GM Mark,
The easiest way to think of this is Diodes = Detectors; with high-powered RF
around, that becomes a Bad Idea. A possible alternative MAY be high-value
resistors to ground across the front end of the preamps. A representative
value would be 10 MΩ or greater, and I would match the resistances to ±1%.
However, Tim's warning still applies in that this mod may damage the
performance of the array. I only mention it because I've used it with kite
and balloon antennas to drain off static discharge, and it may prove useful
here.
73 de Lee KX4TT
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Tim Duffy
Hello Mark:
Installing diodes can cause severe problems with nearby broadcast stations.
During the summer months and lightning months I remove my preamps from the
antenna elements to protect them.
I am now just getting them installed tomorrow morning to prepare for the
Fall Stew contest on Saturday.
Be careful making modifications that may hurt your array performance
73
Tim K3LR
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Mark
Robinson
I have the DX Engineering 8 circle receiving array sized for 80/160m .
It has been a fantastic performer but I have suffered damage to the active
antenna amplifiers on two separate occasions due to nearby lightning
strikes.
I am looking at a way to protect these amplifiers. I was wondering if I can
add a pair or dual series pair (4 diodes in total) of back to back diodes -
say 1N3600, across the input to ground terminals on each amplifier. Will
this affect the performance of the array in any way ?
73 Mark N1UK
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