Saturday, December 08, 2007

Las Vegas UHF Mysteries

Been working in the Las Vegas, NV region this week and have found a few UHF frequencies that I've had trouble pinning down who the users are. Thought I would throw them out to the blog page and see if I could get some input...

407.3250 MHz, D051 - Security operations. Might be related to activity on 407.5250 MHz (see below). This frequency is allocated as a federal Itinerant local use repeater.

407.5250 MHz, D023 - Definitely sounds like a military security net. I've thought it might be Nellis AFB, but this analog repeater does not seem to be patched to the NNSA UHF system the rest of Nellis seems to be using. The frequency is allocated to various DoD services.

409.0250 MHz - This frequency started showing an EDACS control channel. It is showing that it is LCN 3 of Site 7, so I am guessing it is part of the NTTR (Nevada Test & Training Range) trunked system, although this frequency has not been listed as part of this system in the past. Changes in the UHF channels may be showing up in the local trunked systems as well.

409.3000 MHz, P-25 - This seems to be a stand alone P-25 repeater, but everything on this has been encrypted so far. This frequency is allocated to various agencies, including the Department of Energy as well as DoD.

415.5750, D754 - Another security operation, but definitly NOT military. Very "civilian" radio procedure. The frequency is primarily allocated to the Department of Agriculture, but also has some NOAA and US Postal Service allocations.

Thursday, December 06, 2007

Another VHF Trunking Mystery?

A few months ago some reports from the east coast indicated that there was an EDACS trunking system operating in the VHF federal band somewhere nearby. It was determined that it was a two-site analog EDACS system belonging to the NASA facility at Wallops Island, VA.

Now a report has appeared in one of the Radio Reference forums that a similar VHF EDACS system is being heard in the Houston, TX area, but the poster believes that this system is being heard via skip or ducting and is not local.

The frequencies reported heard are 163.5625 MHz, 164.5000 MHz and 165.0875 MHz. These frequencies are often associated with military facilities and the US Army Corps of Engineers, so my first guess would be a military base in Texas or Louisiana.

Anyone else hearing these frequencies active?

406.6625 / 415.6625 MHz Update

A while back I asked folks about hearing activity on 406.6625 or 415.6625 MHz. I received several responses and it now appears that this frequency pair is being used nationwide by the Federal Reserve Branch Banks for security operations. What is interesting is that in some cases these systems are analog and some are P-25 digital.

Here are confirmed locations that these frequency pairs are being used:

Boston, MA
Dallas, TX
Houston, TX
Kansas City, MO
Memphis, TN
Miami, FL
San Francisco, CA

The Dallas Federal Reserve Bank is also reported to be using a repeater on 410.4875 MHz(input should be 419.4875 MHz). Can anyone else hear that pair in use?