VHF Passport?

Jay911 · #1 (**permalink**) 02-02-2009, 10:00 PM

Hi all,

The wiki article on LTR implies that Passport systems are only available in UHF. I have just set up a very wide-area VHF system and have been told by a scanner listener in that area that the system is Passport. I'm several thousand miles away and unable to check it out for myself (at least, until I go on a planned vacation in that area in September).

Are LTR Passport systems popping up in VHF format now? Can anyone provide me some info on this?

Thanks

kf8yk · #2 (**permalink**) 02-03-2009, 12:55 AM

Quote:

Originally Posted by Jay911

Are LTR Passport systems popping up in VHF format now? Can anyone provide me some info on this?

Thanks

Passport trunking in VHF is available, here's an older product page that lists VHF trunking as an option to the Passport NTS controller:

http://tech.tridentms.com:8181/ProductNTS1.htm

Here's another resource that details some of the Passport trunking protocol specifics.

http://www.aeroflex.com/ats/products...7/passport.pdf

slicerwizard · #3 (**permalink**) 02-03-2009, 10:39 PM

Quote:

Originally Posted by Jay911

The wiki article on LTR implies that Passport systems are only available in UHF.

I don't think it implies that. "Most" != "All"

Quote:

Originally Posted by kf8yk

Here's another resource that details some of the Passport trunking protocol specifics.

http://www.aeroflex.com/ats/products...7/passport.pdf

(in case it isn't clear, this next bit isn't directed at either of the above posters)

Are there any references to "Passport" in that document? Actually, yes, there is one typo. The rest of the document references "PassPort". Any chance that RR (and its wiki) could get on board?

And what about "LTR Passport"? Is that in there anywhere? No? So why is it in the wiki?

C'mon RR folks, this isn't rocket surgery...

Starcom21 · #4 (**permalink**) 02-04-2009, 07:34 PM

Quote:

Are there any references to "Passport" in that document? Actually, yes, there is one typo. The rest of the document references "PassPort". Any chance that RR (and its wiki) could get on board?

And what about "LTR Passport"? Is that in there anywhere? No? So why is it in the wiki?

C'mon RR folks, this isn't rocket surgery...

RR? Info about LTR passport is in the RR wiki. If there is not enough info, it's only because someone has yet to donate their time to get it in there.

I assume you may be replying about the other article that you quoted, but then you start saying RR is missing the boat.

pro92b · #5 (**permalink**) 02-04-2009, 08:35 PM

The wiki calls the system Passport but Trident Micro Systems calls its system PassPort, which is a copyrighted trademark. It's a small difference but why not get it right?

There is no such thing as 'LTR Passport'. There are combined LTR and PassPort systems that share some or all of the voice channels. Dedicated separate LTR and PassPort home channels are required for the combined systems. The wiki says PassPort systems have at least three channels but a system near me has only two channels.

Jay911 · #6 (**permalink**) 02-04-2009, 08:59 PM

I'm as much a stickler for getting things right as anyone else, but are you guys really giving people grief over one letter's case?

All I wanted to know was if a wide-area VHF PassPort system was possible (and for what it's worth, in the RRDB, PassPort is listed as a subtype of LTR, so at least in the RRDB, there is such a thing as LTR PassPort), since the wiki seemed to imply there wasn't, and I wanted to make sure the stuff I was putting in the DB was correct.

slicerwizard · #7 (**permalink**) 02-06-2009, 02:45 AM

Quote:

Originally Posted by Jay911

there is such a thing as LTR PassPort

When this is the response from a DB admin, I guess we'll be seeing "LTR Passport" here for a long time.

BTW Bill, thanks for the informed response (for all the good it'll do)

DaveNF2G · #8 (**permalink**) 02-06-2009, 09:34 AM

PassPort is a legitimate variant of LTR. It is more similar to MultiNet II in some ways than to "LTR-Regular."

When I update my website again, I will fix the lettering for the PassPort systems there.

datainmotion · #9 (**permalink**) 03-02-2009, 06:28 PM

There is a wide-area VHF Passport system in use up there for the PD / FD. It has multiple sites covering quite a wide area across Montrose and San Miguel Counties.

Scanner Frequencies: Mountain Village Regional Public Safety System Trunking System, Mountain Village, Colorado

ve3nsv · #10 (**permalink**) 03-14-2009, 11:12 PM

Quote:

Originally Posted by pro92b

The wiki calls the system Passport but Trident Micro Systems calls its system PassPort, which is a copyrighted trademark. It's a small difference but why not get it right?

There is no such thing as 'LTR Passport'. There are combined LTR and PassPort systems that share some or all of the voice channels. Dedicated separate LTR and PassPort home channels are required for the combined systems. The wiki says PassPort systems have at least three channels but a system near me has only two channels.

You only need two channels for a wide area site with multiple sites and one channel for a single site with no other sites linked.

Single site = Home channel - Handles registrations and voice traffic

Linked sites or Wide Area -
Home channel - Handles registrations for radios homed on that site and voice traffic
Collect Channel - Handles roaming radio registrations and only handles voice traffic when all other channels are busy.

pachanga22 · #11 (**permalink**) 03-17-2009, 10:04 AM

The short answer is YES, you can construct a Passport system with VHF channels. It only differs from UHF in the channel numbering(DFAs).

There's a 3 site system with one NTS and 2 Extend sites hanging off of it in the Mobile Al. area, some kind of utility.

slicerwizard · #12 (**permalink**) 03-17-2009, 09:22 PM

Quote:

Originally Posted by ve3nsv

You only need two channels for a wide area site with multiple sites and one channel for a single site with no other sites linked.

Single site = Home channel - Handles registrations and voice traffic

Linked sites or Wide Area -
Home channel - Handles registrations for radios homed on that site and voice traffic
Collect Channel - Handles roaming radio registrations and only handles voice traffic when all other channels are busy.

Collect Channels aren't mandatory. You can have a single channel networked site, but I wouldn't recommend it unless call volumes are very low.

ve3nsv · #13 (**permalink**) 03-24-2009, 07:49 PM

Quote:

Originally Posted by slicerwizard

Collect Channels aren't mandatory. You can have a single channel networked site, but I wouldn't recommend it unless call volumes are very low.

How would the roaming work? Do you just configure the DFA's of the neighboring home channels in channel card configuration for the neighbor list?

slicerwizard · #14 (**permalink**) 03-24-2009, 09:48 PM

Quote:

Originally Posted by ve3nsv

How would the roaming work?

Poorly. Roamers can't register while the home channel is in use.

Quote:

Do you just configure the DFA's of the neighboring home channels in channel card configuration for the neighbor list?

Yep. Where a collect channel DFA entry would normally go, just substitue the home channel.