VHF Analog trunking?

[kb0rpj]

are there any systems or radios out there that will do ANALOG VHF trunking? is it even possible? if not what bands is analog trunking allowed on.

 

[Thunderknight]

I think EDACS came in VHF, was used by the military.

I'm not sure I've ever seen one, but maybe LTR?

 

[svfd17]

Wirelessly posted (Mozilla/5.0 (Linux; U; Android 4.0.4; en-us; C5170 Build/IML77) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30)

The Motorola cp200 xls does ltr on VHF.

 

[rescue161]

There were also Motorola Type II analog systems in VHF.

 

[KB1VLA]

There is / was a VHF EDACS trunk in New Hampshire (Goffstown), but it is in the process of being shut down. I can also hear a VHF LTR MultiNet system from where I am.

 

[ecps92]

Tons, LTR, Motorola and now many are moving to TRBO and other DMR's

http://www.radioreference.com/apps/db/?action=regexp&regexp=vhf
The above are just the ones in the RR DB with the Word VHF

are there any systems or radios out there that will do ANALOG VHF trunking? is it even possible? if not what bands is analog trunking allowed on.

 

[mikewazowski]

The only band I haven't seen analog trunking on is Low Band VHF.

 

[Drachen_Fire]

IIRC, The Motorola CDM1550LS+ VHF was available for a limited time and could do LTR and Passport on VHF.

 

[phillmobile]

and dont forget mpt1327 the worlds most used trunking protocol, i own a 3 site system and would not dream of down grading to digital especially tdma with all its multipath issues.

 

[rapidcharger]

What I'd like to know is are there any v.h.f. public safety analog trunking systems still around in the United States. And by public safety I mean edacs, Motorola smart zone/net etc. not some ltr trunking used by businesses.

 

[domes]

and dont forget mpt1327 the worlds most used trunking protocol, i own a 3 site system and would not dream of down grading to digital especially tdma with all its multipath issues.

I know what you mean about digital downgrade. We have several UHF narrowband analog LTR trunk systems we downgraded to a Kenwood Nexedge Multisite and we lost all the advantages & benefits that are inherent to analog FM modulation. We no longer hear multipath crackle or any static at all. No fade, no carrier hiss or frying, no Doppler effect, no alternator whine, no engine acceleration and virtually no background noise. It is very difficult to hear vehicle movement from either end of a conversation like the old FM system. You only hear voice come out of the speaker. Its eerie.

And if you like MPT 1327 you'll love Nexedge Multisite which is based on MPT-1327 protocol, but much simpler to implement. The control logic data is integrated with the voice data and it is standard IP protocol. There are no separate logic and audio circuits to balance & maintain.

 

[902]

The only band I haven't seen analog trunking on is Low Band VHF.

There's no reason why it could not work if a low band mobile radio, like a Kenwood, was flashed with an LTR personality and the repeaters had LTR controllers. It would actually be pretty nifty.

Unfortunately, it doesn't require constant technology refreshes and the big boys wouldn't be able to make it a recurring source of revenue.

Come to think of it, a Motorola 6809 controller or a GETC drawer could be wired into those repeaters too for Smartnet or EDACS.

 

[rapidcharger]

are there any systems or radios out there that will do ANALOG VHF trunking? is it even possible? if not what bands is analog trunking allowed on.

I think it was just more to do with timing,
The old analog trunking systems of yore would have had a harder time getting all the additional frequencies those use in VHF rather than UHF or the relatively uncharted territory of 800 MHz. And 900 MHz for that matter.

When digital came along and narrow banding, and coupled with the fact that VHF was beginning to look like a ghost town, it once again became more viable once DTRSs came around. Just a guess. In absence of any replies that mention any,

 

[902]

I think it was just more to do with timing,
The old analog trunking systems of yore would have had a harder time getting all the additional frequencies those use in VHF rather than UHF or the relatively uncharted territory of 800 MHz. And 900 MHz for that matter.

When digital came along and narrow banding, and coupled with the fact that VHF was beginning to look like a ghost town, it once again became more viable once DTRSs came around. Just a guess. In absence of any replies that mention any,

That depends on where you are in the U.S. I've had to find frequencies for large VHF trunked systems after the equipment was sold and delivered to save the salesman's... behind. Folks, NEVER buy equipment before you know there are resources available to support it! To make matters worse, there were combiner limitations, the sites already had other equipment at them, so transmitters couldn't be within a certain kHz value of the existing receivers or transmitters, AND it was north of Line A (Canada). That meant that all of the omnidirectional sites the engineers specified had to be re-engineered to very low ERP and directive antenna patterns that pointed back into the jurisdiction to minimize signal incursion into Canada. There were still numerous HIA letters thrown across the border, with many leading down the path of three HIAs and an on-air test. It took two years between the FCC and Industry Canada to get this done - and it felt like building the pyramids every bit along the way.

The only VHF "pick of the litter" places I've seen have been where manufacturers lobbied to put in large 800 MHz systems - Like Florida. There, VHF makes the jurisdiction the "odd man out" and there is only patched interoperability potential.

Here's an interesting item - recently the FCC issued a Report and Order dealing with legacy trunked systems in VHF and UHF. If the trunked system has not been narrowbanded (on the license and in actual practice), it lost its FB8/MO8 protection and can be ignored. So, slowly, these things will all need to be narrowbanded if they have not already done so. For certain manufacturers, that means going to P25 or other digital technology. That's essentially a forklift upgrade of everything, including subscriber units most of the time.

Narrowbanding hasn't really created that glut of channels the pundits and industry bright lights had anticipated. The reason for that is that the channels are 7.5 kHz apart and have to nominally fit 11.25 kHz worth of signaling into them. The ONLY technology that fits entirely within the 7.5 kHz channelspace is NXDN. Everything else requires a certain amount of geographic separation from its neighbors - or the written consent to share frequencies and accept interference - in order to use. In areas where those extra frequencies were really needed, there still is nothing because there is usually a dominant user co-channel or immediately adjacent to the channel being considered. In my opinion, the only thing narrowbanding did was create an artificial crisis that killed off a number of working systems, mandating the licensees buy new equipment to replace them if the systems could not be reprogrammed. Manufacturers lobbied the FCC to disallow reducing the deviation and installing tighter IF filtering in receivers. We're seeing the backlash now, in reduced deployment of smaller systems. What should have happened was a channelization to 6.25 kHz to line up with the NTIA's plan, just like UHF. Then there should have been standard pairing with mobile frequencies that would only allow FX1 operations, but NEVER allow an FB or FB2/FB8 on them, with frequencies set aside for simplex use. Then "right size" the ERPs for the jurisdictions. No countywide coverage with countywide interference protection and 300 W ERP for a 2 square mile town. But none of that ever happened. Fail.

Public safety isn't assigned anything on 900. They can, however, be subscribers on privately owned SMRs.

 

[talkpair]

I can't tell for sure, but it looks like the State of South Dakota might be using analog voice.