[SMCARA] METCOM 217 MHz interference

[Aaron Giles]

I have been listening around the METCOM 217.825 MHz data frequency since 
Tom mentioned their interference problem at the meeting on Thursday.  I 
have heard an occasional FM voice and FM/AFSK data transmitter about 
6.25 kHz below the METCOM freq.  Eventually I copied a CW ID from it, 
WQGF315.

Click on this link http://www.qsl.net/n8tvq/WQGF315.PNG to see the 
spectrum waterfall display.  I recorded this from a Uniden BC895XLT, 
with a tap I added to the 450 kHz IF.  I mix the IF down to 10.8 kHz and 
then feed it into the computer sound card.  Then I use the DL4YHF 
Spectrum Laboratory software to look at it.  Along the center of the 
waterfall you see the METCOM transmitters.  The CW ID is visible 
approximately 6.25 kHz down from the center freq.

WQGF315 is an Automated Maritime Communications System (AMTS) license 
held by Maritime Communications/Land Mobile, LLC.  Click this link for 
the license info: 
http://wireless2.fcc.gov/UlsApp/UlsSearch/license.jsp?licKey=2870470.  I 
found this AMTS band plan on the FCC site: 
http://wireless.fcc.gov/auctions/data/bandplans/AMTS_band_plan.pdf.

I found this web page for the company, http://www.mclmllc.com/.  The 
coverage map on the web site 
(http://www.mclmllc.com/PassPort/Coverage/BaltimoreCoverageDec2004.htm) 
shows a site in Mechanicsville.  I haven't went mobile to see if this is 
where the signal is really originating, but I think it's a good 
possibility.

Aaron Giles
N8TVQ