[Dave D]

Today I tackled the removal of the RF deck to replace three paper capacitors. I had previously replaced the 16mfd electrolytic mounted on the RF deck by adding a terminal strip under the chassis. Since I had the deck removed I decided to stuff the old electrolytic can with the new capacitor. To my suprise the old capacitor was filled with liquid. The part number is 30-2118S. I have stuffed many old cans but this was the first I have encountered filled with liquid. Can anyone enlighten me about this capacitor? I would also rather take a beating than have to remove that deck again.

Dave D

[exray]

Its a boric acid solution which is quite typical of the era. Not harmful or anything...just a pain when they leak all over everything.

[Dave D]

EXRAY, Thanks for letting me know what I got into. I was cutting the bottom off of the capacitor with a Dremel tool and I was very suprised when a clear liquid started leaking out. Had never seen that before. Have to give Philco credit for having an excellent seal as it didn't leak or dry out in seventy years.

Dave D

[exray]

I once made the mistake of using a torch to heat up a Mershon type of wet capacitor to remove the top cap that was pressed into place. Not the smartest thing I've ever done.

[Alan Douglas]

"Wet" electrolytics had the ability to stand high leakage current during warmup when the B+ would otherwise tend to soar above normal.

[Doug Houston]

My father bought a Philco 37-650 for Christmas 1936. It went about 2 years when the first filter condensers went bad (opened). It (or they) were replaced by dry electrolytics, and I never had known that the originals had been wet types. Right around that time, wet electrolytics were on their way out.

Cute tale: I worked in a radio shop in 1944, on the bench, and one of the guys told that he'd been on a service call in a home with a console set that had a tilted panel chassis. The chassis was mounted in the cabinet on an angle. As with many chassis designs, the filters were mounted along the back of the chassis. One or more of the filters on this set had heated up in a failing mode, and blew the top off the can. There was a big spray of juice up the wallpaper behind the set. I guess it scared the slats out of the owners!