P25 and low band

[INDY72]

Low Band Repeaters.... There are still several in operation as back up for the MS Highway Safety Patrol (MHP). 45.3200 MHz out. Yes full repeaters. They used to be the go to for long range car to car and interdistrict ops. MHP ran on low band until just a very few years ago. Now they run on an 700/800 MHz Motorola ASTRO - 25 Phase II Statewide TRS. The Mississippi Wireless Integrated Network (MSWIN) As an person that has both monitored and used VHF Lo, VHF Hi, 800 MHz ASTRO (both analog and digital TG's), and pure P25 ASTRO-25 Phase I, I must say that the clarity of P25 is astounding! Both in the clear, and fully encrypted using ADP and AES-256.

Yes, the reach out on 45 MHz was very good, but there were a lot of things that turned lovely audio into an static garbled nightmare. The range was somewhat less on 155 MHz for non repeater comms, but the audio was vastly better on the wideband and narrowband (before the FCC "forced" everyone to go there). Then I was introduced to the world of Trunking.... A lot of folks naysay it... For me, I have had 99% great experiences both using, and monitoring. And sorry, but digital and lowband just can't mix at high power. If you were to lock down the power and only have short ranges, then it might be feasible, but for high power you are wiser to go VHF Hi, UHF, or 700/800/900 MHz. Just my halfpence cause I can't afford to give you two full pennies and still pay the tax. :lol:

 

[902]

And sorry, but digital and lowband just can't mix at high power.

Do you remember the meteor scatter systems that used to be on 44.20 and 45.90? Those things had 20 kW ERP. There were two licensees and three licenses. Only one is active for 44.20.

Here's the active site:
https://goo.gl/maps/f8VKHkyGi4R2


Pretty nifty configuration. Seems the other sites were either never built or already demolished in favor of crops, except for another in Tipton, MO..

 

[RFI-EMI-GUY]

I beleive the Missouri Highway Patrol is licensed for about 5 KW on some of their low band frequencies, with satellite receivers all around.

 

[Hooligan]

I beleive the Missouri Highway Patrol is licensed for about 5 KW on some of their low band frequencies, with satellite receivers all around.

Please verify that via the FCC database & let us know.

 

[Thunderknight]

Please verify that via the FCC database & let us know.

E.g. Location 2 on this license.
KAA202 (MISSOURI, STATE OF) FCC Callsign Details

 

[RFI-EMI-GUY]

Please verify that via the FCC database & let us know.

Here is yet another one.

Public Safety Pool, Conventional License - KAA203 - MISSOURI, STATE OF

 

[nd5y]

Here is yet another one.

There are about 9 of them. Each troop HQ has a 5 kW base and several 100 to 350 watt fill-in sites in outlying areas.

If you look at the limitations on the 42 MHz state police frequencies in the public safety pool frequency table you will see:
(3) Base stations operating on this frequency and rendering service to state police mobile units may be authorized to use a maximum output power in excess of the maximum indicated in §90.205 but not in excess of 7500 watts: Provided, That such operation is secondary to other stations.

None of this is news to anybody who knows anything at all about low band.

 

[902]

Here is yet another one.

Public Safety Pool, Conventional License - KAA203 - MISSOURI, STATE OF

I saw this up close and personal before "Kirkwood" became "Weldon Spring." It was a PECO power amplifier with a GE exciter. There was also a Daniels in there as a backup.

Their remote sites used to be bases linked by UHF "poor man's microwave" links.

Here's an invaluable writeup of MSHP radio history:
http://www.mshp.dps.mo.gov/MSHPWeb/PatrolDivisions/ICTD/documents/HistoryofCommD_004.pdf

Much, if not all, of the MSHP has migrated to MOSWIN, a VHF/700 MHz hybrid trunked radio system.

 

[902]

There are about 9 of them. Each troop HQ has a 5 kW base and several 100 to 350 watt fill-in sites in outlying areas.

If you look at the limitations on the 42 MHz state police frequencies in the public safety pool frequency table you will see:
(3) Base stations operating on this frequency and rendering service to state police mobile units may be authorized to use a maximum output power in excess of the maximum indicated in §90.205 but not in excess of 7500 watts: Provided, That such operation is secondary to other stations.

None of this is news to anybody who knows anything at all about low band.

They actually had a waiver of the rule.