Ron:
I built option #2 for the multi efforts at N4ZC. It worked pretty well.
You
only need one com port while the daisy chain requires two serial ports.
With
option 2 you can network and still have an open com port for rig control or
a
tnc etc.
It doesn't sound like an option but it would be even better if you could use
ethernet cards and coax, much easier to deal with in my opinion.
Ron D. Rossi wrote:
> Folks,
>
> Our field day group has been talking about networking our logging
computers.
>
> Rather than build special cables I thought of the following two ideas. The
> nice thing about these ideas is that any old printer extender or serial
> cable
> can be used.
>
> I am looking for comments from those of you that may have done this.
>
> Note: The ASCII diagrams won't display nicely unless you view this note
with
> a
> non-proportional font.
>
> 1) build an adapter for each computer to allow us to daisy chain the
> computers
> as required by the logging program. You would one cable to go between each
> computer. This is a 100% custom adapter.
>
> DB-9 #3 (computer) RXD ---| |---- RXD DB-9 #2 (goesouta to the next CPU)
> TXD ---|---|
> |
> |-------- TXD DB-9 #1 (goesinta from the prev
CPU)
>
> 2) build a central connection which does the daisy chaining in one place.
> This
> would allow us to separate computers by as much as 2X the cable length
used
> to
> connect to the box. Any position not in use would have a TXD/RXD shorting
> plog
> installed. This contraption can be made from a rewired 1 of 4 DB-9 switch
> box
> for a meager $15 new...connectors and metal enclosure.
>
> DB-9 #1 RXD------|
> TXD---| |
> | |
> DB-9 #2 RXD---| |
> TXD-| |
> | |
> DB-9 #3 RXD-| |
> TXD---| |
> | |
> DB-9 #4 RXD---| |
> TXD-| |
> | |
> DB-9 #5 RXD-| |
> TXD------|
>
> ---
> 73 de KK1L...ron (kk1l@arrl.net) <><
> QTH: St. Albans, Vermont
> My page: http://www.qsl.net/kk1l
>
> --
> CQ-Contest on WWW: http://www.contesting.com/_cq-contest/
> Administrative requests: cq-contest-REQUEST@contesting.com
--
73,
Richard Thorne - N5ZC (Ex. KA2DSY, N2BHP, WB5M)
Amarillo, TX
Web Page: http://www.tcac.net/~rthorne/index.html
--
CQ-Contest on WWW: http://www.contesting.com/_cq-contest/
Administrative requests: cq-contest-REQUEST@contesting.com
|