Don't forget you'll still need power at the remote box for the receiver and
also for the relays themselves. Its easy enough to put dc or 60hz on
feedlines to power remote equipment, its easy to switch 4 relays with just
+/- half wave AC. an audio frequency pickoff would let you use something
like an old telephone modem for remote control... plenty fast enough for
antenna selection, rotors, etc.
But for my money I just use rcs8v remove boxes with good old wire connecting
them to the shack.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: jimlux [mailto:jimlux@earthlink.net]
> Sent: Friday, January 30, 2009 23:08
> To: lists@subich.com
> Cc: 'TowerTalk'
> Subject: [TowerTalk] fancy switches Re: Antenna Switch Needed
>
> Joe Subich, W4TV wrote:
> > I have to admit to being prejudiced but when top station builders like
> > those at Radio Arkla (OH8X) want reliability and flexibility, their
> > choice is the microHAM Station Master and microHAM single or dual
> > switches.
> >
> > See: www.radioarcala.com/nbspStation/RFSwitching/tabid/367/Default.aspx
> >
> > The current building blocks can be used for switching matrixes up
> > to 10 sources (towers) and eight destinations (transmitters). Each
> > source (tower) can be a switch for up to 10 antennas/feedlines.
> >
> > 73,
> >
> > ... Joe Subich, W4TV
>
> I've been thinking about using a small microcontroller with 802.11b on
> it (like from Rabbit Semi) for running remote switches. Do away with
> the control cables entirely. I wonder if anyone has any practical
> experience with the RF immunity of 802.11 receivers in strong HF fields
> (e.g. if you've got your little controller sitting near the feed or at
> the base of a vertical, etc. When you key up, will the 802.11 receiver
> block?)
>
> I was thinking of trying an experiment with just sticking a Linksys
> access point next to the antenna, and seeing if you can still "see" it
> on the network.
>
> The controllers are pretty inexpensive (about $100 ish in moderate
> quantities), and you could easily stick one inside/next to a standard
> switch box, and have the little 2.4 GHz whip stick out. Then, you
> wouldn't even need a box back at the shack (unless you didn't want to
> use a computer).. just a wireless network connection.
>
> I've tried using wireless ethernet to printer adapters, and they don't
> do well for this application These widgets like the dlink DP-G301 are
> about $60. I haven't tried that particular one, but I'm not very
> positive on the overall concept. They really want to see a printer at
> the other end, strobes, acks, etc. it's not like a PC parallel port,
> more of a wireless print server.
>
>
>
> I can see it costing $300-400 more at the remote switch end, but you'd
> save on the controller end and on the wires. The wires could be a
> significant chunk of change.
>
> Hmm. probably need to put a gain antenna on the 802.11 because you're
> probably talking hundreds of feet in the usual installation. OTOH,
> you'd could running the 802.11 at 2mbps.
>
> Once you get that two way link running, too, there's a lot of
> interesting things you could do.. remote antenna tuners, power meters,
> steppir controllers and so forth.
> _______________________________________________
>
>
>
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