I'm about as non-guru as they get- Also a "newbie", but I've read a few books and looked at a few good websites. There is a nice re-capping article at antiqueradio.org that addresses your questions (there are also a lot of restoration stories with pictures too). In general you'll find many opinions on what is optimum on re-capping.
A rule of thumb is that many of these old radios were designed for a +/- 20% tolerance on capacitors, so you'll be ok substituting a .047 for a .05. Some notice that many new cap's are slightly under value and look for slightly higher values when they shop- The cap's voltage rating is an insurance policy. You can replace a cap rated for 300 volts with one rated for 600 volts and you'll have a more robust circuit without changing performance.
Some people prefer to re-cap with "orange drop" capacitors from Antique Radio Supply (www.tubesandmore.com) or a host of many others. They even sell assortments of commonly used cap's all rated 600 V with various mFarad ratings. Also some like ceramic caps rated at 1000V.
For a more realistic restoration, some will place the new capacitors inside the old ones.
Sounds like you are on the right track. Good luck with your restoration, and make sure you post when it's all fixed up! I just got Grandma's old console fired up. A great feeling.
: I am replacing old paper capacitors in the output choke-condensor section of a Radiola 66. They are physically larger than I expected. One is around the size of a cigarette pack, but thinner. They are 1 mfd, 2mfd and 0.5 mfd. This section is around 300V.
: 1. What is the best type of capacitor to use here?
: 2. Also I can't seem to find 0.5 mfd. Closest I can get is 0.47. So how important is matching the farads. is 0.03 enough to worry about?
: 3. Same question for the voltage(assuming higher is better correct?)What if I pick a 1 mfd rated at 650 volts (for a 300 volt circuit) for expample.
: Any help would be appreciated.
: Thanks
: jeff
: Jeff,
: I'm about as non-guru as they get- Also a "newbie", but I've read a few books and looked at a few good websites. There is a nice re-capping article at antiqueradio.org that addresses your questions (there are also a lot of restoration stories with pictures too). In general you'll find many opinions on what is optimum on re-capping.
: A rule of thumb is that many of these old radios were designed for a +/- 20% tolerance on capacitors, so you'll be ok substituting a .047 for a .05. Some notice that many new cap's are slightly under value and look for slightly higher values when they shop- The cap's voltage rating is an insurance policy. You can replace a cap rated for 300 volts with one rated for 600 volts and you'll have a more robust circuit without changing performance.
: Some people prefer to re-cap with "orange drop" capacitors from Antique Radio Supply (www.tubesandmore.com) or a host of many others. They even sell assortments of commonly used cap's all rated 600 V with various mFarad ratings. Also some like ceramic caps rated at 1000V.
: For a more realistic restoration, some will place the new capacitors inside the old ones.
: Sounds like you are on the right track. Good luck with your restoration, and make sure you post when it's all fixed up! I just got Grandma's old console fired up. A great feeling.
:
: : I am replacing old paper capacitors in the output choke-condensor section of a Radiola 66. They are physically larger than I expected. One is around the size of a cigarette pack, but thinner. They are 1 mfd, 2mfd and 0.5 mfd. This section is around 300V.
: : 1. What is the best type of capacitor to use here?
: : 2. Also I can't seem to find 0.5 mfd. Closest I can get is 0.47. So how important is matching the farads. is 0.03 enough to worry about?
: : 3. Same question for the voltage(assuming higher is better correct?)What if I pick a 1 mfd rated at 650 volts (for a 300 volt circuit) for expample.
: : Any help would be appreciated.
: : Thanks
: : jeff