08-30-2009, 05:54 PM
Well, a couple of hints:
Transformer: you can always unsolder all the leads, take the bells off, and take a good look. You could always slip some heat shring tubing (use the same color or you't go nuts later.) over the wire, but if it's really bad, you can usually strip back a couple of layers of wax paper and replace the wires where they are soldered to the windings themselves. The utmost caution, lest you break a fine secondary and don't have enough left to solder to. But mostly the transformer wires are pretty good, and if you get the heat shrink up into the bells, you don't have to disturb the transformer any more. If there are issues with a possible open winding, or overheating, of course this is another matter. Proceed with caution. You can also paint the bells while they are off, if you want to. Tape over all your new connections with several layers of electrical tape before re-assembly, Beware of any sharp points that may stick through and arc to the bells. Remember to put the cardboard shims back in, if there were any. Besides electrical insulation, they help to minimize buzzing. Measure everything before and after connecting the primary connected to the line (preferably through a variac, and go slowly and carefully) before putting the transformer back in the set. That way, you, and the transformer, and the radio have a good chance of a long and happy life.
Desoldering - You can buy some desoldering wick, which is a roll of braided copper which will absorb excess solder. You have to tin the end a little bit first, then heat it and apply to the joint where the glob is. Once the glob is gone, you will be able to see how the remaining connections are wound, and pick them out.
I often wonder if the production workers of yesteryear were paid by the pound of solder they used. I can remember saving solder scraps when I was a kid, which were melted along with the .22 bullets from target practice by my Dad, and poured into little ingots that were used as sinkers when we went fishing. Now, that was a real long time ago. Funny how you remember those things. Well, we didn't have a lot, and nothing went to waste.
I also use just a small screwdriver to whack off melted globs of molten solder, or again, a dull old dental exlporer which you can get from your dentist or hygeniest for the asking. Sometimes I wiggle the end of the part I am to replace while the solder solidifies, and then I can see how it is wrapped, and many times unwind it neatly with diagonal cutters, nippers, or dikes, whatever you call them. Anyway keep track of where the pellets land, and get rid of them immediately, lest they make new unwanted circuits for you.
Fuse - you can always add a fuse, and it's a great idea. 1 amp for the little 5 tube sets, 2 amps for the larger ones. You can use an in-line type on the line cord if you don't want to otherwise disturb the originality of the set. That way it's 100% reversable.
Ordering capacitors: Take a look at the typical radio you like to work on, count out what the typical values are, multiply that by how many radios you think you will recap in a year, and you've got roughly your number. Add in what electrolytics and micas you think you may need, and you'll come up with an order of, let's say $60-$100. Then, fill in the middle values, ordering a few here and there to make sure you have a reasonable assortment, then do it. That way, the 6 or 7 bucks does not hurt as much.
Somebody please fill in, I'm out of time, the url for the very good source for caps in Canada, has excellent web site, good prices-------- Gotta go for now.
Good luck
I learn something every day from this forum, so I like to contribute as well.
Well, thats my 2 cents worth for today.
Transformer: you can always unsolder all the leads, take the bells off, and take a good look. You could always slip some heat shring tubing (use the same color or you't go nuts later.) over the wire, but if it's really bad, you can usually strip back a couple of layers of wax paper and replace the wires where they are soldered to the windings themselves. The utmost caution, lest you break a fine secondary and don't have enough left to solder to. But mostly the transformer wires are pretty good, and if you get the heat shrink up into the bells, you don't have to disturb the transformer any more. If there are issues with a possible open winding, or overheating, of course this is another matter. Proceed with caution. You can also paint the bells while they are off, if you want to. Tape over all your new connections with several layers of electrical tape before re-assembly, Beware of any sharp points that may stick through and arc to the bells. Remember to put the cardboard shims back in, if there were any. Besides electrical insulation, they help to minimize buzzing. Measure everything before and after connecting the primary connected to the line (preferably through a variac, and go slowly and carefully) before putting the transformer back in the set. That way, you, and the transformer, and the radio have a good chance of a long and happy life.
Desoldering - You can buy some desoldering wick, which is a roll of braided copper which will absorb excess solder. You have to tin the end a little bit first, then heat it and apply to the joint where the glob is. Once the glob is gone, you will be able to see how the remaining connections are wound, and pick them out.
I often wonder if the production workers of yesteryear were paid by the pound of solder they used. I can remember saving solder scraps when I was a kid, which were melted along with the .22 bullets from target practice by my Dad, and poured into little ingots that were used as sinkers when we went fishing. Now, that was a real long time ago. Funny how you remember those things. Well, we didn't have a lot, and nothing went to waste.
I also use just a small screwdriver to whack off melted globs of molten solder, or again, a dull old dental exlporer which you can get from your dentist or hygeniest for the asking. Sometimes I wiggle the end of the part I am to replace while the solder solidifies, and then I can see how it is wrapped, and many times unwind it neatly with diagonal cutters, nippers, or dikes, whatever you call them. Anyway keep track of where the pellets land, and get rid of them immediately, lest they make new unwanted circuits for you.
Fuse - you can always add a fuse, and it's a great idea. 1 amp for the little 5 tube sets, 2 amps for the larger ones. You can use an in-line type on the line cord if you don't want to otherwise disturb the originality of the set. That way it's 100% reversable.
Ordering capacitors: Take a look at the typical radio you like to work on, count out what the typical values are, multiply that by how many radios you think you will recap in a year, and you've got roughly your number. Add in what electrolytics and micas you think you may need, and you'll come up with an order of, let's say $60-$100. Then, fill in the middle values, ordering a few here and there to make sure you have a reasonable assortment, then do it. That way, the 6 or 7 bucks does not hurt as much.
Somebody please fill in, I'm out of time, the url for the very good source for caps in Canada, has excellent web site, good prices-------- Gotta go for now.
Good luck
I learn something every day from this forum, so I like to contribute as well.
Well, thats my 2 cents worth for today.
