07-06-2013, 05:01 PM
Most Philco electrolytics that are across rectifiers and thus are exposed to the highest voltage and highest ripple current are rated 450V.
They are un fact a bit underrated as if you doo not load your rectifier the voltage acropss the ectrolytic cap may easily exceed the rated one by about 100V or so. However due to the fact that the rectiifier is a tube and the load is the tubes, they come up more or less at the same time and so the voltage across the cap is not exceeded, since as the rectifier starts to conduct so do other tubes.
So 450V is good enough and I use them.
Then again, when replacing the electrolytics, you can always read the values off them. Mine in 37-116, as well as in others, are original Philco caps and read 450V.
Last but not least: I recently wrote a thread about the ripple rating. To achieve a higher one I use lower voltage (such as 350V) double capacitance caps in series. As a result I achieve high ripple rating and as a bonus I have very high voltage rating. No matter what happens in that radio the voltage is not exceeding 700VDC. Kill two birds with one stone.
They are un fact a bit underrated as if you doo not load your rectifier the voltage acropss the ectrolytic cap may easily exceed the rated one by about 100V or so. However due to the fact that the rectiifier is a tube and the load is the tubes, they come up more or less at the same time and so the voltage across the cap is not exceeded, since as the rectifier starts to conduct so do other tubes.
So 450V is good enough and I use them.
Then again, when replacing the electrolytics, you can always read the values off them. Mine in 37-116, as well as in others, are original Philco caps and read 450V.
Last but not least: I recently wrote a thread about the ripple rating. To achieve a higher one I use lower voltage (such as 350V) double capacitance caps in series. As a result I achieve high ripple rating and as a bonus I have very high voltage rating. No matter what happens in that radio the voltage is not exceeding 700VDC. Kill two birds with one stone.
