[TenTec] [] Running a Century 21 on external 12V power

[Josh Gibbs]

This kind of capacitor:

http://s337.photobucket.com/user/jusepics/media/Tropical_Fish_Color_Chart.png.html
http://www.electrojumble.org/TropFish_a.jpg

>From my research, its a polyester film type. I noticed a couple of them are
cracked. Think its worth replacing them?

I'm about to try shielding the transformer with some thin steel sheet I
have on hand.

-Josh

On Fri, Jun 2, 2017 at 9:04 PM, Gary F <dukeshifi at comcast.net> wrote:

> Josh, I don't know what you mean by tropical fish capacitors but some
> capacitors are quite sensitive to noise pickup, as you describe, especially
> in high gain audio circuits like this one. This is the reason why some
> early capacitor designs were supposed  to be installed in a preferential
> direction-not because they were polarized but because they were fabricated
> in such a way that the last layer of the cap acted as a shield for the rest
> of the capacitor within.
>
>
> I doubt that changing those caps will resolve your hum. Jim and I agree (I
> think) that reducing magnetic coupling is your best shot at the hum problem
> resolution.
>
> Gary
>