[TowerTalk] Crossover Transfer Relay

[Joe Subich, W4TV]

The KK1L "three relay" configuration is a copy of the switching 
configuration used since the very beginning in the microHAM Double 
Six and Double Ten Switches.  See the basic information at: 
 www.microham-usa.com/Products/Antenna%20Switches/double%20ten%20switch.html

Unlike the KK1L switch which shows only 35 dB isolation at 30 MHz, 
the microHAM Double Six Switch provides >75 dB isolation at 30 MHz 
and >60 dB isolation at 50 MHz.  The Double Six Switch is normally 
compensated for SWR < 1.10:1 on all ports at 30 MHz but can be 
adjusted for < 1.3:1 on all ports at 50 MHz or optimized for SWR 
< 1.15:1 at 50 MHz on "port 6" at the expense of slightly higher 
SWR on other ports. 

73, 

   ... Joe Subich, W4TV 
       microHAM America 
       http://www.microHAM-USA.com 
       http://groups.yahoo.com/group/microHAM 
       support at microham.com 
  



> -----Original Message-----
> From: towertalk-bounces at contesting.com 
> [mailto:towertalk-bounces at contesting.com] On Behalf Of jimlux
> Sent: Saturday, March 14, 2009 6:30 PM
> To: W5KI at aol.com
> Cc: towertalk at contesting.com
> Subject: Re: [TowerTalk] Crossover Transfer Relay
> 
> 
> W5KI at aol.com wrote:
> > Jim,
> >  
> > Agree.  And thanks for your later comments about failure of one  of 
> > the ABSS.
> >  Something I didn't consider for Ken, since I use a  single 
> transfer switch 
> > here (the 300-11002-2 you mentioned [below],  good to 1 Ghz.)
> >  
> > Steve, W5KI
> > 
> 
> The recent reference to KK1L's switch is interesting. He uses 3 SPDT 
> relays per "antenna port", which makes it fail safe, at least 
> as far as 
> not connecting two radios together accidentally.
> 
> There's also an HP ap note, AN332, which I don't think is 
> online, which 
> is a good summary of all sorts of rf switching. I see it's not marked 
> with a copyright, so maybe I can put it online. I'll write to Agilent 
> and ask.
> 
> 
> 
> Jim, W6RMK
> 
> 
> BTW
> http://www.hpmemory.org/ressources/resrc_an_01.htm is a 
> useful resource 
> in general
> _______________________________________________
> 
> 
> 
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