuff, I have another older one that needs a lot of TLC.

Thanx again,
Ty
#5

No problem Ty,
I didn't realize I wrote a small novel, but hope the info helps.

I know what you mean about those old sets we remember from our childhood. When I was about 6 I remember mom had an old radio phono in the bottom of the closet that she would turn on when it was my bedtime. When she left the room, I'd sneak up on the set, and peer into the rear where the tubes filaments would be glowing. I even remember the smell that thing would give off.
Later in the night, I'd wake up and hear that the station had gone off the air and only far away stations would be trying to come in. That would lull me back to sleep.
Perhaps it is that memory that made me interested in radios.

With the guys here helping, I am sure you will be able to get your set going again.
Take care,
Gary.
#6

My parents had a Philco Radiobar which I used to play with when I was 5-7 years old. I got my first shock putting my finger in the bar light socket and being a mischievous child I poked holes in the speaker accessing it through the little door in the cabinet side. I remember the rectifier mounted on top of the transformer going gassy and flashing a brilliant purple. My grandma also had a Philco model 70 which had a torn grille cloth. The little spiral thing in the center of the speaker fascinated me. Wish I had that radiobar today.

Steve D




Users browsing this thread: 1 Guest(s)
[-]
Recent Posts
Jackson 715 not working
Now that you posted the schematic, I don't know why that Sprague electrolytic cap is across the meter, as it is not indi...MrFixr55 — 05:51 PM
HiFi (Chifi) tube amp build - but my own design.
What may be lacking in the PP Tube amps may be the 2nd harmonics, which some, especially RCA back in the day called &quo...MrFixr55 — 05:32 PM
Jackson 715 not working
Usually in an emission tester, the tube under test is measured as if it were a diode. So, some testers connect all the g...RodB — 04:17 PM
Restoring Philco 37-604C
Yep. F5 is green, D5 is Red. Red is Bad. Green is Clean.morzh — 01:30 PM
Jackson 715 not working
I did start to do that but I stalled out because I could not figure out how the grid and plate get voltage. In this diag...daveone23 — 11:52 AM
Restoring Philco 37-604C
(Insert Homer Simpson "DOPF" Here.) When all fails, look at the can. Took the Ron Ramirez advice, red Caig D...MrFixr55 — 09:23 AM
Philco 91 Speaker Replacement
From your text I am not sure if you intend to use the existing speaker with a resistor instead of the field coil. It wo...morzh — 08:44 AM
Philco 91 Speaker Replacement
My field coil is bad. I am still hoping to find an original, but if I can't I will go with a fitting Philco speaker, 125...dconant — 08:34 AM
Philco 91 Speaker Replacement
As Rod said, it is OK to use a fitting speaker, and then look for an original one. If you buy a Hammond 125 output tr...morzh — 08:15 AM
Philco 91 Speaker Replacement
Yes, I often have to substitute, then keep an eye out for an original. In the meantime, the radio is working and being e...RodB — 08:02 AM

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

>