Saturday, November 23, 2013

Whats Happening on 345.000 MHz?

Both Chris Parris (ex-MT Fed File and new Spectrum Monitor fed columnist) and I have been receiving reports of strange digital signals on 345.000 MHz which a nationwide US Coat Guard A/G frequency assignment.

Mac KF4LMT in Georgia posted this on Thursday to the Milcom group: "when squelch opened, unusual signal heard weakly"

Tom M in Louisiana notes: "I hear the same data burst on 345.0 in Louisiana.  Actually the frequency moves around by a few khz.  I noted that on my Winradio display."
Also he posted on Nov 11, "Routinely hear a data signal on 345.0 sounds like chuck chuck chuck chuck."

Ric KD4JRX in eastern NC reported, "Heard USCG A/C 2003(1658z) E-City A/C a C-130J working USCG cutter Diligence on 345.000 NFM. Then after that A/C 2003 called E-City on 345.000 AM and said he would be RTB at this time. NBFM on 345.000 MHz interesting. "

So what do we have going on here? New voice encryption mode being used by the CG? As always your thoughts and report are always appreciated to the email address in the masthead.

Also see Chris Parris' comments and samples of what is being heard on his blog at