Ed Gray's Magic Tube

[Turbo]

It's a small portion of another larger video in which the circuit is shown.

[tim123]

It's a small portion of another larger video in which the circuit is shown.

Hi Turbo,
  it would have been nice if you'd just posted a link to the full video - rather than expecting people to find it for themselves...

Having had my little moan, I have to say I found both these vids of yours pretty good:

- Marco's Dancing Magnets (I like this one a lot!) - http://www.youtube.com/watch?v=XghAn9olnsI
- Ion Wind - http://www.youtube.com/watch?v=aNwFKUm9xUs

How did your multipactor work out?

Regards, Tim

[tim123]

I've had a play with the tube I made... It works almost exactly as I thought it would under my test conditions...

- The 2 mesh 'collectors' experience capacitive coupling with the electrodes.
- The output is a bit less than with solid conductors
- Adding the outside earthed electrode does increase the voltage difference between the 2 collectors
- There's no noticable excess current coming from any ionisation, but then there shouldn't be...

I got the speed of sparking up to about 900Hz, and I think I can get it up to maybe 5KHz with some tuning & more power. Using about 40 watts ATM...

I've been reading about Farnsworth & Multipactors, from the links Wings posted. What a totally awesome bloke he was. I'm humbled by his genius. Wow.

[wings]

 
http://www.youtube.com/watch?v=FJFCnAA5oVQ


http://www.youtube.com/watch?v=1aY2vzmwfEs



original
https://www.youtube.com/watch?v=CS4zl3f1fFI&list=FLjGRhW_qGi4sZZZG4wXhIgw&feature=mh_lolz

[tim123]

Thanks Wings, good links.

I think I need to try the carbon resistor in the tube... Will see what I can find...

Here's a website with loads of cool home experiments - including making CR tubes...
http://www.teralab.co.uk/Glass_Blowing/CRT_A/CRT_A_Page1.htm

Edit: And another gray tube replication:
http://www.youtube.com/watch?v=m1aCmHL2xL8