11-12-2008, 11:10 PM
Hi and welcome!
While the original electrolytics were 6 uF, this is no longer a standard value. You may use 10 uF, 450V electrolytics to replace the 6 uF units with no problems. Disconnect the original cans as Richard stated.
Be sure you watch polarity on these! If you look at the schematic on my website:
http://www.philcoradio.com/tech/images/90b.jpg
you will see that I have marked the positive ends for you.
In addition, note that while the negative lead of the output electrolytic (57) goes to chassis ground, the negative lead of the input electrolytic (56) goes to B-, not chassis ground. If you ground this lead, you will definitely have hum issues.
I suggest that a barely perceptible hum is acceptable; anything more indicates a problem.
While the original electrolytics were 6 uF, this is no longer a standard value. You may use 10 uF, 450V electrolytics to replace the 6 uF units with no problems. Disconnect the original cans as Richard stated.
Be sure you watch polarity on these! If you look at the schematic on my website:
http://www.philcoradio.com/tech/images/90b.jpg
you will see that I have marked the positive ends for you.
In addition, note that while the negative lead of the output electrolytic (57) goes to chassis ground, the negative lead of the input electrolytic (56) goes to B-, not chassis ground. If you ground this lead, you will definitely have hum issues.
I suggest that a barely perceptible hum is acceptable; anything more indicates a problem.
--
Ron Ramirez
Ferdinand IN
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