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@microham.com
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of jimlux
> Sent: Saturday, March 14, 2009 6:30 PM
> To: W5KI@aol.com
> Cc: towertalk@contesting.com
> Subject: Re: [TowerTalk] Crossover Transfer Relay
>
>
> W5KI@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
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|