Topband: 4 sq receive and high power

[Larry Molitor]

The HI-Z preamps do seem to be immune to any normal high power TX issues. I have had a HI-Z 4-sq up with the closest element only 65 feet away from the TX vertical with no problems running full legal limit. Currently I have a 2 element system in place only 30 feet away from my 40 meter 4-sq, also running full legal limit, and have seen no problems.

Back to back diodes are a very bad thing, they will cause all kinds of problems on RX.

73, Larry - W7IUV





>________________________________
> From: Ignacy Misztal <no9e at arrl.net>
>To: topband at contesting.com 
>Sent: Wednesday, January 4, 2012 5:47 PM
>Subject: Topband: 4 sq receive and high power
> 
>I was planning to buy a 4 sq receive system for the upcoming CQ160 contest.
>One question is about handling of high power when the 4sq cannot be put far
>away from the tx antenna. HI-Z claims that their system is immune to high
>power. DX Engineering claims the opposite and requires a sequencer. The
>sequencer adds complexity and cost.
>
>Did anyone experience a damaged amp in those systems? Would clamping the
>input of a vertical with 2 back to back diodes be acceptable?
>
>On a different note, the Hi-Z site states new legal problems and no sales.
>There 4 sq was about $770 with new amps. However, DX Enginnering has an
>"electrical only" option to HI-Z for $799 that appears equivalent to Hi-Z.
>However it is sold out. So neither is available. Not sure there is another
>viable option.
>
>Ignacy, NO9E
>_______________________________________________
>UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
>