Scan less, hear more

[rrobinso84]

So I've had my SDS200 for about four months. Been working on favorite lists, avoiding sites I can't receive, etc. I also have two SDRs running on two local digital P25 systems. After a recent RRDB update for my area, I thought, why not try a full database scan? I did, let it run overnight thinking how many new channels will I record?

Checked the next morning, and guess what? I had less than 20% of my "normal" traffic that night!

Vivid evidence of the "scan less, hear more" mantra you may hear a lot around here!

 

[mass-man]

which is why more than one scanner makes for more interesting listening.

 

[iMONITOR]

I scan local PD on one scanner, and local FD/EMS on another for that reason. Other scanners and receivers are used for other purposes depending on what I want to accomplish at any given time.

 

[Benkasey]

Yes, I found that out with my SDS100. I have multiple favorite lists with 5-8 frequencies in each. I select one list at any given time. It's suboptimal to scan too many frequencies at once. There is a mathematical formula that would tell you the optimal number of frequencies to scan to hear maximum content, based on variables like activity. That's beyond my capability.

Even though I have 3 SDR dongles, what I do sometimes is use the "slice" feature of SDR Sharp to listen to multiple transmissions at once. Right now I have 4 city PDs sliced. Most of the time there's no overlap, so it works well. It's also fun to tax your brain to try and follow multiple transmissions simultaneously. A few years ago when we had a wallop of a storm I had all three dongles going with multiple slices each -- PD, airport, city maintence, etc. Man that was crazy.

 

[west-pac]

Most people have no idea how many conversations they miss, even with only monitoring their local P25 site. Take the number of frequencies on your local P25 site, subtract one (the current control channel), all of the frequencies that are left can have a conversation on them at the same time. On small sites, it may be 3 or 4 conversations that are possible at the same time; or large sites it might be 15 conversations at the exact same time..... your scanner can only listen to one. During every public safety emergency you are missing more traffic than you are hearing; even during slow times you're going to miss traffic occasionally. This is really evident by using an SDR and watching Unitrunker. You can see when each person keys-up their radio and see which frequency they are assigned, and then see when other people key-up their radio at the same time and get assigned a different frequency. It might be your local police and fire talking at the same time, or your local jail operations and public works talking at the same, or it might be all 4 groups talking at the same time. Regardless, your scanner can only listen to one of those conversations at a time.

 

[belvdr]

Only program potential control channels into your SDS as well. No need to scan extra frequencies if you don’t need to.

 

[ecps92]

Only program potential control channels into your SDS as well. No need to scan extra frequencies if you don’t need to.

All depends on the Flavor of the TRS being scanned. Harris any channel can be the CC, Motorola can be anywhere from 1 to 4 CC's

 

[JethrowJohnson]

I just scan my county and sometimes surrounding counties for mutual aid incidents, and my main channels are priority status, and because of the way my county's set up, it doesn't work very well to have those interrupt other traffic, so I use Priority DND, and I rarely miss anything important.

 

[belvdr]

All depends on the Flavor of the TRS being scanned. Harris any channel can be the CC, Motorola can be anywhere from 1 to 4 CC's

Right and with Harris you’d program in all potential control channels, and that happens to be all frequencies. .

 

[rrobinso84]

Most people have no idea how many conversations they miss, even with only monitoring their local P25 site....

Agreed! It's well worth picking up an SDR or two and a good digital radio app (I'm using DSD+ Fast Lane) just to see and understand how much is going on behind the scenes in a digital trunked network! I've learned so much more about how they operate with that setup than I have with the scanner that's easily 20x the cost!

 

[bob550]

I'm going to scan less and less and hear more and more until I'm scanning nothing and hearing everything! Think of the money I'll save on my next scanner!

 

[rrobinso84]

I'm going to scan less and less and hear more and more until I'm scanning nothing and hearing everything! Think of the money I'll save on my next scanner!

I guess that's what Broadcast-ify is all about, right? But seriously, I'm almost there with a $25 RTL-SDR left wide open on my busy local P25 site!

 

[dave3825]

Most people have no idea how many conversations they miss, even with only monitoring their local P25 site.

Not even just P25 sites. Anytime the scanner is on any freq, conventional or trunked, its not scanning other freqs and is missing everything else going on.


If one took 5 sdr dongles and 5 instances of DSDPlus, one could monitor and record 5 P25, Nxdn or Dmr conventional channels simultaneously and playback thru Scanner Audio Recorder. Dongles with some trunking software out there lets you record multiple talkgroups simultaneously also.

Sds 200, $700 = listen to one thing at a time.
5 Rtl dongles, $150 = listen to alot.

 

[bob550]

With multiple scanners and agencies transmiting simultaneously, the limitation here is that we still only have one set of ears and one brain to process all the noise. Pretty soon, it's like trying to follow one conversation in a crowded room. Ideally, you would have to be recording each for playback during any lulls.

 

[dave3825]

With multiple scanners and agencies transmiting simultaneously, the limitation here is that we still only have one set of ears and one brain to process all the noise.

​

Universal Scanner Audio Player, Trunking Recorder, Trunk Recorder and Rdio Scanner, just to name a few eliminate that limitation. Yeah, with a major event with multiple agencies involved, it would take some time but having it all recorded let's one playback at a comfortable rate.