10-25-2013, 08:14 AM
Eric, as you mentioned, most of the high voltage replacement electrolytics sold today are not really rated for the amount of ripple they are subjected to in a vintage radio. The ripple current rating is the spec most important in choosing a cap, and most of the imported caps sold over the internet are not so rated.
I recently checked the power supply of a properly operating model 118 and found about 16V (around 50 V P-P as seen on a scope) of ripple across the input 8 uF filter cap and this level could be considered normal. This was a new replacement cap and was checked for capacitance and ESR before installing. The cap stays stone cold in operation.
The best way to check for AC on the cap as opposed to pulsating DC ripple would be to use an oscilloscope, but I don't believe PuhPow has access to one.
I recently checked the power supply of a properly operating model 118 and found about 16V (around 50 V P-P as seen on a scope) of ripple across the input 8 uF filter cap and this level could be considered normal. This was a new replacement cap and was checked for capacitance and ESR before installing. The cap stays stone cold in operation.
The best way to check for AC on the cap as opposed to pulsating DC ripple would be to use an oscilloscope, but I don't believe PuhPow has access to one.
