[radionoob]

Hi everyone,

I've been slowly looking at my 38-7 recently, and trying to learn electronics whilst I repair this old bird to sing again. I first replaced the power cord, because the old one was just plain dangerous. Now, I'm moving in to actually replacing parts (and I'm nervous about it, because other than some basic electrical safety knowledge, and VERY basic electronics knowledge, I've got nothing else to run with).

Today I noted that I have one of those canisters, which appears to be screwed. There is a crystal like substance coming out of the top and the bottom. I removed the can from the chassis, and am now wondering what to do.

Are there multiple capacitors inside this can? Should I cut it open? Is there anything special I should know while I try and fix this can?

Any input would be great, thanks.

[radiorich]

Hello radionoob ,
Well welcome to the site!.....
Well to start with is a Schematic diagram of that set and print you a copy
Because you'll need to get the right parts values and where they are localed before tearing it to the set

first thing is you'll want to make sure the powertrans is good before putting money into this set.


Anyways

First all you should have a couple of those caps mounted on your chassis
those Are your mainpowersupply fitercaps .
They are called electrolytics and just depends you can cut those two cans open and mount the newer repl ace caps inside since that are smaller nowdays.
just depends on your skills .
far as those two caps go one should be a 8ufd you can replace it with a modern 10 ufd and the other will be a 25 ufd you can replace it with a modern 22ufd cap make sure you get either a 160 volt or 250 volt cap to replace them with

sincerely Rich

[Jim Dutridge]

There should be 2 cans on this chassis. One is a single 25 MFD and the other is a 4 and 8 MFD capacitor.The 25 MFD cap has its negative tied to the center tap of the power transformer HV secondary while the negatives of the 4 and 8 MFD caps are tied to the chassis. Each can should be marked as to what value/values are inside.

You can use a 22 or 33 MFD to replace the 25 and a 4.7 and 10 to replace the 4 and 8 MFD respectively. All replacements should be rated at 450 volts. You can cut open the cans and install the replacements inside to preserve originality or just leave the cans alone, disconnect them and install the replacements underneath the chassis if theres room using a terminal strip. Hope this helps somewhat.

[radiorich]

Ya
Thanks jim for correcting me on the voltage I was still half wake

[radionoob]

Thanks a lot guys. After looking closely its the 25mfd can that is pooched. I've got it out now, and will do my best to replace it.