What's the name of this part?

[Podbuilder]

As the title suggests..  just looking the name of this part.  A slide variable resistor??  It's from a 1960's radio to adjust the bias on the audio transformer driver.

[boater sam]

Skeletal linear preset potentiometer?

[PerdioPal]

Seconded.

[ppppenguin]

Skeleton preset potentiometer aka variable resistor. Nasty little things. If it's setting the output bias, depending on how it's wired, it's a good way to destroy the output transistors. The examples I've sketched may not be exactly as in your set but they are typical.

In the very bad example, even a slight intermittent contact will kill the output transistors. In the better example at least it can't go open circuit but a bad contact can still cause way too much bias. Best way is to have a fixed resistor doing most of the job and the pot just trimming the bias.

It would be useful to know the make and model. Ideally a circuit (schematic) diagram, but we may be able to find that if we know the type of set.

[boater sam]

Even used in Hackers, always been unreliable in my experience.

[DrStrangelove]

Found some of those in one of those bargain parcels I was so addicted to in my youth.

One at least was wirewound and ended up in the fuel sensor of my late & unlamented Vauxhall Chevette.

Must have saved at least £10 on a new part.

[Podbuilder]

Thanks.