The last 2 6 volters still have hash or buzzing even after replacement of all capacitors. The 1936 Ford and 1950 Chevy have background buzzing. The 1953 Chevy does not have any at all. What can be done?

Hi

Is the noise mechanical or electrical? Vibrators make mechanical noise. Some more than others.

Car radios have electrical noise that's harder to filter due to wave form. Vibrators produce a square rather than sine wave. Has the buffer cap been replaced? Other capacitors on the battery line? Be sure replacement caps ground to original connection points in the radio.

Norm

:The last 2 6 volters still have hash or buzzing even after replacement of all capacitors. The 1936 Ford and 1950 Chevy have background buzzing. The 1953 Chevy does not have any at all. What can be done?

I used a solid state vibrator to replace the mechanical (which still worked). Also put in buffer capacitor and 10/450 caps and others. But cannot get to the battery caps going in. Thanks.

Should be able to find noise using a scope? A solid state vibrator might be better with a slightly different value buffer cap? You should be able to see spikes generated by the vibrator. Try different buffer caps for lowest spikes without reducing voltage. Bypass other caps to see if they make a difference on the scope?

Try a .1 mf across electrolytics. May sound strange but .1 mf caps are better preventing high frequency interference than electolytics. Noise in car radios is caused by fast switching spikes.

Norm

:I used a solid state vibrator to replace the mechanical (which still worked). Also put in buffer capacitor and 10/450 caps and others. But cannot get to the battery caps going in. Thanks.

I will try .1 mf across the positve sides of the e caps. I do not have scope. So must use trial and error.