LED Lighting a Trimphone dial...

[Key2871]

 Correct, wire wound is more durable, and expensive, but it beats a carbon variable resistor, when it comes to attenuation of voltage. Turning up or down the power.

[19and41]

It's just a pot that uses resistance wire wrapped around a nonconductive horseshoe instead of a carbon rich track.  If you've had that corduroy feel when turning a pot it is likely wirewound.

[HarrySmith]

OK, now I get it, that "coduroy" feeling struck a spark in a synapse. AHA - I have used one.
Thanks for the clarification.

[twocvbloke]

They can also come under the name "Rheostat"...

[19and41]

The big ones do.  The smaller ones can handle a bit more power than the carbon track types. 

[twocvbloke]

I've just discovered side-emitting fibre-optic cable, have one LED shining into one end, place into the space where the tritium tube would be, somehow wire it in to be safely powered, and, that could work as a replacement......... 

I'd experiment with the stuff, but having bought a blown-up induction cooktop for £40, I'm a bit spent-up for the month... 

[19and41]

Looks like that would be just the thing.  I look forward to seeing how it will do for you.

[twocvbloke]

I just need to stop spending my money on unfixable junk (said induction cooktop has many blown up SMD components, so, no easy fix!!), otherwise I'll end up not eating for a month... 

Though it could help with weightloss.........

[Jim Stettler]

Side emitting fiber optic . That is an interesting concept. I pulled up an Amazon ad to see the stuff.
https://tinyurl.com/y46h3ons

[twocvbloke]

I've just had a thought about trying to stick one or two of the SMD LEDs I bought a while back on the ends of the tritium tube to see how that would work, only issue is, I can't recall where I put the trimmed-off LEDs I set aside for trying to wire up as another ring of LEDs... 

[19and41]

I went to the reviews and questions section of the Amazon page and found this answered question..

Is a cable with a fiber inside or just the fiber? It light all cable or just end to end?
Answer:
It's just the fiber. No surrounding cable. I expected it to glow like it does in the picture, but it doesn't. There is basically no "side" glow on the fiber and just transmits end-to-end.

Maybe your cooktop worked out to be the better investment after all. 

[twocvbloke]

There appear to be some fibre cables with an extension that sticks out of one side (hmm, do tubular shapes have sides??) which I presume makes the side-glow, but I only learned of the stuff today so haven't a clue really... 

Maybe your cooktop worked out to be the better investment after all. 

After having taken it to bits this evening, erm, no, not really, it seems to have well and truly gone bang...

(Off-topic pics)

[19and41]

That looks like lightning damage to me.  Were you in hearing range when it went off?

[twocvbloke]

It was like that when I bought it, it's water damage, apparently a pan boiled over, the amazing design of the cooktop let liquid in, and it got onto the main board, shorted mains to low-voltage sides, probably made one heck of a bang and then got sold to a mug on ebay (aka me!!)... 

So far, it's pretty much spare parts, namely the induction rings, the glass top, the metalwork and some of the wiring, so pretty much junk really...

[andy1702]

Going back to the trimphone (mainly because I know nothing about induction hobs), if the LEDs were kept in parallel then they would probably work off a couple of AA batteries. I'm thinking there might be space for said batteries on top of the terminals inside the case. Would that be the way to do it? I'm not great with electronics, so just putting the idea out there.