My longtime friend Mac McCormick (http://kf4lmt.blogspot.com/) has now confirmed which base one of my previously unidentified VHF high band military trunk radio system is coming from. Here is what Mac passed along last weekend:
"Some months ago when I took a trip to Columbia, Larry Van Horn sent me some frequencies to try on a VHF TRS that was either at Shaw or McEntire; the location was unknown at that time. During the Columbia trip, VHF conditions were such that it was difficult to determine proximity. On my trip today (March 31), however, I was able to determine that it was at Shaw and was able to determine the settings and monitor it some. "
Shaw AFB TRS 9600 Baud Motorola
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SETTINGS & FREQUENCIES
Base Freq: 162.0000, Step: 12.5 kHz, Offset: 380
163.4625 Control Channel (9600 baud)
165.0125 Digital Voice
165.1875 Digital Voice
165.2250 Digital Voice
165.4125 Digital Voice
166.0000 Digital Voice
166.2250 Digital Voice
TALKGROUPS
19 Fire?-FIRE DEPARTMENT wkg RADIO MAINTENANCE
20 Unknown-ref to personnel not in uniform going to "the 79th side"
21 Unknown
25 Police? - SHAW wkg DELTA #, references to "the sub-station" (these just "sounded" like law enforcement
28 Squadron talkgroup?-unid passing aircraft maintenance codes, reference to sending someone to "the 79th side" (probably related to similar traffic on TG 20)
34 Tower/Ground Control?-BARRIER MAINTENANCE wkg SHAW TOWER, -unid ref switching runways
42 POL?-unid ref "amount needed" for aircraft 907
Thanks Mac for taking the time to check my hunch. And I will have more on this and other new military trunk radio systems in my June 2007 MT Milcom column.