Re: 575 restoration


Mark Vincent
 

Paul,

Increasing C811 will not hurt. Higher capacitance will reduce the noise at that circuit. I mentioned Orange Drops since those are well known. The ones you have in stock are fine. Replacing an axial to radial is fine. What John said is correct about noise sources! Invest in a Isobar power strip. Those are worth the cost. A shielded power cord will also help.

If you replace any of the electrolytics, use Nichcion LGR, LGZ (for 82mfd or larger 450V), ULD, UCY or UHE. These are low ESR which filter high frequency noise better than the originals or new general purpose electrolytics either 85 or 105C that are not low ESR. These ones I listed are also long life, 5000-20000 hours. Adding a ,01mfd 1kV ceramic across electrolytics will help with noise reduction. A Corcom line filter may be needed underside if the noise is still there. I would mount it as to not drill any holes to keep the piece original. This type would be with flying leads on each end.

You can change the light source if that is a noise generator. Using a lamp with a filament will not generate noise, e.g. carbon filament, tungsten or halogen. A small VARIAC can be used to dim the lamp when desired. That will be a linear way that does not generate noise like a standard triac lamp/motor dimmer.

Mark

Mark

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