K3 Front End Protection

[N0AZZ]

I have saw this posted before but not quite in this respect. I'm using 2
K3's with a Array Solutions SIXpack antenna controller SO2R, using 3
different antennas for HF a beam covering all bands 10-40m, vertical 10-160m
and a OCFD @ 55' 270' long 10-160m.

 

The OCFD is using the same tower as the beam only 10' from the feed point.
The vertical a Hy Gain AV-18HT with a top mounted kit for 160m is only about
125' from the tower very good radial field.

 

My "B" station K3 is a full Elecraft KPA500/KAT500/W2, the second "A"
station is a K3/P3-SVGA into an Alpha 87A legal limit + Palstar HF-Auto.

 

With these power levels I don't want to tempt fate but may very well like to
use both radios at the same time while monitoring another band on the other
radio and a quick call once in a while. I have looked at several front end
protectors but they to be all for just receiving antennas and preamps no
transmit ones Am I correct not to trust the built in protection in the K3
for this? It's a great radio but don't want to destroy it either by running
that much power in antennas so close.

 

If the K3 cannot handle this power could anyone guide me to a source that
sells something that meets my needs.

 

Thanks to all for your response.

 

73,

Fred/N0AZZ

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

[Stan Gibbs, KR7C]

Fred,

The best source of good information that I have found on operating multiple radios safely is the book by George Cutsogeorge, W2VJN: "Managing Interstation Interferrence".  It covers all the issues with running SO2R as well as other multi-transmitter configurations, and provides techniques to measure interference and mediate it.

The book is available from Array Solutions here: http://www.arraysolutions.com/Products/Books/W2VJN_Interference.htm

Antenna isolation is the name of the game and, particularly with QRO, requires a great deal of care and planning.  I run 100W in an SO2R configuration with 2 K3's on a small city lot.  My solution to the isolation problem has been the use of W3NQN bandpass filters and antenna geometries to minimize interaction.  Using W2VJN's analysis techniques and employing some of the possible solutions noted by him, I can operate safely and have confidence that I am not damaging my K3's receiver.

[Stan Gibbs, KR7C]

Stan Gibbs wrote

and mediate it.

Doh! That should be "mitigate it".

[N0AZZ]

Stan

Thanks I ordered the book looks like what I needed.

Thx & 73,
Fred/N0AZZ

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Stan Gibbs
Sent: Thursday, December 13, 2012 10:30 AM
To: [hidden email]
Subject: Re: [Elecraft] K3 Front End Protection

Fred,

The best source of good information that I have found on operating multiple
radios safely is the book by George Cutsogeorge, W2VJN: "Managing
Interstation Interferrence".  It covers all the issues with running SO2R as
well as other multi-transmitter configurations, and provides techniques to
measure interference and mediate it.

The book is available from Array Solutions here:
http://www.arraysolutions.com/Products/Books/W2VJN_Interference.htm

Antenna isolation is the name of the game and, particularly with QRO,
requires a great deal of care and planning.  I run 100W in an SO2R
configuration with 2 K3's on a small city lot.  My solution to the isolation
problem has been the use of W3NQN bandpass filters and antenna geometries to
minimize interaction.  Using W2VJN's analysis techniques and employing some
of the possible solutions noted by him, I can operate safely and have
confidence that I am not damaging my K3's receiver.




-----
73, Stan - KR7C
--
View this message in context:
http://elecraft.365791.n2.nabble.com/K3-Front-End-Protection-tp7567094p75671
00.html
Sent from the Elecraft mailing list archive at Nabble.com.
______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2012.0.2221 / Virus Database: 2634/5456 - Release Date: 12/13/12

______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html