Thornton FD to 700MHz?

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SCPD

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MMIC said:
...except for the 700 MHz simulcast cell currently on the air in Adams county! :)

If it were simulcast it would have to be CELLS. So I'll bite, where are the (at least) 2 sites that are transmitting the same frequencies at the same time?
 

MMIC

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I watch 322 and Smokey side by side. The same radio will hit both sites, 700 on 322, 800 on 107, even though there are 700's available on 107.

The question is are all of the radios 700 MHz capable that are using the same talk group on site 107 as the radios that you know are 700 MHz capable? If even one of the radios that is on that talk group is not 700 MHz capable, the talk group call will be steered to the 800 MHz channels.

Is it possible to determine not only who gets to use a particular site, but who would get to use a particular set of frequencies on that site, such as the 700's, when a site is set up?

What band the radio uses for a call is determined by the radios that are involved in the call at the site. It appears that 700 MHz is the "primary" band on this system, so calls will actually default to 700 MHz at a site unless there is not enough 700 MHz capacity for the call at the site, or one of the radios involved in the call is not 700 MHz capable.

You are correct that radios and/or talk groups can be restricted from sites.
 

MMIC

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logitec said:
If it were simulcast it would have to be CELLS. So I'll bite, where are the (at least) 2 sites that are transmitting the same frequencies at the same time?

There are three, but that is as far as I will go......:)

But looking at this more logically - knowing that these sites are not on mountain tops, which some RDF work in the area confirms, other than extremely tall towers with cardoid pattern antennas (I have yet to see these in this band), it would be extremely difficult to provide the coverage that this system does, in the shape of the coverage that it is, without a simulcast system in place.
 

SCPD

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MMIC said:
There are three, but that is as far as I will go......:)

But looking at this more logically - knowing that these sites are not on mountain tops, which some RDF work in the area confirms, other than extremely tall towers with cardoid pattern antennas (I have yet to see these in this band), it would be extremely difficult to provide the coverage that this system does, in the shape of the coverage that it is, without a simulcast system in place.

Well, I'm hoping that your vague information is based on some inside knowledge and is not speculation.

I have no idea what the coverage of site(s) 322 is, since I have not spent any time mapping it. I wouldn't have the time to spend (or the interest) that it would take to figure out the non-omni shape of the coverage contour. I only know where I am, it's fairly weak.
 

RISC777

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Wednesday PM heard Thornton FD's dispatch (ID 29) twice between 21:45 to 22:15.
 

luke-1

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MMIC said:
The question is are all of the radios 700 MHz capable that are using the same talk group on site 107 as the radios that you know are 700 MHz capable? If even one of the radios that is on that talk group is not 700 MHz capable, the talk group call will be steered to the 800 MHz channels.

What about if there is a Pro-96 on the system that isn't 700 capable :lol:


What band the radio uses for a call is determined by the radios that are involved in the call at the site. It appears that 700 MHz is the "primary" band on this system, so calls will actually default to 700 MHz at a site unless there is not enough 700 MHz capacity for the call at the site, or one of the radios involved in the call is not 700 MHz capable.

Ok, That makes sense. Now at some point Adams County, for example, will have all 700Mhz. radios running. Would there have to be a patch set up for them to communicate with Arapahoe County, who has no 700 radios yet. Or would it default to 800 simply if one of the Arap. radios was on the Adams TG.

You are correct that radios and/or talk groups can be restricted from sites.

I realize this, but can you restrict Radios/TG's from using just certain Freqs. on a site?

Finally, since you are "inside the circuit", how big is this 700Mhz. drama actually going to get on this system?
 

MMIC

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Or would it default to 800 simply if one of the Arap. radios was on the Adams TG.

Exactly.

I realize this, but can you restrict Radios/TG's from using just certain Freqs. on a site?

No. The only partitioning of resources at a site will be between band plans.

how big is this 700Mhz. drama actually going to get on this system?

As time goes on 700 MHz activity will increase because of the lack of 800 MHz frequency pairs throughout the urban corridor.

And don't forget that M/A-COM is coming out with a new 700/800 portable very soon.
 
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luke-1

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No. The only partitioning of resources at a site will be between band plans.

That's what I was looking for

And don't forget that M/A-COM is coming out with a new 700/800 portable very soon.
Let's not go there quite yet


Will they be adding 700's to current sites that don't have any now, or are the current ones pretty well set?


I (we) appreciate the information. Keep us updated on what's going on with this (before it happens, if you can).
 

scanlist

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Ok guys it's not the end of the world. The state lights up a new 700 only site and people are ready to toss their 96's/2096's thinking that their neighborhood 800 site is going all 700 and rushing out to buy deaf uniden 700 capable scanners. Everything is still available on the 800 sites.

Obviously the N. Thornton 700 site allows all TG's on it for now. Good for site stress testing IMO. Chances are it will restrict some TG's when they get past the testing stages.
 

MMIC

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I have never heard of "site stress testing" before, and I have been in this industry for quite some time. Either it works or it doesn't. :)

The testing stages are long over for the simulcast cell. If it were not through with testing, it would not be live and taking the traffic that it is. Remember that part of being on DTRS is that all sites can carry any traffic off of any talk group and there are only very few exceptions. I would not anticipate that the simulcast cell would have talk groups restricted from it because of the coverage it provides in the northern part of the metro, and the general lack of capacity in the Denver area on DTRS. There will be certain radios that will "prefer" the simulcast cell, but they won't be restricted to it.

You're right that it's not the end of the world on 800 MHz, but I would more strongly consider a 700 MHz capable scanner if I lived north of I-70 in the Denver area.
 

scanlist

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I have never heard of "site stress testing" before, and I have been in this industry for quite some time.
Which industry is that? Exercising the quipment to see if anything is going to fail is standard practice. What better way than to have everyone using the site to run it through the motions.

The testing stages are long over for the simulcast cell.
Where are we getting this "simulcast cell" terminolgy from? If this were a true multi-site simulcast arrangement I should be experiencing lots of "capture effect" signal battles from multiple sites like I have with Aurora up here. So far it appears to be a single site.
 

MMIC

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Which industry is that?

Let's just say "RF". :)

Exercising the quipment to see if anything is going to fail is standard practice. What better way than to have everyone using the site to run it through the motions.

While I have seen "burn in" tests, I have never seen anyone "burn in" a system by taking actual public safety traffic on both RX and TX. This simulcast cell is live, so any testing is long over.

Where are we getting this "simulcast cell" terminolgy from?

Because that's what it is.

If this were a true multi-site simulcast arrangement I should be experiencing lots of "capture effect" signal battles from multiple sites like I have with Aurora up here.

In Greeley, you are definitely not in the RF capture area of any of the sites on this system or Aurora's. Not by a long shot. What you were probably experiencing with Aurora was a time delay effect where the signals from the sites were reaching your antenna at different times. From Aurora to Greeley, this delay can be on the order of several milliseconds, so I am not surprised that you were experiencing this. Were you hearing this on the analog side or digital side of Aurora?

That question leads me to my next explanation of why you may not be hearing the time delay effect on the 700 MHz simulcast cell. With digital transmissions, effects like multipath or time delay will only manifest themselves as digital or degraded audio. You will not hear the "barrel roll" sound of multipath or time delay that is audible with analog transmissions with digital.

So far it appears to be a single site.

Well, if I can't convince you otherwise, that's fine. But i'm here to tell you that it is a three site simulcast. When the time comes that someone you believe more than me tells you that it is, be sure to send a reply message here to tell me that I was right ;)
 

jimmnn

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Wow does this guy have an attitude or what. Thanks for your most helpful input.

Holy Cow

Jim<
 
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