12-26-2006, 09:29 AM
I found a 41-280 with a near mint unrestrored wood cabinet on eBay in November of 2006. The dial face and push buttons had shrunk and looked terrible. This was probably why no one bid. After confirming that re-production parts where available I bid and won the radio for $25. After I got it home and poked around the chassis I decided to power up. The power cord was so dried out that it literally turned to dust when you bent it. I used a temporary plug and wire.
I have been fiddling around with old vacuum tube equipment long enough to know what happens when you slam it with full power after its been sitting for years, so a few years back I built a bench test power supply that uses the power limiting feature of a light bulb in series, a variable transformer, in-line fuse, GFI receptacle, ammeter and a voltmeter.
Many times as you begin to dial in power with the variac the bulb goes bright. That's when I am thankful I built this gadget. I've never done any damage to a set even if there is a catastrophic failure so long as you stop there.
Back to this 41-280. I powered up to about 25 volts and looked and sniffed, then 50 volts, 75 and 100. After a while I heard some audio, I tuned in a local strong station and it came in so load and clear that I had to turn the volume down.
This radio is 100% un-restored except for a tube I replaced later on and maybe one that someone else did years back. I can't explain it. I haven't recapped yet so when we listened to Christmas music over the holidays it was through said bench power supply in the bulb safety mode.
I get no AC hum, no tuning static, no scratch in the volume and only a slight inconsistency in the middle of tone control range. I even get reception on short wave with the built in antenna.
I suppose the environment in which this radio has lived all these years must have been perfect for wax and paper caps and some how the electrolytic caps didn't un-form. Again, a total mystery.
I've purchased all of the replacement caps and will do the swap eventually but continue to enjoy listening to this grand old lady in her 65 year old original glory.
Chris[/i]
I have been fiddling around with old vacuum tube equipment long enough to know what happens when you slam it with full power after its been sitting for years, so a few years back I built a bench test power supply that uses the power limiting feature of a light bulb in series, a variable transformer, in-line fuse, GFI receptacle, ammeter and a voltmeter.
Many times as you begin to dial in power with the variac the bulb goes bright. That's when I am thankful I built this gadget. I've never done any damage to a set even if there is a catastrophic failure so long as you stop there.
Back to this 41-280. I powered up to about 25 volts and looked and sniffed, then 50 volts, 75 and 100. After a while I heard some audio, I tuned in a local strong station and it came in so load and clear that I had to turn the volume down.
This radio is 100% un-restored except for a tube I replaced later on and maybe one that someone else did years back. I can't explain it. I haven't recapped yet so when we listened to Christmas music over the holidays it was through said bench power supply in the bulb safety mode.
I get no AC hum, no tuning static, no scratch in the volume and only a slight inconsistency in the middle of tone control range. I even get reception on short wave with the built in antenna.
I suppose the environment in which this radio has lived all these years must have been perfect for wax and paper caps and some how the electrolytic caps didn't un-form. Again, a total mystery.
I've purchased all of the replacement caps and will do the swap eventually but continue to enjoy listening to this grand old lady in her 65 year old original glory.
Chris[/i]
