[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Spark Gap Tubes



Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net> 

I don't know that the alpha source in a smoke detector would
a) have energetic enough particles... yes, they're 5 MeV alphas, but they
don't go very far before hitting an air molecule
b) have a high enough rate to make a difference.  1 uCi is 27,000
disintegrations/sec (as I recall) and they're distributed over 4pi, so most
won't be in the gap.

I've seen UV (short wavelength) and some strong gamma emitters used for this
(Co60?)

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Thursday, September 18, 2003 4:11 PM
Subject: RE: Spark Gap Tubes


 > Original poster: "Edward J. Metzler" <emetzler-at-accredo-dot-com>
 >
 > I am a newbie so please excuse my question if it is stupid or has been
 > answered before.
 >
 > I wonder if anyone has ever used a Alpha radioactive source (like those in
 > smoke detectors) to ionize the spark gap and see if it produces for
 > consistent sparks?
 >
 >
 > Edward J. Metzler
 > aCCredo - Proactive Risk Management
 > 13267 SW Bull Mountain Road, Tigard, OR  97224
 > (503) 624-2124)   (503) 624-5723 [fax]   (503) 805-7758 [cell]
 > email: emetzler-at-accredo-dot-com
 > http://www.accredo-dot-com
 >
 >
 > -----Original Message-----
 > From: Tesla list [mailto:tesla-at-pupman-dot-com]
 > Sent: Thursday, September 18, 2003 10:35 AM
 > To: tesla-at-pupman-dot-com
 > Subject: Re: Spark Gap Tubes
 >
 > Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net>
 >
 > Indeed, they are designed for high peak power and low average power.  The
 > idea is that they are in the waveguide heading to the receiver. The high
 > transmit power causes them to ionize, forming a short in the waveguide,
 > protecting the receiver. When placed the right distance from the hybrid T,
 > the short looks like an open to the transmit power.
 >
 > Often, these tubes have a bias voltage to keep them "simmering" so that
they
 > reliably fire.
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Thursday, September 18, 2003 2:43 AM
 > Subject: Spark Gap Tubes
 >
 >
 >   > Original poster: jwhitmor-at-muscanet-dot-com  >  > Anyone have experience
with
 > spark gap tubes  > (sometimes called TR tubes) from radar modulators?
 >   > I checked the archives and found a brief mention,  > but it does not
look
 > like anyone experimented with  > them. They were referred to as vacuum
gaps,
 > but  > this is incorrect, since they are gas filled and often  >
 > pressurized. They seem to have impressive  > specifications, but the
 > construction does not look  > like it could support the power levels
quoted.
 > My  > guess is the peak power is high, but the average  > power must be
 > rather modest. I have a 1B22 which  > is rated at 67AMPS for 0.75ms at
1000
 > PPS, or  > 2.25ms pulses at 330 PPS. Conduction starts at  > 2.7KV, about
in
 > MOT range. Big problem is, no  > adjustments to the gap are possible.
 >   >
 >   > Jimbo                        jwhitmor-at-muscanet-dot-com
 >   >
 >   >
 >
 >