What you're more interested in is not what voltage it fires at but how
fast. A visible spark from a simple static discharge is on the order
of 3000 volts or so... what you want is a gas-discharge tube that
fires in the nanoseconds -- faster than any semiconductor.

I recommend Polyphaser. I use them, I'm pleased with them, and
they've survived multiple near-strikes and one direct hit.

IT IS VERY IMPORTANT TO REMEMBER, though, that a gas-tube is only as
good as the SYSTEM set up around it. Polyphaser has papers on how to
do this sort of thing on their web page. Don't let the complexity of
their suggestions overwhelm you -- do stuff one-step-at-a-time as you
can:

Understand the concept of a ground window and use it
Ground rods that become ground rod systems as time, money and patience
allow
Checking over your system to make sure that nothing bypasses your
ground window


....etc.

I'm no shill for Polyphaser, nor do I have any financial interest,
other than the protection of my equipment. I'm just a satisfied
customer.




"Robert11" wrote:

Hello:



The folks at Antenna Supermarker have a gas tube lightning protector that
they claim fires at 1/7 (other text says 1/17)

the voltage of...



"Zap TrapperT Electronic Gas Tube Lightning Arrestors. Receive-only
design shunts damaging transients to ground at only 1/17th the voltage
buildup as compared to the commonly available 200 watt transmit-type
arrestors, providing maximum solid state receiver protection.



Protect your investment - combine an excellent shortwave receiving
antenna with the best receiver protection money can buy.



RCVR/T- Our maximum-sensitivity receive-only electronic Gas Tube
Lightning Surge voltage protector * Fires at only 1/7th of the voltage
buildup that is required to activate the lowest power (200 Watt)
transmitting-type lightning arrestors available, thus providing vastly
superior protection for solid state receivers * Uses two gas tubes * /T
model for twinlead-fed and longwire antennas * Input is two binding posts,
output is also two binding posts * No patch cable required. $22.95 "



I guess, but am not sure, that they are comparing the firing voltage to the
typical Alpha-Delta units.



I'm interest in getting some unit, frankly, probably more for supposed peace
of mind than anything else.



The 1/7 firing voltage sounds real good, as I do listening only, and am
always quite worried about voltage transients possibly being picked up and
ruining the front end of my receiver from nearby strikes if I'm not home to
disconnect things.



Anyone have any thoughts or opinions on the Alpha Delta units and these from
Antenna Supermarket ?



Which would you buy for a receive only setup ?



Thanks,

Bob






--
Eric F. Richards

"Nature abhors a vacuum tube." -- Myron Glass,
often attributed to J. R. Pierce, Bell Labs, c. 1940