Quick Tech Tip Silver Mica Disease Repair

[@leoparadis8036]

Thanks for the video. Great job. On a side note I've seen what I think is a similar contamination on modern smd components caused by SO2 on silver. I worked in a modern paper mill that used gaseous SO2 for bleaching the pulp. Older equipment was not affected but newer lead free devices became intermittent and failed. The SO2 would react with the silver layers and cause a insulation layer to form.

[@oldavguywholovesRCA]

Interesting!

[@paulswift700]

Yes that's how I do it as well. You can put the new caps across the outside terminals as well if you don't know there value then just use a small trimmer cap to resonate then on what ever the If frequency is the remove the cap measure the value and place with fixed value caps. I've done this in the past and it works out well. Good luck with your restoration. 73. Paul.

[@jimnewman5596]

Repairing these IF's for SMD is a pain for sure. Good video.

[@countryside8122]

Thinking it would be better to solder those to the bottom of the connectors after it is reinstalled. Just a thought. Excellent video thanks for showing us how.

[@radio-ged4626]

I've not had silver mica disease inside IF cans yet, but I have had a variable capacitor with it. I've only been repairing valve radios as a hobby for 3 years (although I was qualified as a radio and TV engineer 40 years ago). So I've probably not seen enough of them yet.

[@ScottGrammer]

Nice video! Subscribed.

[@billyclayton1154]

Too much heat can be your enemy but, flux can be your best friend. I've found if you've got the shakes try a sandwich. It pains me to say that cause I'd rather be working, but working hangry is counter productive. Nice job.

[@oldavguywholovesRCA]

Thank you

[@hestheMaster]

Excellent tutorial repair and check.

[@oldavguywholovesRCA]

Thanks 👍

[@jesse1779]

How do you determine the value to use of the schematic doesn’t tell you

[@oldavguywholovesRCA]

Guessing mostly but I've played around with them before and 100 pf seems to be pretty common.

[@tubeDude48]

Also see: *Jim Burns,* he really tares them down. I keep plenty of 100pF CAPs around just for this problem. In frame, in frame! It starts arching.

[@oldavguywholovesRCA]

I'm sorry, not a very skilled cinematographer. I get into what I'm doing and forget about the camera. I need a small monitor hooked up to the camera that I can keep an eye on my framing.

[@tubeDude48]

@@oldavguywholovesRCA - It happens.

[@nazeerabdulrahuman9526]

Thank you for the valuable information It’s really useful to me

[@ronvinsant9863]

Why not use a surface mount cap as opposed to a leaded mica cap?

[@oldavguywholovesRCA]

Thats actually what should have been done, not a lot of room in there.

[@mranalogman3525]

If you consider that route, make sure you use one that can withstand the voltages encountered in tube equipment.

[@tomm7096]

How did you figure out the capacitor spec?

[@oldavguywholovesRCA]

The schematic had the values listed for once.

[@UpcomingJedi]

If your schematic doesnt show the values, once you remove the caps, just measure the coils to select tht proper replacement capacitor for the resonant frequency

[@UpcomingJedi]

I would never get a prying tool. My luck i would snap the 70 year old plastic of the transformer. Might as well just throw the radio into the wall.

[@oldavguywholovesRCA]

I've done that too a few times

[@totallysmooth1203]

Half the video is done completely out of the frame of the camera. No thumbs up on this one.

[@UpcomingJedi]

Be thankful he didnt film his thumb for the second half.