I've got a model 52 Grigsby Grunow with two OEM condensor banks mounted in steel boxes (1) 6"X4" and (1) 4"x3". I would like to mount new electrolytics in the cans and also get rid of some of the weight they add. What's the best method to melt out the tar/wax composition in these cans? Or, would it be better (and easier) to just re-route the ecaps somewhere in the wiring compartments? Any ideas/opinions would certainly be welcome. Thanks.

Allan

It certainly is easier to just mount new units under the chassis, but it takes a lot away from the aesthetics of the original wiring.

I've never opened up my boxes. The original power supply was missing in my 180, and the remaining condenser boxes in the radio chassis itself are a bit down the line from the power supply, so I'm not too worried about them. None of them have any leakage at all, which is amazing after almost 80 years.

If the boxes contain tar or wax, you can try soaking them in gasoline or mineral spirits. Another method would be to heat them with a heat gun or oven. Be careful not to start fires. Heat only enough to melt the substance (probably 150 degrees or less.....no more than 200).

The original condensers were not electrolytic. For the power supply filters you can use 20 MFD electrolytics, or you can go with original values, either electrolytic or non-electrolytic. If you go with larger value condensers, omit the .09 MFD condenser across the choke. The original power supply, due to the low capacitances available in reasonable sizes, utilized a tuned filter. If you go with original values you must continue to use the tuned filter system. You must also keep the .09 MFD condenser as close to .09 MFD as possible. Using random values may throw off the tuning of the filter and make it less effective. Two modern .047 MFD caps in parallel will give you .094 MFD, which might work. Otherwise use, in parallel, a .047 MFD cap, 4 .01 MFD caps, and a .002 or .003 MFD cap, whichever you can find.

T.