Re: LF: Off topic

[Dick Rollema <dickrollema@casema.nl>]

Dear Brian,

Thanks for your reply. I also possess Reference Data for Radio
Engineers. I found the info you proviided on page 921.  This is
what I was looking for!

73, Dick, PA0SE

At 20:48 10-3-05, you wrote:

Hi Dick
 
Looking in my trusty "Reference Data for Radio Engineers" (won in a rally raffle at least 40 years ago !) the spark gap voltages chart indicates about 30 kV per inch for "needles" and between 55 and 80 kV for spheres spaced and inch apart (depending on the size of the spheres). Hope that helps.
 
Brian

Dick Rollema <dickrollema@casema.nl> wrote:

TYo All from PA0SE

I am presently writing an article for our VERON magazine Electron  on the early radio experiments by Marconi. In these experiments spark gaps played an important role. Because I would like to perform some simple calculations on the peak power radiated by a spark transmitter I am looking for data on the break down voltage of spark gaps, consisting of two spheres.

In literature, found on the Internet, 75kV/inch is quoted but it is not stated whether this is between points or spheres and that makes a lot of difference.

Temperature and air pressure also influence break down voltage but I will forget about that, reckoning with "normal" conditions  of,

say , 20 degrees centigrade and  1000 hectopascal or whatever as reckoned as standard  barometric pressure.

Your help will be very much appreciated.

73, Dick, PA0SE

JN22GD

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