Packard Forum Index » Post-War (1946-54)

Anyone recapped a radio? I am considering it as opposed to sending it off.

Not yet, but I am also considering it on The radio from my 53. First step is to get a schematic that has all The caps you need listed, then you have to choose new caps that meet or exceed (but not too much) the cap and volt spec of The originals. I am tentative about taking on The task, and it might be a little nuts, but sure would be cool if it works. There are also People that restore home Radios as a hobby, so it cant be rocket Science. A friend of mine restores old pinball machines, and it is similar work. He volunteereed to help me pick out The caps. I don't know if there is an Easy. Source to get all The caps in one shot.
I am interested to see what we hear on this. On The other Hand, soldering out/in 10 to 15 caps is one thing, but troubleshooting if it needs more work could require some in depth Research.

You are in the same dilemma I am in-justradios.com sells the capacitors-~ $17 for the caps in a 47 radio. Strange you mention pin ball machines-my son repairs them!! He sends the electronics out for repair however. I found a schematic for my radio on this web site-not great but readable.

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Did you go thru the schematics to determine exactly what to order and arrive at that price or did they do it and suggest specific items in a kit. All I see on their site is their general order large volume supply type kits

I went thru the schematic that I found on this web site and made a list of cap's(24). I them went to their price list and added them up. Most are .05mfd(filter cap) or in that range. I am in the undecided phase as whether to tackle this or send it out. I may wait until I actually get it out to decide. One thing-the radio has a couple of wires running across the bottom

David

Those radios are standard household super heterodyne receivers modified for 6 volts via the 60hz vibrator.

The resistors can also open, but if there are no symptoms of the need for repair - fading or static after warm up, excessive hum, poor reception, poor amplification, etc, etc, then the best repair is to purchase parts and put them in a cigar box.

I remember solid state oscillators being made which is a worthwhile purchase.

Also, if the coils open the unit will need to be realigned using an oscilloscope.

Because the units are not rectifying household current the filter capacitors have a longer life. However, old capacitors don't damage any part of the radio if they are drying out.

The biggest problem with radios is there is nothing but junk on the airwaves.

Thanks. I'm also in the same spot with the same quandary. Do we have the same PA382042 radio? I count more than 24 caps -- although I think there's a couple that may not need to change so maybe the same count.

IMO, changing caps is not in itself a big deal as long as you have decent soldering equipment. I believe there have been one or two DIY guys doing it on different year radios. Don't remember hearing of any problems -- but there is always the unlucky draw.

The thing I'm concerned about and reason for leaning toward sending it away is if the value of something old was off or the new changes something enough to throw the IF alignment out. That could cause an issue and without the signal generator and proper test equipment, it might need to be sent off anyway to get back to first class -- or even a working condition.

Are the wires actually fastened to the bottom of radio or are they the courtesy light loom and can be pushed aside?

I think I have the PA382042-it appears to be the same as in the manual found on this site. I may have missed a couple of caps but it is close to that number. You are correct and that is my concern also that there is something else and will require more knowledge than I have. If you deal with these things everyday it is easy. I also donot have a power source other that the car/no scope. I may talk myself into sending off.

I got an Email from a friend of mine who recapped The Radio in his 52 200 himself with success. He got The caps from canada, so I guess from justradios. I will try and get some more Info from him about how much work it was.
Also, only the paper or electrolytic caps dry out. The mica? And ceramic caps don't need to be replaced, which might bring your count of 27 down a few. My Radio has 21 listed total, now I need to figure out which ones are paper or electrolytic.

If you want to screw around with the radio then why not first acquire an understanding of what this information means and is supposed to be used for?

Radio people will tell you those old Philco's are good radios.

There is a voltage chart that can be used to diagnose specific symptoms. For example, the rectified voltage is 245V DC. Thus, if you want to test the condition of the filter capacitors then connect an oscilloscope and look at the wave form. If it has lots of ripple there is a problem in the filter (this will be accompanied by excessive speaker hash).

All the capacitors before the vibrator are ignition RFI filters and also filter voltage back feed from the vibrator.

The alignment is used for the super-heterodyne internal frequency. The sections in the schematic are IF, detector, Mixer, rectifier, amplifier. The amplifier is a push-pull type which is high quality.

If the parts in the radio are good, chances are what is replaced will not be of as high quality as what has been thrown in the trash.

So about the only argument for blindly replacing those parts to preserve them for posterity?