I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K

:I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K

First thing comes to mind is something wrong with the radio in the first place. Was it working before ? ..

What type of capacitor did you use? It should be a film cap, not an electrolytic cap. And, it should be AC rated, or if DC rated, at least twice the peak AC voltage across it (2 x voltage drop x 1.414).

A capacitor won't get hot (unless it is leaking). That's the beauty of using a cap for voltage dropping.
Doug

::I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K
:

Yes you must use NON polarized caps rated for AC

If it IS non-polar and it has a DC rating on it you must re-rate the 40%-50%

So a 600vdc rating will be suitable for 300-360vAC

I've had good luck using speaker crossover caps for "curtain burner" substitutes. The ones I've used are Solen brand, dual-rated 330VAC/630VDC: http://www.hndme.com/productcart/pc/viewCategories.asp?idCategory=113

Parts Express has them too, but it seems that theirs are rated 400VDC, which might be OK, but marginal: http://www.parts-express.com/crossover-capacitor-index.cfm?searchFilter=capacitor&CFID=4877948&CFTOKEN=61132737

I thought I had bought the higher voltage Solens from Parts Express, but it seems that they just carry the 400-VDC ones now.

I don't know why the number of tubes in the radio would make a difference. With fewer tubes, the voltage drop across the cap might have to be higher, but that shouldn't be a problem with the 330VAC/630VDC Solens.
Doug

::I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K
:
: First thing comes to mind is something wrong with the radio in the first place. Was it working before ? ..

:::I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K
::
:: First thing comes to mind is something wrong with the radio in the first place. Was it working before ? ..

yes, it worked fine, and still will wourk when I use a nicrome wire of the same omage as the old cord (300 ohms, I think).

Depending on what tubes are there and what the heater voltages are, you may be able to use a step down transformer of some sorts, too.

:I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K

:Depending on what tubes are there and what the heater voltages are, you may be able to use a step down transformer of some sorts, too.
:
::I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K

Thank you to all who responded. It is much appreciated. I had been using non-polar DC caps, before. I'll try the AC rated ones, and see if that works. The radio does work when I use a length of nicrome wire of the same ohmage (300 ohms, I think); but there you get the same problem with the heat. I'm hoping to use a cap, to eliminate that problem. Thanks --K

:Depending on what tubes are there and what the heater voltages are, you may be able to use a step down transformer of some sorts, too.
:
::I have an old three tube International radio that has a resistence line cord. I wanted to replace it with the capacitor, like the article on this site describes, with the 4 tube sets. It would not work for me. The capacitor kept overheating. Any suggestions? --K

Stephen: When you use a step-down transformer, do you just wire that between the new cord and the tube, then place a cap over that hook-up? Great idea, but I may not be able to do that since there is no room on or under the chasis to mount that. This is one of the very samll compact sets from the mid-late 30s. --K