Help identify a part please!

[PurpleStrat]

I bought a tube intercom to try a conversion to a guitar amp on and found it had no power transformer. The positive side of the plug goes to this part here. I have no idea what it is. It has Briton written on it and a + and - sign. What is this?

[Enzo]

That is a selenium rectifier. If it ever burns out on you, it will release a stink you will remember the rest of your days. I describe it as a sort of burning rotten cabbage smell.

It might last another 40 years, but I'd replace it with a plain old silicon diode - a 1N4007 should be enough.

That orange cap in the view looks like it is bulging out its vent.

Those transformerless amplifier circuits are extremely dangerous. If you want to use this for guitar amp, I HIGHLY recommend you add an isolation transformer to the mains input. That is just a 120v in to 120v out transformer that maintains the same power input to the amp, but it is no longer directly connected to the mains.

[PurpleStrat]

Thanks I would have never guessed! I have been thinking of ditching the idea of converting it but I'll check in to an isolation transformer.

[Bruce / Mission Amps]

Yikes... as my dear old dad use to say, "that's uglier then a bucket of smashed butt holes" but he didn't say butt holes...