On 2022-09-09, at 16:50, dbztuzujdhgtrjzthxh via groups.io <dbztuzujdhgtrjzthxh@...> wrote:
I thoroughly support replacing these filters on sight.
The first of mine that failed - it took weeks to get the smell out of the house.
Yes. And I still have tar marks on some furniture that was subjected to the jet of molten (vaporized?) tar coming out of the 3457A. Fortunately, that furniture was hard to set on fire.
The caps are only rated 250V which is ok on 110V, but no margin when used in the rest of the world.
That is a common misunderstanding of the problem.
These caps were rated for 250 V because they were designed and intended be used on 250 V mains. (250 V is the working voltage rating, not the voltage at which they start to fail ¡ª there is *plenty* of margin.)
It just turned out that the manufacturing process didn¡¯t actually serve to protect the innards from moisture ingress in the long run, which eventually causes the caps to degrade well below their rating.
The failure then indeed happens earlier (and is more catastrophic) in 230-V-land than in 110-V-land, but the failure is the same.
Depending on climate, moisture ingress is less heavy when the device is powered (warmer than the room) continuously. Then when it is decommissioned, put into storage, and ultimately sold on ebay, the problem hits.
This doc shows what is inside and how to rebuild if you can't find a suitable replacement
www.n4iqt.com/solartron/solartron-repair.pdf
These are great images to learn more about these line filters.
But if you need to replace them, getting a new line filter is a bit less of a waste of time.
If you try to repair the line filter: Definitely do *not* get a replacement cap that is again a clear blob of hard epoxy; these will fail the same way some 20, 30 years from now. Best get one with a plastic cup and some more ductile plastic filling covering the capacitor coil.
Gr¨¹?e, Carsten
