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Old March 16th 07, 03:56 PM posted to rec.radio.amateur.homebrew
Highland Ham Highland Ham is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 250
Default ? on neon light as static discharge device

Dave wrote:
I saw somewhere that you could use an NE-2 bulb between the antenna "hot"
lead and ground as a static discharge device for a receiver, but can't find
an NE-2 and don't know anything about neon bulbs. Anybody know if a
standard neon bulb rated at 125 VAC could be used in this manner? Or how I
could test it? I'm thinking about charging up a 50V electrolytic capacitor
and hitting the bulb with that, to see if it discharges the cap. I have a
..22uF 630V mylar cap between the antenna and the input to the tuner because
the 35V disc I had there got blown, so I know that static can be a problem
with my setup even though it is grounded at two points.
Would welcome any ideas anyone has on how to make this work...

============================================
To avoid building-up of static you can fit a say 47 Kilo Ohms
non-inductive resistor between what you call the 'hot' lead and earth.
This would not affect the received or transmitted signal.

I have fitted 2 non-inductive (carbon) 1 Watt resistors (47 KOhms) from
the incoming balanced feeder to earth at the Antenna Matching Unit.
This approach is obviously also OK with an incoming coax feeder.
At 100 W RF output the voltage would be 71 V at the transceiver. This
would dissipate a little over 0.1 Watt in the 47K resistor fitted at the
transceiver. Metal-oxyde resistors can for this purpose also be
considered as non-inductive.


Frank GM0CSZ / KN6WH