ham radio "trunking"

[k2jlb]

I think the FCC should allow "trunking" in the ham bands. It really helped the public service radio problem...... Why can't we do it. It would eliminate some of the repeater coordination problems.


The only question is how would we do it?........Who would put up the repeaters? Equipment is only half the problem....Motorola obvious;ly make the equipment but it is expensive. I really think it would be worth it if we got enough people interested in it.

k2jlb@yahoo.com

[n8yx]

I think the FCC should allow "trunking" in the ham bands. It really helped the public service radio problem.....

Then only "problem" trunking really addresses is one of spectrum overcrowding..and that we aren't, in the majority of locales...

[k2jlb]

This is understood.

The way the trunking systems in South Carolina work is the users transmit on a control channel and a computer tells the repeaters and other radios on their talk group to switch to a specific freq........Standard stuff right?......Well like every other site uses the exact same freq's. They way they get away with it is by using DPL codes to keep the sites from interfering with each other. As far as the radios, say for example I am driving through town and you are talking to me (or to someone else) and I am in a spot where I can hear two sites at the same time.....You would think that I wouldn't be able to understand you because of the two repeater sites "doubling" with each other......Well the radios that we use have the ability to tell which site is giving off the strongest signal and they lock onto that signal and totaly disregard the other one.


The Sumter South Carolina system only uses 7 800Mhz freq's. Yet we have the local fire department, ems, police, sherrif department plus several other users all on that system at one time.

I think we can do it on the 900Mhz ham band.

The whole problem I have is that most repeaters that I have experienced aren't high enough to accomidate HT's. Well, I take that back....they are but not very well. I have to use crossband repeat from my car to access the repeaters from an ht (from inside a building). My local home repeater is on a towe 800 feet in the air and it works like a dream. But Here in N.C. around Fort Bragg, the repeaters suck. For mobile use they are great but HT use.....SUCKS!!

I suppose linking repeaters togeather would solve this problem. But trunking would allow better sharing of multiple freq's in a single area and would decrease having to wait for the repeater to come open.

[ai4ep]

the current system works fine just as it is.....thank you.

[KD6NIG]

Get 75% of the repeaters on paper in use, and we'll start having this discussion. But when I can look in the repeater guide, see 9 repeaters for Stockton, and only one gets any semblance of regular use, I don't think we're in such dire need of this :)

[wb5ydk]

But with various clubs and individual egos around, wouldn't there be a problem in deciding who controls the control channel?

[k2jlb]

I am afraid it doesn't. If it did there wouldn't be so many coordination problems.....paper repeaters......etc.

Some people put up repeaters on 50 foot towers, some people put up repeaters on 1,000 foot towers. Some run 5 watts, some run 200 watts. Some talk better than they can hear.....


The current system works yes but could be SO much better. Under the current system, repeaters should have a minimum and maximum power setting and a minimum and maximum height. This would allow for better coverage of multiple repeaters.


How would you like to be waiting for however long to get into a repeater that is 1,000 feet in the air and works great but is always busy. If there was a trunked repeater 1,000 feet in the air, many people could use the same tower at the same time. Or several repeaters at 100 feet...........

[KC9JUM]

This is something that should be allowed on the 33CM. Hams there love to convert commercial equipment anyway.

[k2jlb]

YESSSSSS!!!!! 900Mhz is the way to go. The equipment is available.....(if the money is......)

[k2jlb]

As far as the control channel goes, there should be only one dedicated control channel PERIOD. Clubs would apply for talk group id's and construction permits for the repeaters. This way no matter where you go, you would be able to access any system by just programming the talk group id in your radio.

Again, using DPL codes and applying a network freq stratagy, you won't have interference.

This is where coordinators come in.

On another thought......D-STAR should go trunked.

[N8EKT]

Trunking can be done at ANY frequency and is being done by more than just Motorola.

Trunking is the all your eggs in one basket approach that can and frequently DOES lead to problems.

First, the control channel is continuous duty at maximimum output which makes pa failures common power consumption tremendous and battery backup expensive.

Second, These systems usually involve multiple transmitters using one antenna via use of very expensive and very lossy combiners so that loss of one antenna takes them all out.

One lightning hit either on the recieve antenna or transmit would take multiple channels(repeaters) out in one hit.

[n5rfx]

I think the FCC should allow "trunking" in the ham bands.

What makes you think that the FCC does not allow trunking in the ham bands?

73,
Mark N5RFX

[k2jlb]

The whole reason that I even bring this up in the first place is that it is my opinion that people don't get into radio because of non reliability. People like cell phones because they can make a call in California and drive to New York and keep that same call. I know that you can do that on HF but if the band conditions change....poof....they are gone! That causes frustration. I feel the same way about VHF and UHF. I want to have solid clear communications local from an ht or atleast a vehicle. Without fighting for a clear repeater. I am not one to tie up a repeater for an hour talking about the ballgame or the weather (unless the weather is servere). I just want to know that I can make an emergency call without fail or make contact with my family and friends if need be.

I argue this based on the fact that manufactuers are making ht's smaller and smaller and with less output power. How can I make a call on a 300mw ht if I can't bring up the repeater? The only answer is to crossband repeat from a vehicle or another location. I could start another topic based on that but I won't. I'll just keep my Motorola HT's and have them programmed since I can't find a good 5 watt HT anymore.

[k2jlb]

You have a point. I don't see where the FCC doesn't allow it. But I just want to know if anyone else thought it was a good idea. I want to know if it would be worth it to try it. It would make no sense to set the system up if no one would use it.

[K7JEM]

It's not a good idea, serves no useful purpose in ham radio. Trunking is a limiting condition, not an expanding condition. Trunking can only make things worse, not better.

Joe

[WA0LYK]

The whole reason that I even bring this up in the first place is that it is my opinion that people don't get into radio because of non reliability. People like cell phones because they can make a call in California and drive to New York and keep that same call. I know that you can do that on HF but if the band conditions change....poof....they are gone! That causes frustration. I feel the same way about VHF and UHF. I want to have solid clear communications local from an ht or atleast a vehicle. Without fighting for a clear repeater. I am not one to tie up a repeater for an hour talking about the ballgame or the weather (unless the weather is servere). I just want to know that I can make an emergency call without fail or make contact with my family and friends if need be.

I argue this based on the fact that manufactuers are making ht's smaller and smaller and with less output power. How can I make a call on a 300mw ht if I can't bring up the repeater? The only answer is to crossband repeat from a vehicle or another location. I could start another topic based on that but I won't. I'll just keep my Motorola HT's and have them programmed since I can't find a good 5 watt HT anymore.

You're talking about a multitude of issues here, not just trunking.

Telephone companies, highway/street designers, call centers, etc. have used the queuing theories behind "trunking" for more than a hundred years. The basic purpose is to maximize the use of a LIMITED RESOURCE. The term limited is the key here. Fundamentally, the use of trunking will guarantee that there will be waiting times and/or blocking during periods of high use because you are discussing a limited resource. This shows up most when there is a need for maximum communications, i.e. a disaster. Basically, trunking is not a panacea for making sure you can make that emergency call. Because its main purpose is to maximize return on investment, trunking is used to invest in the smallest number of repeaters necessary.

Trunking will NOT GUARANTEE you that you will be able to access a repeater with your handheld either, even if you can reach the controller machine. If there are repeaters you can't use today because of a power limit in your HT, you'll still have the same problem after implementing trunking.

You have a very good trunking controller in your head. All you have to do is try different repeaters to find a clear one you can reach with your limited power. If you can't find one today using manual control, trunking won't help you at all.

Jim
WA0LYK

[k8jd]

There is not enough ham FM activity on all the VHF and UHF bands to justify one 10 channel trunked system on 900 mHz in a mid sized metro area. Besides who would pay for it and maintain it. :(

[WA9SVD]

Another white (or even pink?) elephant idea, of a solution in search od f a problem?:rolleyes:

How is it that you can't set up such a system yourself, or are all the repeater pairs in your area used, and you want a personal, private system and can't even get a primary channel assignment?

[NN4RH]

The whole reason that I even bring this up in the first place is that it is my opinion that people don't get into radio because of non reliability. . . . I just want to know that I can make an emergency call without fail or make contact with my family and friends if need be.

The thing is, though, when there's a disaster and the communications are needed most, it's the trunked systems that always go down first. Something goes wrong at that control point and the entire system becomes useless.

[K0RGR]

I don't think we'd want to go with trunking, per se, but I do think we could and probably should adapt some of the concepts for amateur use.

Instead of using trunking to share frequencies, how about smart radios and repeaters to automatically find and select a repeater for a QSO?

DSTAR already has much of this functionality - what I'm thinking though would be a system that would allow a mobile travelling cross-country to automatically find a repeater and make random contacts on it. If you add in the current DSTAR ability to create a route between two known stations on different DSTAR systems, you'd have a really power system!

[W5HTW]

The whole reason that I even bring this up in the first place is that it is my opinion that people don't get into radio because of non reliability. People like cell phones because they can make a call in California and drive to New York and keep that same call. I know that you can do that on HF but if the band conditions change....poof....they are gone! That causes frustration. I feel the same way about VHF and UHF. I want to have solid clear communications local from an ht or atleast a vehicle. Without fighting for a clear repeater. I am not one to tie up a repeater for an hour talking about the ballgame or the weather (unless the weather is servere). I just want to know that I can make an emergency call without fail or make contact with my family and friends if need be.

I argue this based on the fact that manufactuers are making ht's smaller and smaller and with less output power. How can I make a call on a 300mw ht if I can't bring up the repeater? The only answer is to crossband repeat from a vehicle or another location. I could start another topic based on that but I won't. I'll just keep my Motorola HT's and have them programmed since I can't find a good 5 watt HT anymore.

I'm not sure the object of ham radio is crystal clear, unbroken, border to border communications. We do that with landline telephones. The object of ham radio is as a hobby, not simply reliable communications, but challenge. And not just technical challenge but operating challenge. It would seem to me (and this is certainly how I feel) if every time I picked up the micrphone I had instant contact with where-ever I chose, with no complications and no challenge, I'd probably go to model railroading.

Trunking systems may could be of use in the whack... uh, EMCOM, areas on 900 mhz. I don't think it would please the majority of the ham community to have 2, or 70 cm, taken over by a commercial type system that took "ham radio" away from the users and made it land mobile.

If we redefine ham radio into public safety, we may lose ham radio entirely. And I'm not at all sure trunking on 900 mhz would accomplish what you seem to think it would, and that is wide area, noise free, interruption free, coverage. Probably, in order to use it on 900 mhz the FCC would have to allocate that band to ONLY trunking, allowing nothing else. The commercial users have that. We hams do not. I'm not sure we want it.

There is a push to turn amateur radio into commercial radio. This pressure, though, ignores the desires of what I think would be the majority of hams, in the interest of the few. We have already 'fixed' ham radio so much that it is barely recognizable. Too much fixing is going to fix it out of existence.

Careful what you seek. But more careful, please, about why you seek it.

73

[k2jlb]

OK, I'll lay this to rest. So the whole idea of trunking the 900Mhz ham band isn't such a good idea. I still believe there should be more regulations for repeaters. As I stated earlier, I believe that there should be a minimum and maximum antenna height and power setting. Possibly an inspection done to make sure that the reg's are being followed and the repeaters are actually on the air. I know it is almost impossible to get a 2 meter or 440 pair around here in NC or in SC. This would provide some better reliability.

I guess that goes toward the statement that was made about making ham radio more like public service and less like a hobby. Hmmmmm.

I like the idea that was posted just recently about making a radio that was capable of seeking repeaters as you travel. BUT to do that, the repeaters would have to transmit a control signal to the radio, just like in a trunking set up, to tell the radio the freq pair and tone. OR the radio would have to wait until the repeater was keyed by another user (or identified) to get that information.


I don't want ham radio to become public service. I enjoy ham radio....I just have different views on this issue. I don't expect everyone to agree with me.

[K7JEM]

I don't see what advantage trunking would offer to HR. We are a hobby, and want to communicate with the most people, not communicate in "talk groups".

There is nothing offered by trunking that is any way an advantage to us. It can only hurt, not help.

Joe

[K9STH]

There are trunking systems that do not require a "control channel". The "control" is done "on channel". Also, I have seen trunking systems using as little as 2 channels (this was done for a mid-sized school district south of Fort Worth, Texas).

However, for amateur radio use using a trunked radio approach basically turns the system into a series of "private" communication systems rather than the "open" system that is what amateur radio has been based upon for over a century.

Glen, K9STH

[KC9JIQ]

There is a push to turn amateur radio into commercial radio. This pressure, though, ignores the desires of what I think would be the majority of hams, in the interest of the few. We have already 'fixed' ham radio so much that it is barely recognizable. Too much fixing is going to fix it out of existence.

Agreed, don't fix what is not broken. But it is too late, the CODE was what made ham radio, ham radio! Now we got a breed of amateurs that NO CODE. I think we should allow IP over ham radio, and the such(like encryption with a unencrypted ID)

Again, Winlink on HF is a problem, and a good example of commercialization of ham radio.

Ham radio to me, is about experimentation, and the fewer restrictions the better. It would be cool to check email over ham radio(vhf+) D-star repeaters, APCO-25, IP over radio, IRLP, echolink, remote bases, QRO, QRP, bluetooth, wireless LAN, repeaters,etc.

Keep radio up in the "know", we need to be experimentating with new modes and with less FCC restrictions.

[N7RJD]

Main problem I see with this is having to afford a divorce after buying all new equipment. Besides, my truck doesn't have a trunk. :D:D

[ai4ep]

you know....he is right. A pick up truck HAS no trunk. Check for yourself.

[KS4VT]

Coming from someone who manages an 800 MHz public safety trunking system, trunking in AR will only empty your wallet, give you major headaches, and will not give you any real advantages.

http://www.pbcgov.com/fdo/ESS/800MHz.htm

As we all know 900 is lossy, and even more so than 800 MHz. Equipment like tower top amps and their installation is expensive to purchase and install and would be required so the talk-back from the lower power subscriber is equal to the output of the repeater transmitters.

Other drawbacks would be ID management and who assigns them and turns them on? Or is the system going to run wide open? If so then the control concept of the system goes out the window. Who will assign and manange the talk-group allocations? If there are too many assigned to a system, and not managed correctly with priorities, it can be brought down to its knees very quickly if its a low channel system.

I'll also add that programming trunking systems in the subscriber equipment is not for the non-technical or weak of heart. Not only do you have the control channels to program in there are items like; talk-group hex id's, user decimal id's, talk-group alias'; call lists, scan lists, system personalities and linking them to channel assignments, just to name some of the more common.

On the legal side of things, the TRS control channel constantly transmits, and at least in the Motorola smartnet/smartzone, is unable to transmit a CWID. That is done on another non-control channel of the TRS. That would be an issue under Part 97 but isn't an issue under Part 90.

Sec. 90.647 Station identification.

(a) Conventional systems of communication shall be identified in
accordance with existing regulations governing such matters.
(b) Trunked systems of communication, except as noted in paragraph
(c) of this section, shall be identified through the use of an automatic
device which transmits the call sign of the base station facility at 30
minute intervals. Such station identification shall be made on the
lowest frequency in the base station trunk group assigned the licensee.
Should this frequency be in use at the time station identification is
required, such identification may be made at the termination of the
communication in progress on this frequency. Identification may be made
by voice or International Morse Code. When the call sign is transmitted
in International Morse Code, it must be at a rate of between 15 to 20
words per minute and by means of tone modulation of the transmitter, the
tone frequency being between 800 and 1000 hertz.


Someone made a mention earlier of tranmitter reliability, and to set the record straight, the constant transmitting control channel is actually the most reliable channel in the system. In the 7 years the 28 channel system I manage has only had one (1) cc roll due to a transmitter failure. 99.9% of the time it only rolls to one of the other 3 channels due to ducting where an illegal carrier is recognized by the system and it takes it out of the sequence for a few minutes.

What I think would enhance AR repeater systems, especially at 900 MHz would be the utilization of simulcast and voting technolgies. GPS timed signals coming at you from different directions and voted talk-back allows for a higher quality transmissions and can be deployed in either a conventional or trunking configurations. Our users saw an immediate increase of communication relaibility just from the amout of RF that we were transmitting out and the multiple site voted talk-back.

In closing, the trunking allows me to put 12,000 users on-line, but the simulcast and voting gives them seamless communications aross a 2500 square mile county. This is both indoors and outdoors which is what they care about the most.

[k2jlb]

Morse code is dead....Why do people keep bringing that up? I do have the code qualification but I refuse to use it.

The whole my truck doesn't have a trunk thing????? WTH does that mean?:mad:

Trunking doesn't belong in ham radio.....I GOT IT. END OF DISCUSSION.:mad:

I appreciate all of the useful information that came out of this. I wish the ones that contributed nothing but wasted space to this discussion would go bother someone else.

[K9STH]

JLB:

Back in the early 1970s, under the direction of A. Prose Walker (the FCC "amateur radio man") there were implemented all sorts of regulations concerning the technical aspects of amateur radio repeaters. At that time separate licenses were required for repeaters (those call signs started with a WR prefix) and the gyrations that one had to "go through" to get a repeater license were excessive. These included HAAT calculations, effective radiated power, and so forth. Now you have to remember that Walker's purpose in life was making amateur radio operators "more professional" than any commercial operator could ever "hope to be".

A. Prose Walker had been employed by the Collins Radio Company before going to work at the FCC. Therefore, he had a lot of friends at the "new" Collins Radio Corporate headquarters here in Richardson, Texas. He was invited on two separate occasions to talk at the Richardson Wireless Klub (K5RWK) regular meetings when he was in the Dallas area. On the second occasion he was actually in my radio shack for a "meeting after the meeting" with several of his "old friends" and the executive committee of the RWK. He was definitely criticized for his "amateur radio operators being more professional" attitude by a number of his old friends. However, he stood firm on this position.

Since the "head" of the amateur radio section of the FCC was in my shack for over 3 hours you can be sure that EVERYTHING in my shack was "perfect" in terms of FCC regulations. Now this was almost 2 decades before I was nominated for appointment as one of the FCC commissioners under George H. W. Bush (I made it until the last round but was eliminated in favor of the "usual" Washington attorneys).

The overly restrictive regulations concerning amateur radio repeaters almost "killed" new repeater installations. Fortunately, those regulations were rescinded after a few years and the number of repeaters increased dramatically.

Glen, K9STH