MPT Trunked NET on 139.7125 MHz

Scanning radio frequencies in Yorkshire & Lincolnshire
Post Reply
User avatar
lincs_radio
Super Member
Super Member
Posts: 243
Joined: 02 Aug 2010, 00:40
Location: Lincolnshire, Eng (4 Miles S.E of EGYD)

MPT Trunked NET on 139.7125 MHz

Post by lincs_radio » 17 Jan 2017, 08:15

Hey Guys,
Its been YEARS since my last post on this forum. :o

I've recently been messing with an SDR using the RTL Dongle and stumbled across this MPT1327 Net on 139.7125 MHz.
Anyone has any info on this net? (Site ID: 0293)

The Ofcom WTR seems to be down at the moment so haven't been able to track down TX Site or further freqs.
Been monitoring it a few days now, but there doesn't seem to be any real users???
Only had a handful of Registrations over the course of a few days and no voice/data.

There are 5 Adjacent Sites... 028A, 028B, 02C9, 02CA, 02CB.
028B is at 139.7500, but again... nothing.

Thanks :thumbup:
LincsRX

milly
Super Member
Super Member
Posts: 327
Joined: 22 Jan 2009, 12:41

Re: MPT Trunked NET on 139.7125 MHz

Post by milly » 17 Jan 2017, 13:41

It's the remnants of the Utility company systems in spectrum amanged by JRC.

The nets were almost out of use (and that part of the spectrum handed over for the iBus system in the M25 area) - recently they seem to have been using them again around Lancashire and Yorkshire.

No doubt someone on here will be able to tell you which Utility company based on the SysIDs but I've long since forgotten them all.
"Search engine? How do I find that?"
"Sod it, let someone else do it"

radtech
Super Member
Super Member
Posts: 268
Joined: 09 May 2010, 20:22
Call Sign: Rich
Location: Notts.

Re: MPT Trunked NET on 139.7125 MHz

Post by radtech » 19 Jan 2017, 18:11

Hi.

As said above, utilities have used these bands for a while, however many shut down their radio networks in the early 2000's and moved everything to GSM. In the past five years however many have rebuilt their networks in response to government targets and concerns about the resilience of GSM in the event of a prolonged blackout situation for both voice and data comms.

You will be picking up Western Power Distribution's system which is easily identified as the control channel is broadcast in time shared bursts from different sites. All of their vehicles (from Fiestas to Flatbed trucks) have Simoco radios fitted but are really only there to be used incase of an outage or when out of GSM coverage, so the system is very quiet.

There is a new DMR Trunked system broadcasting around the 154 MHz area (6.25Khz offset channels) that you will probably get which at the moment is for data communications but is likely to replace the above system in the coming years.

Hope that helps!
Rich

User avatar
lincs_radio
Super Member
Super Member
Posts: 243
Joined: 02 Aug 2010, 00:40
Location: Lincolnshire, Eng (4 Miles S.E of EGYD)

Re: MPT Trunked NET on 139.7125 MHz

Post by lincs_radio » 20 Jan 2017, 00:02

Thanks Rich/Milly,
I've been away from the hobby for awhile, as I decided to pursue Aviation Photography & Virtual Radar (ADS-B/MLAT) to which I sold most of my radio equipment... since then, I've created a little family and simply don't have the time to get out as much as I would like so I'm slowly getting back into this side of the hobby. ALOT has changed in the 4-5 years i've been away though, obviously everyone knew digital would of course takeover from analogue but its been quicker then I predicted :-O most of the MPT1327 Nets, CBS Repeaters and other analogue stuff has since disappeared or gone digital... although I'm encouraged by the software that's now available to decode such formats.

Back to subject, Yes... The MPT1327 CC is in time-shared bursts, and yes, its VERY quite...

As for the New DMR Trunked System (Teir3), Yes... I noticed it prior to your reply, its at 154.6000 MHz, according to DSD+ (great software) the SysID is 'L1-7.2' but as you said, after monitoring it for a few days, nothing but data at present.

Rich, are you saying that the new DMR System will replace their GSM, or simply replace their old MPT1327 System as a backup incase of prolonged blackout?

Again, Thanks for your replies... please bare with me while I attempt to get back up to speed :-D
LincsRX

radtech
Super Member
Super Member
Posts: 268
Joined: 09 May 2010, 20:22
Call Sign: Rich
Location: Notts.

Re: MPT Trunked NET on 139.7125 MHz

Post by radtech » 20 Jan 2017, 19:19

lincs_radio wrote:
Rich, are you saying that the new DMR System will replace their GSM, or simply replace their old MPT1327 System as a backup incase of prolonged blackout?
WPD are moving allot of their systems monitoring from GSM (and UHF) to the DMR network, VHF co-linears on most assets now.

I'd imagine they will still be keeping their company GSM phones but it makes sense to migrate the MPT to VHF DMR. The current MPT system has very small cell sizes and combined with the time shared control channel isn't really be suitable for group calls, this is why it's currently setup like a phone service with handsfree VOX, one-to-one calls and PABX/PSTN to the office/switchboard.

The DMR trunked would give them a proper PTT radio system that groups of workers can actually use.
Rich

Post Reply

Who is online

Users browsing this forum: No registered users and 4 guests