Warm up some EL84 - 12ax7 tubes for decorative purposes only

[HeaD]

Hi all,

this one may sound silly to most people, sorry about that.

I got a bunch of old EL84 and 12ax7 tubes and I would like to make a design piece to put on my desk, with all those tubes lighted up.

I need just to warm up the filaments. Any advice? Is it possible using a 4.5V to 12V power supply?

Thank you! 

[kaycee]

Why not put a couple of orange LED's through or under  the bases and run off of a battery? I've seen it done on a couple of valve caster type designs where the filaments don't actually glow during use and its quite convincing. If you really heat the filaments you'll get quite a hot ornament!

[HeaD]

Hey kaycee, thank you for your reply.

Nice idea, but i want the "real feel". No matter if it gets too hot.

Thanks!

[merlinb]

Is it possible using a 4.5V to 12V power supply?

Yes, a 12V supply would do, provided it can deliver the current. The heaters are just like light bulbs really.

I too would recommend LEDs rather than wasting all those milliamps on a couple of small orange dots (actual heaters don't glow all the much really). Plus, it won't wear out the tubes, so your desk ornament becomes a cool tube storage area, rather than a tube old folks home

[psychedelicfish]

Hi all,

this one may sound silly to most people, sorry about that.

I got a bunch of old EL84 and 12ax7 tubes and I would like to make a design piece to put on my desk, with all those tubes lighted up.

I need just to warm up the filaments. Any advice? Is it possible using a 4.5V to 12V power supply?

Thank you! 

LEDs would be better, or rather than wasting perfectly good 12AX7s and EL84s you could sell/keep them and buy some cheap, (mostly) useless TV or radio valves. If they're old like you say, they might fetch a reasonable price.

[Invertiguy]

^What he said. While there are quite a few tv tubes that are quite useful for audio, there are a few types that are pretty much useless, like hv rectifiers, gated-beam discriminators (unless you like weird distortion! ), and remote-cutoff and dual-control pentodes (remote cutoff pentodes can be used in compressors, and dual-control pentodes can be made mOre linear by putting a positive bias voltage on g3, but in any stash there's likely to be more of these than you can use). But I digress. Save those 12ax7s and el84s fOr an amp!

[psychedelicfish]

gated-beam discriminators

I must say I hadn't heard of those, so I googled them. Valve Ringmod?

[HeaD]

Save those 12ax7s and el84s fOr an amp!

You know, those are some old used tubes... got them from some amps after replacements. I'm just trying to think up a new funny purpose.

How do I power them properly?

Thank you so much.

[merlinb]

How do I power them properly?

Connect the heaters to voltage.... You know how to wire up a lightbulb, right? Same thing.

[zombiwoof]

I have a bass player friend who acquired a bunch of off-the-wall, cheap, cool-looking vintage big bottle tubes of various shapes, and arrayed them in a row on a base, and lit them up like the OP is talking about.  He set the lit-up "tube display" on top of his amps at gigs, it got some attention for sure.  Many people asked him exactly what it did (which basically was "nothing" but look cool).  Not sure how he did it, though.  When he told me about it I was wondering about his sanity, but when I saw it in action (inaction?), I understood the appeal of it.

Al

[duck_arse]

I stuck an EL-small something into a chipboard base, covered the bottom with leopard print toy furr and the top with metallic gold glitter sticky plastic, marked the base with "for emergency use, only" and gave it to my mate when he came out of hosp after his heart valve replacement.

don't think he's used it yet, and it was crackly anyway.