"The phone is a remarkably complex, simple device, and very rarely ever needs repairs, once you fix them." - Dan/Panther
Started by winkydink, January 08, 2009, 07:00:12 AM
QuoteGood morning Greg.I have finished the inspection of your radio. Unfortunately I have bad news for you. There are several major issues in both the power supply and RF/Audio sections. First - relative to the power supply, the ballast resistor (the one on the small separate chassis with the power cord and switch) is totally destroyed and is problematic as to a replacement. Second within the power supply chassis there is an open coil on one of the filter chokes. The power transformer is questionable but might be ok. There is an open high wattage power resistor. The wiring would need total replacement as the old rubber insulation is brittle and coming off most of the wires. Lastly, the filter capacitor block would need to be replaced with new capacitors.Second - in the RF section there was a catastrophic failure of one of the bypass capacitor blocks. Due to a short in the capacitors the tar inside the metal case melted and flowed outside the case in huge amounts. That most likely was the cause of the power supply failure. If that is the only problem these capacitors can be replaced with new. There is an issue with at least one of the RF transformers as it most likely is open. Often I can repair these, but not always. The others look ok but would need to be opened up to see for sure.So with all that I am thinking this radio needs too much to be salvageable. Because of that I would not like to take it on for restoration due to the complexity and costs associated. I can imagine your cost being well in excess of $300.00. And if I started on it and found the power transformer bad then that would be the end of it. I wouldn't know that until I got the other power supply issues fixed and then try the power supply with power on.There is a reasonable chance the RF/Audio section can be fixed however. But again I wouldn't know that without further testing.So I think it best if you just pick up the parts and do what you want with the radio. There is NO charge for my evaluation!!Again, sorry for the bad news but that sometimes is what happens with these very old sets.Bob
Quote from: Russ62 on August 29, 2014, 07:51:47 PMHello Brinybay, You should not dispose of the power supply to your radio as it is more restorable by an experienced collector/tech than you have been led to believe, and without a major portion of the chassis the radio is not particularly restorable. For example the ballast can be rebuilt with a series of power resistors mounted inside the old ballast shell. filter chokes are easily scrounged from old tube type tv and radio chassis that long time collectors often have stashed,value of chokes usually not too critical. Other resistors and capacitors are easy to find new or salvaged. Schematics to old radios are far easier to find than those to some phones, especially some early payphone variations. The cabinet to your radio looks very nice and that's the hard part. Since its as old as very collectible phones it would be a shame to junk an important part of the chassis making future restoration impractical. I don't take in repairs my self as I work full time as an electronic tech and barely have time to work on my own stuff, although I did live in Mt Vernon till age six. Perhaps in the future you could trade a few phones to another collector/tech in your area for repairs as they often collect both. russell, collector and repairer of early phones, radios and tvs since the 1970s.
QuoteOK, I have spent some time going over the RF section. Results: All the tubes are good. I have tested the RF coils and they are good. Two power resistors are good. Volume control is good. So it appears that everything but the capacitors are ok. But that's a 90% probability as there could be something else that I didn't find. So what I propose is to replace all the capacitors and then we will have to wait for a good power supply to see how the radio performs. The charge for all the capacitors in the RF section and my testing done in that unit will be $120.00. That's a minor risk on your part I think. No charge for checking the power supply, so far.I am going to bid on that ballast resistor (the one on ebay) and if we find another model 90 power supply then we can use it. If not then I'll just put it in my inventory for another time. So let me know if I should proceed.Bob-----Original Message----- From: craigslist reply 557fSent: Aug 29, 2014 9:27 AMSubject: Re: Antique Radio Restoration ServiceHi BobI would like to proceed with further testing on the RF section to see exactly what is wrong with it. So that there's no misunderstandings, I'm going to assume that this would be beyond your initial free visual inspection, and I'm ok with that. If there is nothing drastically wrong, please give me an estimate of what it would cost before proceeding with actual repairs. Provided everything goes well, like you said, I would at least have that part of it working, then we can concentrate on getting a proper power supply for it. If it goes the other way and the RF section is also toast, then I guess we'll stop there and I'll come get the parts. I would still need that RF section as part of the overall looks of the radioGreg ----- Original Message -----Sent: Friday, August 29, 2014 6:33:46 AMSubject: Re: Antique Radio Restoration Service As for the RF section, I think there is a good chance it can be made to work. We know of the capacitor can that shorted out and caused the mess of tar that leaked out, but that is the only visual problem I saw. I would be happy to check it out further, and then if nothing major shows up I could replace all the old capacitors in that section, test the tubes and give it a good overhaul. That way you would have at least that part in good order. It's your call on that.As for the power supply, I too see various power supplies for sale on eBay, and some of them might be usable in this radio. It's important to get all the correct voltages, so you need to know what you are buying for that. The most important voltages are for the tube filaments. The high voltages for the RF tubes are not as important to be exactly as produced by the original power supply. Actually I have a restored Stewart Warner power supply in excellent working condition that I considered telling you about. There is one issue with using it however, your radio calls for two separate 5 volt filament windings and my unit only has one. I think that might be a problem trying to make do with just one winding. If I were to get the RF section in working condition then I could try my power supply to see if it would work. Then another option would be to try and find a suitable original one on eBay. Incidentally I did see for sale on eBay an original model 90 ballast resistor for sale that is in good working condition. That is one of the issues your power supply has, so if you wanted to purchase that on the chance you can later find an original power supply box you would have that part already on hand. I think the price for the ballast resistor will be about $20. including shipping, unless it gets bid up which I doubt. The auction for that item ends in about 3-4 days. If interested I can give you the eBay item number.So lots to think about for you. Let me know how to proceed.
Quote from: Russ62 on August 30, 2014, 02:46:04 AMHello Brinybay, I wouldn't change to a different brand or model power supply. That would create a low value Frankenradio The original is perfectly repairable. Even a power transformer could be found if necessary. However replacing with the exact same power supply would be no big deal. Like the phones these sets were mass produced by the many thousands, and parts and chassis show up all the time at swapmeets radio collector forum classifieds and so on. However, I would probably be chased off a radio collectors forum as I don't do the total capacitor replacement they encourage now a days but repair to the component level like I've been doing for over 40 years to preserve originality, yet I have sets I repaired many years that still work fine.