01-22-2008, 11:16 PM
Many times resistors are very out of tolerance, usually high. I measure all the resistors with one lead de-soldered so other components are clearly out of the circuit. If they are more than 10% or so out of tolerance I replace them.
I think other people use 20% as the limit for resistors. I'm not sure how much it matters whether you use 10% or 20% as the limit, because I have taken resistors that were 200% or 300% high out of old radios that seemed to be working fine. I hope others will weigh in with opinions on this as I am really not sure what is the best approach. Possibly a resistor that has gone out of tolerance will continue getting worse.
Some resistors are exactly the right value after 50 years, but others have changed a lot. In the radio I am recapping now, a 42-350, almost every resistor is 20% or more high, so I am replacing almost all of them. This one will definitely not look original inside when I am finished.
A question on recapping for the more experienced restorers: how many of you re-stuff the wax/paper capacitors? Do any of you consider it essential for authenticity?
I always re-stuff the bakelite caps. They are a snap. It isn't a snap to re-stuff all the metal 'lytics on the top side of the chassis, but I do it whenever possible. Sometimes 3 or 4 modern lytics won't fit in the can. On my current project I re-stuffed both of the cardboard-bodied 'lytics even though they don't show. I haven't yet started to re-stuff the wax/paper capacitors. I put all of them in a big box, though, just in case I develop a passion for absolute authenticity someday.
I think other people use 20% as the limit for resistors. I'm not sure how much it matters whether you use 10% or 20% as the limit, because I have taken resistors that were 200% or 300% high out of old radios that seemed to be working fine. I hope others will weigh in with opinions on this as I am really not sure what is the best approach. Possibly a resistor that has gone out of tolerance will continue getting worse.
Some resistors are exactly the right value after 50 years, but others have changed a lot. In the radio I am recapping now, a 42-350, almost every resistor is 20% or more high, so I am replacing almost all of them. This one will definitely not look original inside when I am finished.
A question on recapping for the more experienced restorers: how many of you re-stuff the wax/paper capacitors? Do any of you consider it essential for authenticity?
I always re-stuff the bakelite caps. They are a snap. It isn't a snap to re-stuff all the metal 'lytics on the top side of the chassis, but I do it whenever possible. Sometimes 3 or 4 modern lytics won't fit in the can. On my current project I re-stuffed both of the cardboard-bodied 'lytics even though they don't show. I haven't yet started to re-stuff the wax/paper capacitors. I put all of them in a big box, though, just in case I develop a passion for absolute authenticity someday.
John Honeycutt