[aprssig] Wireless Weather Station Frequency ?

[Dave Baxter]

Hmm...

Sniff the RF with a spectrum analyzer to be sure.  But, they'll probably
be using a spread spectrum modulation, so it may not be too easy to
find.  Even if they use a narrow band (FM or AM) modulation scheme,
it'll probably be a devils own job to hack the protocol to get at the
info you want.  Unless the maker is prepared to tell you of course, or
it uses really crude signalling much like model control links on 27MHz
used to years back, multi channel PPM and all that...

You may also find (as I have) that the RX will get nuked when ever you
spark up on 70cms, or with any reasonable power on 2m (3rd harmonic)
Most of those receivers are very non selective, and with easily blocked
front ends.  (Cheap!)

Other than the one time easy installation of wireless devices, I can see
no real advantage of them, that outweighs the EMC problems when used in
or near an active amateur station, or other similar wireless devices.
The remote unit still needs it's battery replacing from time to time, so
unless you're into rapidly deployed temporary setups, I'd go for wires
each time.

All good fun, I think...

Dave B.  G0WBX.


> -----Original Message-----
> From: aprssig-bounces at lists.tapr.org 
> [mailto:aprssig-bounces at lists.tapr.org] On Behalf Of Andrew Rich
> Sent: Friday, October 28, 2005 11:10 AM
> To: TAPR APRS Mailing List
> Subject: RE: [aprssig] Wireless Weather Station Frequency ?
> 
> We have some cheap ones without serial ports.
> 
> We want to build a black box that sits on the bench with a rx 
> module and serial port.
> 
> Or maybe we can hack the display unit.