• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

555 timer usage for purists

A photo:

555TimerChip.jpg
 
What output tube would use use to drive the relay for the soft start or HT turn-on delay?

The relay driver tube of choice in those old ultrasonic TV remotes of the 60's was a 12FV7. It's like a 12BH7 on steroids.

The remote itself was completely mechanical. A little hammer would strike a metal cylinder to generate a tone that could activate a motorized drive on the tuner, or volume control.

The receiver used a few tubes with a microphone to pick up these ultrasonic tones and turn on a motor via a relay.

A devious kid with a hand full of change, or a ring of car keys in a department store could drive all of the TV's crazy.
 
The remote itself was completely mechanical. A little hammer would strike a metal cylinder to generate a tone that could activate a motorized drive on the tuner, or volume control.

Flintstones, meet the Flintstones...

Don't laugh, those 1960's TV and console stereo remotes also had tuning forks that were hit by a button press - Magnavox, Sylvania, Zenith's "Space Command", early Philco's used a squeeze bulb with a rubber hose to the set.

And now look at us!
A bunch of old farts that can't get our azzs off the sofa.... just tap a button!
 
Ok, we can go back to using them when IR remotes are determined by the State of California to cause cancer, birth defects or other reproductive harm.

In one of my boxes of parts I have a relay with a 10 K ohm coil.

You have been selected as the first one to build a tube 555 and put it to work in a useful project! Unless someone who actually has one of those thyratrons in their stash speaks up. If George had some he’d be bragging and showing us pictures of nefarious uses fir them.

Who is up for building a tube Commodore 64? I’d pay good money to see that. I’ve heard of people building those out of 7400 logic, albeit with kHz clock rates. You *san* emulate all those with tubes, no harder than the 555. Just takes someone crazy and determined enough to do it.
 
Will this do?
It is in a nice wooden case with a number of other nice vintage parts.
It will need to be carefully extracted from the corroded clips and tested first.
It is not going to be easy with three top caps to come loose leaving me with a challenge.
 

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