The PHILCO Phorum

Hi,
I just started a restoration of a model 60 cathedral and came across a bakelite condenser 4989 Z. According to the schematic I have it is a .18 single but upon removing the wax there are two caps inside. I was on philco repair bench and a Z version is not on there for a 4989. I have 0.22uf caps can I use these and what pin is the double? Just want to be sure.

thanks
Chris

Hi

The 4989-Z has two .09 uF caps in parallel to make .18 uF. You will note there is an external jumper wire between the center terminal and the outermost terminal; the grounded terminal is common to both caps.

Yes, you can use a single 0.22 uF in place of the two, or two single 0.1 uF caps. Close enough for gubmint work, as they say.

Ron,
Thanks for the information. I do have two 0.1 caps. Good thing I asked I was going to use two 0.22 caps. It was not labeled as a double condenser on the schematic I have. Is this typical? Which pin is the ground pin?

thanks
Chris

The screw hole is the ground in that particular block.

Ron,
Thanks for the information.

Chris