Question about Digital Trunking Sites.

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cferguson4809

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Many years ago I had a scanner but I have been out of the game for quite some time, I have what I would consider an above average understanding of how digital trunking radio works, I do not know everything by any stretch of the imagination. The thrust of my question has to do with the scanners themselves. I am looking for a scanner that I can scan a whole system(57 tower sites), I would like for the scanner to move from one tower to another within the system without me having to do anything, much like a real radio. When I had my radio shack pro97 many years ago this was not possible or at the very least I couldn't figure it out.

Do any modern scanners support this kind of functionality?

If the answer to the above question is no, then is there any way to trick a gps supported scanner into having similar functionality?
 

n9mxq

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If you're talking about something like Illinois Starcom. Sure, a GPS enabled scanner will do it.. either of the x36's come with all the information to do it, just add a GPS.

But, if you're expecting to hear your home town from the other side of the state.. Well, it doesn't work that way. Each site will only allow talkgroups in their area, unless a subscriber from your town is on that site. So If I was in Springfield IL, I couldn't listen to Belvidere IL unless one of their units was in town, using the same site..
 

Ubbe

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You dont even need the GPS. You program all sites control channels, and voice channels if needed, and when one control channel comes within reach the scanner will stay there as long as the hold time is set to, up to 4 minutes, and if you receive any call during that time it will restart the timer.

If you loose the reception of that control channel, or if the timer runs out, the scanner will scan over to the other sites, just as quick as normal scan, until it finds one within reach. Normally you set hold time to something like 2 seconds to try and always lock on to a site that carry active traffic. But if you only would like to stay on one site as long as possible you could use the 4 minute setting.

/Ubbe
 

jonwienke

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Bad advice. Using GPS properly will prevent the scanner from wasting a LOT of time scanning stuff that isn't in range. If the scanner knows its actual location, it can intelligently scan only sites and frequencies that are within reception range. If you try to scan dozens of sites that are out of range, you will miss traffic on sites that are in range.
 

n9mxq

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I agree with Jon. Running all those sites with no GPS will make you miss the closest calls.. Kinda like having a 100 channel scanner with all channels unlocked.. 9 times out of 10, you're listening to something 2 counties away, when the house across the street catches fire.
 

ofd8001

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Yes the very best combination is a scanner connected to a GPS device that feeds location data to the scanner. That way only those sites and talkgroups that are within reception range are scanned.

I use a Uniden BCD 536 with the Uniden GPS device with excellent results.

Alternatively you can change your location via zip code entry. However it is tedious.

Just to put some numbers to attempting to scan 57 sites with each site averaging 8 frequencies per site means you are 456 frequencies for the whole system. If the scanner "scans" 80 channels per second, it will take about 6 seconds to do a complete cycle. With most transmissions lasting 3-4 seconds, you'll miss a whole lot of stuff.
 

Ubbe

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I have what I would consider an above average understanding of how digital trunking radio works,

I am looking for a scanner that I can scan a whole system(57 tower sites), I would like for the scanner to move from one tower to another within the system without me having to do anything, much like a real radio.

If the answer to the above question is no, then is there any way to trick a gps supported scanner into having similar functionality?
I understand your knowledge about trunked system and what you want the scanner to do without using GPS, like a real radio.

A Uniden scanner only scans control channels. 57 towers scans in less than a second if there is no signal.
It only dwells on control channels where there is a valid signal. This is how a real radio works.

If a tower is within reach you probably also would like to monitor it as it is in the neighbourhood and not in another state. A real radio will probably use zones and you can equal that to favorite lists or quick keys in the scanner. You program the towers geographicly either by location as towns/area or south/north/west/east or something to your liking, the way a programming guy would set up a real radio as the radio probably only handles 16 sites in each zone/location, but a x36 scanner can hold much more, probably all 57 sites in one scan list.

GPS assisted scanning will also work if you set up each tower with its GPS coordinates and configure your scanner correctly, but as you wanted the scanner to work as a real radio you do not need to go into that mess.

/Ubbe
 

jonwienke

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A Uniden scanner only scans control channels. 57 towers scans in less than a second if there is no signal.
Actually, the scanner checks all site frequencies for a control channel, because the control channel can change at any time with zero notice. So if there are 57 sites in the system and you scan them all, you are scanning more like 400 frequencies, which takes at least 5 seconds even if no control channels are found. So what you are recommending would waste at least 5 seconds per scan cycle of the system, and guarantees that you will miss a lot of traffic. It is a really terrible idea.

You program the towers geographicly either by location as towns/area or south/north/west/east or something to your liking, the way a programming guy would set up a real radio as the radio probably only handles 16 sites in each zone/location, but a x36 scanner can hold much more, probably all 57 sites in one scan list.
With the exception of simulcast sites, each site has its own entry in the system, and each entry includes the location of the site, and a service radius roughly corresponding to how far the site can be received.A Favorite List for theBCDx36HP scanners can hold multiple trunked systems, each with dozens of sites and thousands of talkgroups. Simulcast sites typically have only one entry for multiple sites, because they all broadcast on the exact same set of frequencies.

GPS assisted scanning will also work if you set up each tower with its GPS coordinates and configure your scanner correctly, but as you wanted the scanner to work as a real radio you do not need to go into that mess.
A "real" radio is also programmed only for 1-3 sites in the majority of cases, just the ones covering the user's work area, so your argument there makes no sense. Also, sites are already tagged with GPS info and service range in the RR and Uniden databases, so the only time you have to enter that stuff is when you are adding a new trunked system to the RR database. So that part of your argument makes no sense either.

Using GPS or some other means to know your current location, and intelligently selecting which towers to scan based on your location, is always the most efficient way to scan a system, no exceptions. Even for "real" radios, which often have built-in GPS anyway.
 

troymail

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Most any modern scanner will allow you to program and monitor all of the sites of a given system with no external attachments (like a GPS) and associated cables and power requirements required.

Uniden x36 scanners - without application a GPS or other special programming - will try to scan all of the sites and frequencies that you have programmed and enabled - looking for any active and decodable control channel. This will certainly slow down the switching from one site to another - even if stationary. On large systems, you can watch and see the scanner display one after another all of the sites being checked (even those not in range). Also by default, Uniden Sentinel programming software loads ALL site frequencies for the sites that you program for a given system.

GRE/Whistler scanners are designed to search the all programmed sites and frequencies for an active control channel frequency that meets and maintains quality thresholds. Once that frequency is found, the scanner will remain on that CC frequency (without user interaction) until the threshold values fall out of range at which time, it will check the programming again for a new and better frequency. Whistler's EZ Scan program software provides the option to import and load into your programming only those frequencies that have been documented as primary or alternate control channel. This can greatly reduce the number of frequencies that must be checked when looking for a good quality control channel.

You don't need a GPS - it's an option (and my description - "a toy") and it is still far from perfect for various reasons - but you don't need it. If anything, the GPS is needed only because Uniden didn't implement any smart logic to determine which site to scan. Like all of the programming, the GPS relies heavily on the data submitted by RR users which contains many errors that potentially affect what you hear (or don't). The GPS also has what I feel is a nasty side-effect in implementation in that it also controls which talkgroups get monitored at any given time. You can overcome it but not without alot of manual programming.
 

jonwienke

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Uniden x36 scanners - without application a GPS or other special programming - will try to scan all of the sites and frequencies that you have programmed and enabled - looking for any active and decodable control channel. This will certainly slow down the switching from one site to another - even if stationary. On large systems, you can watch and see the scanner display one after another all of the sites being checked (even those not in range). Also by default, Uniden Sentinel programming software loads ALL site frequencies for the sites that you program for a given system.
This is not accurate, at least if you program your Favorite List competently and have Location Control turned on in the Favorite List settings. When scanning from the main database or a favorite list with Location Control enabled, the scanner will only scan what it thinks are nearby sites, based on either GPS data (if one is connected), or a manually entered location. Location Control is always active when scanning the main database, or the scanner would try to scan every licensed frequency and system in the USA and Canada.

You don't need a GPS - it's an option (and my description - "a toy") and it is still far from perfect for various reasons - but you don't need it. If anything, the GPS is needed only because Uniden didn't implement any smart logic to determine which site to scan. Like all of the programming, the GPS relies heavily on the data submitted by RR users which contains many errors that potentially affect what you hear (or don't). The GPS also has what I feel is a nasty side-effect in implementation in that it also controls which talkgroups get monitored at any given time. You can overcome it but not without alot of manual programming.
This is also mostly inaccurate. If the scanner is only used as a base station, you do not need GPS. You can enter your location once, and the scanner will remember that location until you change it. But if you use the scanner in a vehicle, it is not a "toy", it is a critically important feature. Not having it makes programming much more complex--you must assign quick keys to everything, and remember those quick keys, and enter them into the scanner WHILE DRIVING to toggle things on and off as you travel. This is not only an enormous hassle, but a major safety issue comparable to texting while driving.

It is true that there are erroneous entries in the RR and Uniden databases, but most of the data is correct, and updates are available weekly. The data in the database has gotten better over the years, and there is no reason to believe it won't continue to do so. And submitting a correction to the RR database isn't that hard.

And Location Control of Departments (groups of talkgroups) is a feature, not a bug. I don't see the point of trying to monitor a talkgroup from a PD on the other side of the state that isn't carried on the local sites anyway. Statewide talkgroups are put in Departments with statewide service range (or should be).

Scanning with a GPS while traveling isn't perfect, but it beats all of the alternative approaches hands-down, and is getting better over time as errors in the RR/Uniden database are corrected.
 

troymail

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I'm not going to go back and forth with you on this (I'm not even reading past the obvious comments that I'm wrong). I fully expected you would disagree with my comments. My comments stood alone - yours always seem to want to contradict others vs. just leaving things alone. Make your point and allow others to make theirs. Stop at that point....

These forums are allow for users to ask for input and getting answers from all that offer. In each case, we all have our opinions.

I fully stand by my comments (just as I am sure you stand by yours).

As with any comments posted here by and user - be in one vendor or another, this radio vs. that one, Coke vs. Pepsi, Ford vs. Chevy, etc - it is up to the user to decide what information to use and how to use it. No one can or should decide for any user what they should or should not do - it's their choice.
 

jonwienke

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There is a difference between stating a differing opinion, and stating something factually incorrect.

Your statement that x36 scanners try to scan all sites in a system by default is factually wrong, and provably so. It is never true when scanning the main database, and is only true when scanning Favorite Lists that have Location Control disabled, which is something that you should never do if the Favorite List contains large statewide or multistate trunked systems.

The same is true of your statement that "GPS is only needed because Uniden didn't include any smart logic to determine which site to scan." Knowing your location in relation to the location of the broadcast sites IS the smartest and most logical way to determine which sites to scan. And GPS is by far the most accurate, smart, and logical way to keep your current location up to date when on the go. How would you propose to scan a multistate, multisite system intelligently without using any knowledge of site locations, or the scanner's current location?

It is also not a matter of opinion that using GPS to automatically toggle things on and off is far safer than frequently manually typing in quick keys while driving.

I agree that the much of the rest is a matter of opinion, which is why I used the "mostly inaccurate" caveat.
 

phask

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Disregarding all the other comments - what whiz-bang tower/antenna system do you have that could even begin to receive an entire state? Unless you are in RI?

To actually answer - the HP(HP1, HP2, 436, 536) series of Uniden would do that by just creating an FL of the entire state's systems. I'd think Whistler could also - but no firsthand experience. I've done it for Ohio - but can only receive 2-4 sites from home.

One other issue - you have sites that may use the same control channel freqs. in other parts of the state.

You need to better understand or explain what you are trying to accomplish.



Many years ago I had a scanner but I have been out of the game for quite some time, I have what I would consider an above average understanding of how digital trunking radio works, I do not know everything by any stretch of the imagination. The thrust of my question has to do with the scanners themselves. I am looking for a scanner that I can scan a whole system(57 tower sites), I would like for the scanner to move from one tower to another within the system without me having to do anything, much like a real radio. When I had my radio shack pro97 many years ago this was not possible or at the very least I couldn't figure it out.

Do any modern scanners support this kind of functionality?

If the answer to the above question is no, then is there any way to trick a gps supported scanner into having similar functionality?
 

ofd8001

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And the answer is "yes" but it comes at a cost of efficiency and likely missed missed comms. The scanner will spend more time trying to monitor sites too far to receive than it does on sites within range.

I still agree with Jon and disagree with Ubbe.
 

jonwienke

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I would like for the scanner to move from one tower to another within the system without me having to do anything
The only efficient way to achieve this when the scanner is mobile is to use GPS to keep the scanner informed of its current location, and to have good data regarding the location and service range of each site, and let the scanner automatically toggle sites on and off so that only nearby sites within reception range are scanned.

Every other option or scan strategy either requires the user to manually toggle sites on and off, or else bogs the scanner down with unnecessary scans of sites that are too far away to be received. This is true of both scanners and "real" radios.
 
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