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3 components?

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Hi all!
I found this old 300bytes external modem, and i took it to get some free parts. When i opened the box i found 3 components that i dont know what they do... heres a pic of them:

On the first one there reads someting like "~Pm 230 32"
On the second "480F-X205"
And on the third "501028" wich i think is the manufacturing date... it looks like some cind of transformer...

BUT if you know what they are plz tell me!



Active Member
The third one seems like isolation transformer. No idea about 1st and 2nd.


New Member
i think the first is a diode, an old type of, or it might be small soil..try mesure its resistance.....
about the second, i dont know what it is....i also bought an old ISDN controller and it has 2 things that loog just like it, i searched the net, but couldnt find anything about it.....
the third i'm sure it is a transformer, old modems uesd thme for insulation, most like a telephone uses them, new ones have other type of separation methods and protection....
ill search the net and c what i can find.....


New Member
Telephone Line Protection

I am sure the first component is a Varistor - it will seem open-circuit until it sees some high voltage across it (maybe 100v ?) when it becomes a near short.

It will be directly across the incoming telephone lines and provides lightning protection to the equipment. These things are now built into (UK) telephone master sockets so plug-in gear no longer requires them as the socket does the protection.

The second might be a low-pass filter but could be more line protection.

The third, I agree, is a line transformer.
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