09-06-2015, 08:27 PM
Yes, as Terry said electrolytics will not hold up long in this application.
Small value electrolytics are not rated for the ripple current they will be subjected to in a tube power supply filter. The lower the capacitance, the lower is their ripple current rating, and a modern 2 uF electrolytic was not designed to be an input filter in a vintage tube power supply. They will overheat and eventually fail.
Back when the 511 was designed, capacitors were expensive and so they used the smallest capacitance paper caps possible. These caps could however handle the ripple with no problem.
Today, the best option for replacement is a film type cap. They are designed to handle such service and will basically last forever. These are the type I use and have been very happy with their performance.
https://www.tubesandmore.com/products/C-FS-630
Small value electrolytics are not rated for the ripple current they will be subjected to in a tube power supply filter. The lower the capacitance, the lower is their ripple current rating, and a modern 2 uF electrolytic was not designed to be an input filter in a vintage tube power supply. They will overheat and eventually fail.
Back when the 511 was designed, capacitors were expensive and so they used the smallest capacitance paper caps possible. These caps could however handle the ripple with no problem.
Today, the best option for replacement is a film type cap. They are designed to handle such service and will basically last forever. These are the type I use and have been very happy with their performance.
https://www.tubesandmore.com/products/C-FS-630
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