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Re: [Phys-L] weird elevator touch button switches



On 6/10/2013 6:40 PM, Bernard Cleyet wrote:
On 2013, Jun 10, , at 15:02, brian whatcott <betwys1@sbcglobal.net> wrote:

These may be a form of neon regulator which strikes at a voltage somewhat higher than 70 and given sufficient current to maintain ionization, holds that regulated voltage until the anode voltage is spiked lower than the maintaining voltage. These could easily provide a self-illuminated flip flop arrangement. The regulated voltage was controlled by the gas mixture used for the fill. It is vital to provide them with a limiting resistor, without which they are likely to self-destruct.

Brian Whatcott Altus OK

Nope, One works as advertised, i.e. apply 100 V. goes on when one touches the envelope top. The 73V may refer to the EMF regulation. My meter reads about 75V tho. Further testing: won't fire up to 170V (the max my PS [100V.] + abunch of 9 V. batts. in series will supply.) A 0.3 k ohm in series w/ the anode and a 0.1 micro Fd. parallel w/ the supply. The tubes (several suppliers) are about $44.

bc didn't wait. One day may check his OA2 or OB3s. or VR 75/105s etc.


Now the question is, is it the K-40 radioactive finger that initiates the discharge?
Not so much radioactive, as (relatively) conductive, so that the high-resistance path between anode and cathode is bridged externally by the finger, allowing the neon regulator to strike.
What else would it be?

Brian Whatcott Altus OK