Here’s something that my dream reminded me of. “Cat’s eye ” tube.

When I was little, my dad used to have this huge vacuum tube radio. I think, actually this is it:

I think that’s what a Twonky would look like.

I am not sure of the model though, but there it is as I remember it. That was probably the device that introduced me to “radio buttons”. It’s tuning scale was a bit misleading – it was marked with names of different cities that you could supposedly get on the short-wave band. Prague, London, Paris, New York. Riiight.
It had one very interesting detail – a “cat’s eye” tuning tube.

“Cat’s eye” is a really amazing device. Basically it’s a tiny little CRT in a vacuum tube. It usually served as a tuning indicator. When you would turn a tuning knob, the pattern displayed on the tube would change. Here’s a more detailed article.

There were several names these tubes were known under. “Cat’s eye”, “magic eye”, “electronic eye” and just plain “tuning tube”. They were (and still are) a bit pricey, so they usually were included only on high end radios.

Here are just a few examples of such tubes from this amazing collection:

Besides being amazingly pretty, IMHO they are actually very user friendly. It’s just that in modern solid state device there is little need for actual “tuning”, but they would make wonderful sound level indicators. It’s a great visual feedback mechanism.

I am probably saying this just because I am into this whole glowing vacuum tube aesthetic though. Also these tubes make amazing blinkenlights.