My experience with the ICE filters is that one should be used on each rig to
be effective.
73, Keith NM5G
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Lux
Sent: Friday, October 06, 2006 2:24 PM
To: Al Williams; towertalk@contesting.com
Subject: Re: [TowerTalk] Building a "little pistol" contest station and
theC-31XR
At 09:22 AM 10/6/2006, Al Williams wrote:
>I had planned on using the C31XR with separate feedlines in a SO2R
>operation and then became concerned about how badly the close proximity
>of the elements would cause interference to the second rig and maybe
>even burn out the front end.
>
>I have all band Dunestar filters but was concerned about if the filter
>was accidentally switched out during the frenzied contest.
>
>EZNEC showed that the coupled signal could be quite strong on the
>adjacent elements?
And even with the filters, you're putting a pretty healthy out of band
signal into the victim receiver.
The other issue would be the spurious output from the transmitter that's on
one band that spreads into the adjacent bands. Say you're putting out 100W
on 15m, and the transmitter has (legal) spurious levels of -40 dB on the
adjacent band. That's +10dBm, in band, so the receiver filter won't filter
it out. If you had filters on both Tx AND Rx, it would probably help (-40
dB down spurs - 40dB for a filter is spurs down 80 dB at the tx antenna,
probably another 20dB down into the victim receiver.. that's starting to be
reasonable, although I hope you weren't planning on digging out S-0 signals
on the other reciever)
>k7puc
>
>
>----- Original Message -----
>snips
> >From: "Andrew Roos" <Andrew.Roos@poynting.co.za> My "Mark 1" station
> >will be the C-31XR at 70 foot, with wire antennas on 40 and 80m,
> >without SO2R capability.> To use the C-31XR with three separate
> >feedlines,
> >
> > (a) Do I simply need three baluns, or is there something else I
> > should order.
> > (b) Do I need to order the C-31 specifically for three-feed
> > operation, or do I just order a "standard" C-31?
> > (c) How easy/hard is it to convert between one and 3 feedlines once
> > it's on a tower? I imagine this may be hard, so I should probably
> > use three feedlines from the outset, even if I don't have the band
> > filters and second radio for SO2R.
> >
> > Andrew ZS6AAA (ex ZS1AN).
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > Andrew Roos
> > Poynting Antennas
> >
> > Telephone (011) 262-5155
> > Facsimile (011) 262-5156
> >
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > 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
_______________________________________________
_______________________________________________
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
|