Mystery Valves.

[Joe]

I found a couple of valves in my loft earlier.

   

I think they came from a Dancette-type gramophone. The trouble is that the numbers have rubbed off.

There's nothing on the larger one and pins 1, 6 and 8 are not connected.

The smaller one has a Mullard logo and what looks like something-83. Only pins 3, 4 and 5 are connected so that looks like a diode to me.

I was wondering if there was any way of identifying them and if they're any use to anybody.

Cheers
-Joe

[ppppenguin]

UL84 and UY85 at a fairly good guess. The one with the bulkier electrode assembly is the UL84. you can try applying a voltage to the heater pins. Start low and work up to a sensible glow while measuring volt and amps. UY85 is 38V, 100mA, UL84 is 45V 100mA.

[Till Eulenspiegel]

The smaller valve will be an UY85 rectifier and the other an output pentode type UL84. They 0.1 amp heaters.

Till Eulenspiegel.

[tiv48]

if the record player had a mains transformer they will be ey and el instead of u
and may have come from somthing like this
rob t

[OldTickTock]

Here you go Joe some data for you.

       

Chris

[Joe]

Thanks everybody. All very interesting. No wonder I couldn't get the heaters to glow on 6.3V.