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Old 08-12-2012, 11:14 AM
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GSM GSM is offline
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Originally Posted by citfta View Post
Hi tturner,

The link you provided is a much more likely scenario of what could have been done by Tesla. The only problem I see in his description is he has the voltage at the plate backwards. When the tube is fully turned on the voltage will be lowest at the plate and highest when the tube is turned off. This can still be used to control a motor or whatever as that method has been used for years. If you connect a high power source to one side of a motor and the other side of the motor to the plate of the tube, then you can control the motor with a signal on the grid of the tube providing the tube can carry the amount of current needed by the motor. Normally several tubes were connected in parallel to be able to carry enough current for a large motor. These were called thyratrons and most of them were made by GE. These are large industrial tubes and not the little tubes described in that silly circuits paper.

@GSM By your own admission you haven't even looked at the circuit we were discussing so your comments are totally without merit. And just for your information I am self taught in electronics and made my living working in the field for 50 years. Anyone can say "I know the secret, but I'm not going to share it because you need to discover it for yourself". All that proves is you know how to type.

Hi Citfa,

As I wrote, I did check your links and no appropriate circuitry was there.

I have always had the view that no one else is RESPONSIBLE for MY understanding, and conversely, that I am not responsible for anyone else's understanding, especially those who so self assuredly claim to *know* already.

So having had time to catch up on searches I should like to type more, hopefully without receiving personally aimed comment in return. I walk away from negativity, and those who are vexations to the spirit.

The secret within those early thermionic tubes were filaments of thoriated tungsten used by manufacturers competing for efficiency per directly heated filament Watt.

A thoriated tungsten cathode can be induced to release additional electrons if it is bombarded with a lesser electron stream attracted from an anode via a positive grid potential. If the tube is oscillated, then those additional cathode released electrons may be conducted away, again via the grid w.r.t. the anode.

Do please take a look at the TH Moray tube circuits,
also page 37 here >

There was a very recent video of someone doing this on YT, but I did not retain a link, and modern indirectly heated cathode tubes, even thoria coated types, would likely succumb to ion poisoning in a way which early thoriated wire heated types were not susceptible.

Cheers ............ Graham.
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