[UK-CONTEST] 2x6 Antenna Switch

[G3SJJ]

You only get what you pay for Jim. Looks to me as though you want a WX0B 
Sixpak without actually paying for it! It handles Standard Contest Power 
well and has about 80dB isolation between radios at that power rating, 
and is built on a PCB. I seem to remember reading an article on how he 
modifies standard relays to increase isolation. Just about the install 
the GU8D Sixpak here as a permanent system. Open up your wallet!

http://www.arraysolutions.com/Products/sixpak.htm

Chris G3SJJ


Jim Martin wrote:
> I am looking to build a six antenna to two radio switch box.  I cannot
> justify a commercial unit at £300+.  Having only two antennas at the home
> QTH it will only be used when out portable contesting (that is until we buy
> our Highland B&B and build a huge antenna farm!!)
> Two articles I have found so far are http://www.qsl.net/ei7ba/remote.htm
> from John's excellent site and
> http://www.qsl.net/k5lxp/projects/CoaxSwitch/CoaxSwitch.html which is very
> close to what I am after.  With this design I could complete the project for
> about £120, using 5amp relays from Maplin. (P/No. QC82D rated 240v X 5amp =
> 1200w, maximum output at the moment is 100w and hopefully these relays would
> cope with 400w in the future?)
> I have a slight concern using this in a multi-op environment. If an antenna
> is in use by station A it cannot be selected by station B which saves me
> sending 100w into the other rig. Unfortunatly this rig is then left without
> an antenna and is shorted to ground.  Disaster if the operator is not paying
> attention to antenna selection.  Are there any newer designs  which address
> this problem or have additional input from the band decoders?
> The current set up is 2 x MP-STUBS relay switched controlled by band
> decoder-auto BPF controlled by band decoder-antenna(soon to be 2x6 switch
> box, manual control)
> Having spent years keeping the coax and antennas from two stations as far
> apart as possible I am feeling a bit anxious at having both 100w outputs
> within a few inches of each other on a PCB!  Is there anything specific I
> need to do to ensure isolation of the two signals and a restful nights
> sleep?
> Are there better relay options?  I will need 20 in total as I need to build
> a new stub switching unit.
> As always your thoughts and advice would be appreciated.
> 73
> Jim,  MM0BQI
>
>
> _______________________________________________
> UK-Contest mailing list
> UK-Contest at contesting.com
> http://lists.contesting.com/mailman/listinfo/uk-contest
>
>