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Argus25 · 6th Feb 2018, 4:16 am

It would be interesting to know if this arrangement was selected to exactly cancel the ripple, or partially (under) cancel it.

The fact that a specific value like 0.75uF was used suggest it was carefully set up for optimal hum cancellation.

The implication is that; then would become critical that the dual filter electrolytic capacitor had both the same uF value as the original, and about the same ESR. So if the hum cancelling network is retained, one should bear this in mind when rebuilding the dual electrolytic, to make the uF value as close to the original as possible for the two sections.

6th Feb 2018, 4:16 am	#16
Argus25 No Longer a Member Join Date: Oct 2016 Location: Maroochydore, Queensland, Australia. Posts: 2,679	Re: Bush TV22 restoration It would be interesting to know if this arrangement was selected to exactly cancel the ripple, or partially (under) cancel it. The fact that a specific value like 0.75uF was used suggest it was carefully set up for optimal hum cancellation. The implication is that; then would become critical that the dual filter electrolytic capacitor had both the same uF value as the original, and about the same ESR. So if the hum cancelling network is retained, one should bear this in mind when rebuilding the dual electrolytic, to make the uF value as close to the original as possible for the two sections.