01-13-2017, 09:22 AM
Arran
yes, this is what I ended up doing; ordered an excess number of caps from Mouser. Good caps are expensive, I ordered the Vishay with 630VDC/220VAC rating tubular, this one:
http://www.mouser.com/Search/ProductDeta...1813410635
and it is $1.28/pc.
I am sure there are cheaper ones but not from Mouser. Another plus of these: they are large and come with sturdy long leads which helps. As for those caps some suppliers sell, no-name or names unknown to me, I simply do not trust.
As for the twist lock, like I wrote above, found corrosion inside as it was not reforming well. You can always tell by how the reforming current behaves, whether the cap is improving or not. I restuffed it and I did not quite follow the values as from the sch the 5uF can be replaced with 12uF, 15uF 450V - with 20uF (it is not the first rectifier filter cap so the value is not critical if it is larger), and the 15uF 250V - also can be 12uF without any ill effects.
The first 30uF rectifier cap - I found two solutions, the Nichicon high ripple cap that provides about 500mA ripple, which is not bad, and then I decided to go with two 68uF caps in series that will afford almost 800mA ripple. I hope they fit in the can, I think they should. I almost always do this when restuffing the first cap in all my larger radios; with smaller ones I use a single high ripple cap solution. I use full voltage rating or close on each cap: this gives me two advantages: 1) no leakage equalizing resistors needed, and 2) higher voltage dictates higher ripple rating.
Basically if the old rectifiers did not rely on the capacitance size to determine the magnitude of the output voltage and the rectifier tubes itself did not limit the output cap size, I would simply use 100uF high ripple across the board, those have more than enough ripple rating, but unfortunately it s not the case and one has to be crafty with these to balance between the size, ripple rating and the needed capacitance, as today's caps simply smaller than those from the days of yore.
yes, this is what I ended up doing; ordered an excess number of caps from Mouser. Good caps are expensive, I ordered the Vishay with 630VDC/220VAC rating tubular, this one:
http://www.mouser.com/Search/ProductDeta...1813410635
and it is $1.28/pc.
I am sure there are cheaper ones but not from Mouser. Another plus of these: they are large and come with sturdy long leads which helps. As for those caps some suppliers sell, no-name or names unknown to me, I simply do not trust.
As for the twist lock, like I wrote above, found corrosion inside as it was not reforming well. You can always tell by how the reforming current behaves, whether the cap is improving or not. I restuffed it and I did not quite follow the values as from the sch the 5uF can be replaced with 12uF, 15uF 450V - with 20uF (it is not the first rectifier filter cap so the value is not critical if it is larger), and the 15uF 250V - also can be 12uF without any ill effects.
The first 30uF rectifier cap - I found two solutions, the Nichicon high ripple cap that provides about 500mA ripple, which is not bad, and then I decided to go with two 68uF caps in series that will afford almost 800mA ripple. I hope they fit in the can, I think they should. I almost always do this when restuffing the first cap in all my larger radios; with smaller ones I use a single high ripple cap solution. I use full voltage rating or close on each cap: this gives me two advantages: 1) no leakage equalizing resistors needed, and 2) higher voltage dictates higher ripple rating.
Basically if the old rectifiers did not rely on the capacitance size to determine the magnitude of the output voltage and the rectifier tubes itself did not limit the output cap size, I would simply use 100uF high ripple across the board, those have more than enough ripple rating, but unfortunately it s not the case and one has to be crafty with these to balance between the size, ripple rating and the needed capacitance, as today's caps simply smaller than those from the days of yore.
People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.
