Replacement electrolytics
Dave wrote:
I have just re-capped the power supply capacitors in a DX-40 with 40uf
450 VDC Aluminum Electrolytics from NTE Electronics in New Jersey.
I have noticeable hum on the carrier. Measuring the ripple voltage with
a 10 Megohm ac coupled meter shows 2.3+ volts [average/rms ...
non-sinusoidal] on the 600 vdc line and 1.2 volts [average/rms ...
non-sinusoidal] on the 300 vdc line.
It appears the RS of the capacitors is way too high.
Your ripple values look ok to me. They calculate out to
be under 1%. (0.4% rms)
You probably have a problem elsewhere, such as a heater-cathode
leak, or short.
-Chuck
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