900 MSF (CXB) and LTR...

CTAMontrose · Post by **CTAMontrose** » Wed Aug 03, 2005 6:45 am

ok so ive decided to play with LTR but want to retain the PL capability as well, this is going to be a one ch 900 hammie system... i have looked at the trident controllers but wanted to solicit input as to other models i may have overlooked.

its going to be attached to a 900 MSF CXB station and having conventional operation is a must as well.

thanks

bernie · Post by **bernie** » Sat Aug 06, 2005 3:18 pm

My two bits worth;

The Trident Raider can support both LTR as well as Multi coded squelch operation.

The controller sends a short data burst every 10 seconds "Idle Message".
This can annoy conventional users, is required for LTR operation.
The "Attack Time" of the Trident on PL decode is noticably slower than a stand alone station.
Zetron also makes a controller.

The MSF should be programmed as a base station, not a repeater, CSQ.

CTAMontrose · Post by **CTAMontrose** » Sat Aug 06, 2005 4:26 pm

is the LTR blip PL/DPL encoded?

in other words, if the station was transmitting PL or DPL in conventional mode, would it also encode the data burst for LTR?

bernie · Post by **bernie** » Sat Aug 06, 2005 6:50 pm

My two bits worth:
The LTR (Logic Trunked Radio) has it's own digital protocol.

The" MCS Overlay" allows operation of specific tone PL, as well as DPL (DCSS) codes.
(MCS= Multi coded Squelch, aka Community repeater)
Each specific code requires a specific system ID, similar to LTR users.
Should the channel be in use, the other systems on this channel are directed to a vacant channel. 300 baud (low speed sub audible signalling)
Conventional users must monitor, or have busy lock out.
This would be ideal if you intend to grow the system to 3 or more channels.
Otherwise, if this is only for single channel, a Zetron MCS panel would be the best, and least expensive way for a single channel multi user system.
Unless the existing subscriber units are LTR only.

CTAMontrose · Post by **CTAMontrose** » Sun Aug 07, 2005 2:27 pm

yeah i may just make it an LTR only solution, i kinda wanted to have PL/DPL for users that only had conventional, but that may be more of a PITA than its worth..

hell i guess i could get just an LTR controller, then if i wanted to go back to conventional, i could just pull it and reproggie the station as a repeater using the internal controller.

any ideas on where i could obtain a used LTR controller that would be compatable with the MSF?

thanks bernie!

MSS-Dave · Post by **MSS-Dave** » Tue Aug 09, 2005 6:41 pm

grem467 wrote:yeah i may just make it an LTR only solution, i kinda wanted to have PL/DPL for users that only had conventional, but that may be more of a PITA than its worth..

hell i guess i could get just an LTR controller, then if i wanted to go back to conventional, i could just pull it and reproggie the station as a repeater using the internal controller.

any ideas on where i could obtain a used LTR controller that would be compatable with the MSF?

thanks bernie!

Hi Grem...

Late to the thread but I've done lots of Tridents to CLB stations for UHF, no CXB as of yet. Sure it can be done though. The Trident acts as a total controller, meaning you disable ALL of the functions of PL/DPL and timers in the station, the controller does that. You then program the controller for your selected ID(s) you want on LTR and then you set up the ID(s) you want for conventional and set the PL/DPL code you want. It will work, however when the repeater is in use on conventional, the LTR radio cannot monitor and will do the busy beep if someone tries to access the repeater. When the LTR idle message burst goes out, it does NOT have any PL/DPL encoding on it, users with carrier squelch will hear a short carrier every 10 seconds or so, unless you program up coded squelch, then they hear nothing.

LTR is a cool protocol but it really is quite cumbersome as a single channel trunk site, especially if you are mixing conventional and trunk on 1 channel.

Dave

KB2ZTX · Post by **KB2ZTX** » Wed Aug 10, 2005 8:58 am

Well some more info for you. We run numerous sites with the trident controllers. I love them for ltr and conventional. I have one set up on a uhf ham freq, with both ltr and conventional and have never had a problem. The cool thing with the "trunking" system is if the ham channel is busy they controller will trunk the ltr to the other repeater. We havn't had many issues with them. In my own thoughts i have wanted to assemble a 900 Mhz 2 channel ltr site as equipment becomes available. Let me know how yours goes

JAS

CTAMontrose · Post by **CTAMontrose** » Wed Aug 10, 2005 9:05 am

the only legality i am running into talking about a multi site TRS for the ham band is the IDing...

with one repeater, the controller would ID the repeater, and the users would never hop to a different freq, therefore IDing wouldnt be an issue.

i would love a multichannel system if i could ever figure out how to not make it "grey area" for identification.

MSS-Dave · Post by **MSS-Dave** » Wed Aug 10, 2005 9:13 am

grem467 wrote:the only legality i am running into talking about a multi site TRS for the ham band is the IDing...

with one repeater, the controller would ID the repeater, and the users would never hop to a different freq, therefore IDing wouldnt be an issue.

i would love a multichannel system if i could ever figure out how to not make it "grey area" for identification.

This is NO problem for the Trident as you can make all of the channels ID independant of each other.

Somewhere, I may have a .pdf of the trident raider controller manual... you interested if I do?? It may answer a lot of your questions on configurations.

Dave

CTAMontrose · Post by **CTAMontrose** » Wed Aug 10, 2005 9:27 am

yeah i would love to see the book, if you find it let me know, i can have it sent to my Gmail...

how about the users? sure most of the time with LTR they would be on their home repeater, but if they jump to LCN2 for example, and they ID, then go back to LCN1 and continue their convo does that count as an ever 10 minute ID thing to keep part 97 happy?

MSS-Dave · Post by **MSS-Dave** » Thu Aug 11, 2005 8:26 am

how about the users? sure most of the time with LTR they would be on their home repeater, but if they jump to LCN2 for example, and they ID, then go back to LCN1 and continue their convo does that count as an ever 10 minute ID thing to keep part 97 happy?

Not sure I understand what you mean here... for the users to hear both conventional and trunk conversations, you would have to program system scan for the mobiles/portables. In trunk, the radio listens on the home channel programmed for that system. If that home channel is used for conventional, the radio sees activity on that channel as foreign to the system and will ignore (squelch) the audio and will not allow you to TX or will give you the bonk bonk of system busy. If you are system scanning, the radio has to scan to the assigned home channel of the trunk system, then listen for the idle message to see if it needs to unsquelch, if not it scans off to the next channel you have programmed. TG scan within a system is very fast, conventional scan is fast too but system scan is very slow between systems or between trunk system and conventional.
The part 97 thing would be every 10 minutes while in use, don't have to ID when not in use. LTR controllers in general I would think would ID every 15 minutes due to the part 90 regs. ALL of the active channels in a LTR system send idle messages, even when not in use so legally they would need to ID, either on frequency or on the lowest frequency in the system as long as all the channels fall under the same license.

Still looking for the .pdf, know where to get it if it's not on the laptop at home.

Dave

CTAMontrose · Post by **CTAMontrose** » Thu Aug 11, 2005 8:40 am

let me see if i can type this better.. lol

with a conventional system, the user would ID every 10 and at the end of the conversation. If the users were to switch to a different repeater, they would ID before moving to the other repeater.

In a trunking environment, they could end up on different repeaters several times during a conversation.... but still only being IDd every 10 and at the end.

in other words, on some frequencies they may not ID at all. I dont know if part 97s IDing rules are frequency dependant, or if they would take into account that they are iding properly 'on the system'

so legally they would need to ID, either on frequency or on the lowest frequency in the system as long as all the channels fall under the same license.

thats the thing i was wondering, if this rule also applies to pt97

as for the infrastructure, since the trident will ID all the active LCNs, that takes care of part 97 for it.

im sure around here there will be some repeater police that will be nit picking the heck out of this.. they REALLY get their undies in a wad over the astro machines... lol

kcbooboo · Post by **kcbooboo** » Thu Aug 11, 2005 9:23 am

The ID requirements for each emitter must be met.

Individual users would ID every 10 and at the end of their conversation.

If one or more repeaters rebroadcast the user's transmissions, then the repeaters must have their own IDs, also every 10 minutes, and usually at the next 10 minute interval of non-use.

A listener would hear the individual user's ID through the repeater, as well as any repeater, on any frequency that was used, give its own ID.

Bob M.

CTAMontrose · Post by **CTAMontrose** » Thu Aug 11, 2005 9:30 am

so as long as they ID as usual, it doesnt matter what frequency they have hopped to on the system.

that makes sense as anyone monitoring the talkgroup with an appropriate LTR scanner or radio would be able to verify they IDd properly

MSS-Dave · Post by **MSS-Dave** » Thu Aug 11, 2005 10:40 am

You got 2 different thing going here as far as the ID thing goes...

Part 97 and Part 90 have 2 different ID requirements. If this is going to be a ham thing with only 1 channel, there is no problem as the station ID and the repeater ID will be on the same channel. In a commercial environment, the repeater output and input frequency for mobiles are licenced to a user under 1 callsign (usually..). The callsign can be given automatically by CW on the repeater. The only ID the users need to give is a "assigned" unit number or name, here in Florida, "1 this is 2","yo bubba" or "yo querio Taco Bell" at lunch time suffice..

In the ham world, the repeater has to be ID'd by call AND the user has to give his call. Somewhere, I saw a discussion of the trunking on the ham bands topic and I think there was an opinion given by Riley Hollingsworth as to the ID of stations and operation of different protocols like LTR, /\/\oto and EDACS. I follow what you are saying, if you are monitoring with a trunk tracker ar a radio programmed for the system, you will follow the talkgroup in progress. The FCC is not interested in talkgroup info, they are only interested in the technical aspects of the radio transmitter on the assigned frequency so this would probably be the "gray area" if there is one regarding emission type or ID requirement.

Dave

CTAMontrose · Post by **CTAMontrose** » Thu Aug 11, 2005 10:51 am

i would love to read what riley said about the modes... as a one CH solution, you are right, the ID would occur on the same freq every time.. no big whoop. Honestly this is why i chose LTR over MOT trunking systems...

this arose if i wanted to add additional LCNs to the system..

kcbooboo · Post by **kcbooboo** » Thu Aug 11, 2005 11:07 am

Well, if every "used" frequency did its own ID every 10 minutes and at the conclusion of use, wouldn't this handle the situation you're proposing? The individual users would ID their own signals, and the repeater system would handle its own signals. If the signal hops around and causes several transmitters to go on-the-air, and they all identify according to the rules, I would think you're completely covered in every aspect, no matter who's listening to the input or the output(s).

If you follow the rules about identification, a user who kerchunks a repeater without carrying on any conversation is technically illegal as there was never an ID given out for that transmission. Of course, one could argue that if the user later, within 10 minutes, DID carry on a real QSO, and did give IDs as required, then the kerchunk wouldn't be a problem. But I can tell you as a repeater trustee, that never happens. People key them up all the time to see if their radios are working, or in some cases, to learn CW by listening to the ID or even just the courtesy beep. Of course, they only get a very limited vocabulary that way !

Bob M.

Big Towers · Post by **Big Towers** » Tue Sep 06, 2005 7:17 am

My two cents, and one who seldom follows the rules for iding.

It would be my guess that the requirement for an Amateur to ID every 10 minutes and at the end of the conversation is to identify the user of the frequency the user is talking on. The repeater IDs are for the trustee of the repeater, not the users of the repeater(s). So in the strictest interp of the reg, it would likely be a very "grey area" if a person talks for nine minutes on the input freq to repeater A, then goes away to repeater Bs input and talks there for nine minutes. While his 10 minute ID may be made "on time", it will be on a completely different frequency than the one he spent nine minutes on. The requirement to ID is in PArt 97 as a whole and is not specific to repeaters, or ASTRO, or HF, or packet, or AM. It is specific to the station transmitting on a specific frequency, regardless of mode.

Another example would be a guy who is talking on an HF freq at 14210 say. Then decides to move up to 14250 and talk there. The ID was required on 14210 before leaving to 14250. Insert any freqs you want in this scenario from DC to daylight, same requirement. I can be talking on our UHF Conventional Repeater on one site, then have the guy move to another one and talk there, same thing, ID required before leaving the first repeater to go to the second.

So unless the FCC has issued some sort of special dispensation for operating trunked systems on Amateur freqs, the rules of 97 are a wee bit different than 90. Personally I doubt if anybody gives a rats ..., but you never know!