Monitoring multiple ARMER sites

[kthelen]

Hello all!

I'm not new to radio listening, but am new to monitoring ARMER, and hoping to learn from the experiences of others here.

As I understand it, one can anticipate a city/town/county's talkgroups to be carried on sites within the affected area, and possibly other additional sites as radios subscribed to said talkgroups roam about and affiliate.

So, in order to receive all the talkgroups I'm interested in, I anticipate needing to receive from six distinct sites, each being various distances/directions from where I'm located.

The sites of interest range from 1-17 miles away. Therefore, I expect I may need to use directional antenna(s) to receive some of the more distant sites reliably.

A few things I'm wondering...

- Does the State publish any technical info on the sites' antenna patterns, ERP, etc.; or are there any predictable/typical specs? Would be useful in figuring out whether the sites I'm interested in are even likely to be receivable from my location, and what sort of heights/antennas/etc I'll need to plan for.

- For those of you with very active receive setups, do you tend to use multiple scanners and divide the talkgroups among them, or do new scanners offer features (ie. some form of priority scan) that could reduce the need?

- Since I'm likely going to be facing some challenging receive scenarios, and also working in a fairly high RF environment, can anybody recommend (or warn against) particular models of scanners that'll be fairly robust, RF-wise (sensitive, selective, not prone to overload or other undesirable behavior)?

Also, is anyone aware of any scanner(s) that offer some form of IP-based remote listening and control that works well? There are a couple of even further-out sites that I know will be impossible to receive from my main location, but would be easy catches from another site where I have IP connectivity going back to the main location with plenty of bandwidth. I know I could just stream the audio back, but losing the metadata would limit the usefulness.

TIA,

Keith

 

[ofd8001]

If you scour this forum for older posts, you'll see some coverage maps posted.

I'm only familiar with Uniden scanners and here is how they work. You have X sites programmed and a list of all the talkgroups you wish to monitor. The scanner stops on a site and "listens" to the control channel. When channel grants occur, the scanner looks to your scan list. If the "granted" channel is in your scan list, the scanner does its thing and you hear the transmssion.

If there is no channel grants for talkgroups you have programmed, then the scanner proceeds to the next site, repeating the process. Then on to the next site, etc.

Given the overall interaction of the entire ARMER system, each particular sub-system does not have a very large footprint. For example, the Mall of America is right at the very edge of the Minneapolis sub-system coverage area.

Since the scanner spends about 1.5 - 2.0 seconds monitoring each site it receives, judicious selection of which sites to monitor is recommended. For example, if you are in Minneapolis and only want to monitor Minneapolis fire, there's no reason to monitor Hennepin East. All the Minneapolis fire traffic will be heard on Minneapolis, even if the Minneapolis unit ventures into Bloomington and affiliates with Hennepin east. In that case, Minneapolis fire traffic is carried on both the Minneapolis and Hennepin sties.

The ARMER system is a tough one to get your arms around. It is very complex.

 

[mrmeowmittens]

I would start with where you are located and what you wish to monitor. Some things are carried on multiple sites and you may need to receive less sites than you think

 

[ofd8001]

The ARMER system is complex, it's challenging to give specific advice without knowing exactly where (city/county) that you'll do most of your monitoring.

I take it from the original post you are still looking to purchase a scanner. We've been visiting family in Minnesota for many years and I have used several models of scanners to monitor the ARMER system. The ones I'm most pleased with are the Uniden 436 and 536 models.

 

[peq387ab]

I have been motioning the ARMER system for about 6 years in outstate Minnesota. I'm taking it that if you are talking about running into RF problems, must be down towards the twin cities metro area in guessing.

To answer your question on antenna height, I do have a list somewhere that gives antenna heights on different towersites. I can certainly look for it here and share that.

For a map this link is of the townsites in Minnesota. https://dps.mn.gov/divisions/ecn/pr.../Armer Site Map/armer-site-map-2016-12-01.pdf

Depending on where you live some towersites are a stand alone towersite and others are Simulcast. Simulcast are more common in the twin cities area and other larger community and a few counties. This means that several towers are essentially linked together and broadcast over all. More commonly in my area there is a towersite which will broadcast stuff in that area like law and fire mains that are forced for the county and affiliation onto that tower. ARMER system can be quite complex.

As far as scanners go, I personally use Radio Shack Pro 197s and GRE PSR 500's. I do know some that are using dongals tied to a computer.

Would be glad to give you more insight or information. ARMER system is fun to monitor from listening to decoding with Trunker