RACOM -----again

[Haley]

Ok , I THOUGHT i was being smart by adding a bunch of sites to my scan ranges. I finally realized that there is a lot of overlapping freq. and I am in an area that gets a lot of overlap!

Anyway, might be dating myself a bit. When I used to listen to an EDACS system before trunking scanners came along, you would hear the beeps after the call ended. I used to just program the freq. into my Pro-51(talk about LONG squelch tail!!!!), and listen to pieces of conversations. Of course RACOM was much less busy back then.

Now that I have put in some more sites (some well know large ones, and some obscure small ones), I get those beeps at the end of some of them-----certain towers. So since I got the info out of the database, does this mean some of them are incorrect? Maybe wrong LCN order? I do hear conversations off of these sites, like I said though some have the beeps at the end. Maybe I have a setting on/off that shouldnt be? Any thoughts, thanks Mike

[Radioman96p71]

Are you hearing the entire beep sequence of 5 beeps or does the scanner switch back to CC after the first one? If it makes it all the way thru the sequence and waits for carrier loss to switch then yes, you have a LCN out of place. Its interesting that you always hear the end of a convo, not just static. Odds are you will catch no carrier more than the beeps but that depends on the site and what LCN is wrong i guess.

The other possibility is some scanners detect the end of transmission poorly. In a M/A Com radio, the radio is configured to decode the low speed data on the voice channel to follow calls even when their are calls in progress, hence how priority scanning works with a TRS, but more importantly, it uses the frequency of the trailing beeps to tell it when the convo is over. Thats why you will never hear it on a 'real' radio unless in a low signal area and it misses the first one. Scanners on the other hand are more primitive and their decoding of the EOT beeps are hit or miss. I know my 780XLT is kinda crappy and sometimes it will miss a beep or 2 before it actually drops the call and switches. So that might be what is happening with you too.

What site is doing it the most and can you se what LCN does it most often?

[Haley]

I do hear the whole series of 5 beeps. I will watch and see which channels and towers do it the most often. Is it possible that some of the new sites I put in, may have some (but not all)of the same freq. causing them to be mixed up on other sites? For example 2 sites have the first 5 LCN the same (or any combination), and the next 5 different, or vice-versa. Would that explain the beeps though? I will watch more , and see if I can catch a pattern.


Were you listening to the Marshalltown site this morning? The marshalls showed up on there! I had to leave so I didnt get to listen any more, that is the first time I have ever caught them up here. Also got the FT.Dodge prison coming over the Marshalltown test site. Must be the weather! Mike

[Dak48]

Originally Posted by Haley

Also got the FT.Dodge prison coming over the Marshalltown test site. Must be the weather! Mike

Or... someone from the Prison could be in the area of the test site and their radio has affiliated with it. This happens in Lincoln NE quite a bit when Norfolk PD or Sheriff's office is in the Lincoln area. You can hear every call just as if it were all local.

Racom is a pretty amazing network I think, I can program in my local frequencies for Lincoln, and set up talkgroups for Lincoln, Omaha, Norfolk and Seward, and occasionally pick up Life Flight choppers being dispatched in Omaha, some 50 miles away.

It's not propagation that is making this happen, rather it is site affiliation, which is what makes Racom so darned slick in my opinion.

[Haley]

Dak48, you are right-----it cant be propagation. I hear radios from all over the RACOM network everyday, I am sure its because I live in the "home office" so to speak! It must be the test site I have programmed into my search. I also think on the bigger networks you have a better chance of hearing lots of activity outside the area. One thing is for sure, RACOM makes for some interesting monitoring. I have heard the US Marshalls 3x today off the Marshalltown site------thats probably my catch of the year! Mike

[Radioman96p71]

US Marshalls are pretty active in the morning during the week, at least on the Des Moines site. I was listening to them off and on today too, sounds like they are searching for a fugitive in the area up here.

[Haley]

Wirelessly posted (BlackBerry8330/4.5.0.66 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/189)

Adam do they ever use their VHF freq. Around here? Or just the local systems? I usually have my Pro96 searching for digital signals in that range, but never hear anything around here. Mike

[Radioman96p71]

I honestly can't tell ya! I wasn't aware they had one actually. I hear them enuf on the RACOM net i just figured thats all they used!

[Haley]

They have a few simplex VHF high freq. (their nationwide ones). Some are APCO25, and some are analog. They also use FBI freq.---- sometimes. Didnt know if anyone used them in the Des Moines area or not. They can pretty much use any freq. in the Federal band (162-174MHz). , thats why I just set up my 96 to search that band. I will admit----I never hear any federal stuff in central Iowa! But its a way to justify ANOTHER scanner to my wife. Mike

[Radioman96p71]

Originally Posted by Haley

They have a few simplex VHF high freq. (their nationwide ones). Some are APCO25, and some are analog. They also use FBI freq.---- sometimes. Didnt know if anyone used them in the Des Moines area or not. They can pretty much use any freq. in the Federal band (162-174MHz). , thats why I just set up my 96 to search that band. I will admit----I never hear any federal stuff in central Iowa! But its a way to justify ANOTHER scanner to my wife. Mike

Hahaha, hey that works!!! I scan it every once in a while. I have yet to hear a blip on it but maybe someday ill catch something. I have more fun monitoring the DEA on their new RACOM talkgroup XD

[Haley]

DEA? I am curious now! Is that TG 1818 in the database? The ATF TG is different right? Not that I am close enough, but assuming I was (I realize its probably encrypted), would any of the Trunking scannners I have ( Pro92,96, or 246t/346xt), be able to decode the TG? No voice, just the TG. I have never been anywhere to test something like that out. Sorry for all the questions, Mike

[Radioman96p71]

The ones I have seen them using are 468, 478, 479, 480, 481, 482, 486 and 800. All ProVoice.

Narc Ops is 1818, Narc Car is 1819, AEGIS digital non-encrypted. ATF Ops is 1824 analog.

I can't say much but there was a significant amount of activity this last week or so that included all the above and some Marshall Co digital GIDs. All of which was confirmed with a newspaper article stating the departments involved. Made for a VERY interesting day of monitoring!!!

[Radioman96p71]

Not sure if your scanner will show the talkgroup or not actually. On my 780XLT if i just set the scanner parked on the control channel not in trunked mode, active GIDs will display on the screen but it wont try to track them. If you are serious about watching activity on a TRS, eTrunker is the way to go. The information it displays all in one place is second to none. Unitrunker is an even better option as it runs via sound card on a 'normal' XP or Vista machine. Searching out new talkgroups and seeing the hidden stuff is painfully easy. If you get the motivation to give it a go, let me know I can help you get it all running!

[Haley]

Thanks for the info and offer! If I take it that far (etrunker), I will let you know. That sounds like the way to go. Now if I can just talk my wife into a nice PSR600, or 996XT----you know for the etrunker. Thanks, Mike

[Radioman96p71]

LMAO, if she needs a reference have her call me I got your back :P

[IowaBrian]

I too get the 5 beeps from time to time I think it happens on the Black Hawk County Freq's on the Cr tower. But not all the time. Reminds me of Kansas City crap when you don't have the scanner loaded but are just searching and storing, you always get the beeps there. I have My GRE500 loaded with cr tower and all groups from all states from this datebase.

[Radioman96p71]

I'm not real familiar with Uniden scanners, but I think I may know what you are experiencing. My 780XLT used to do it way back when and I never really gave it too much thought till you guys started talking about it. I think it has something to do with how the scanner detects the end of transmission.

Mine would do it the most in this scenario:
Scanner is listening to a voice channel and the calle ends, scanner goes back to the control channel. At the same time as the other call, a different call was happening that is also in the scan list. But ends at almost the same time as the previous call. The scanner tunes to the voice channel a split second too late, misses the EOM on the call and has to go thru the beeps until the carrier drops and the scanner realizes it missed the end of the call.

Another time it happened was when someone would quickly 'kerchunk' the mic, bringing up a call but closing it almost immediately. The scanner tunes to the voice channel as fast as it can but misses the critical EOM, and assumes it is listening to a call until the carrier drops.

Like I said, not sure exactly what method scanners use to detect the end of the message, whether it be low speed data, tone drop or what but it seems pretty obvious it doesnt use the beeps like the professional radios do or it would drop the call as soon as it receives the first one. I would think with the technology already there to decode CTCSS/DCS it would be a matter of coding in a routine to check for that tone frequency and drop the voice call when recieved. Or use that in conjunction with the existing method to eliminate false-positives.

Just my $.02, made sense in my head this morning when i read it haha

[Haley]

IowaBrian, I would agree that it seems to be off the CR tower(s), and more often than not seems to involve the Black Hawk co. TGs. Although I get the beeps off the Waterloo tower sometimes also.

Adam, what you said makes sense. When I hear the beeps, its seems to be when there is alot of traffic on the above towers, although occasionally it can happen on any of them. Its strange, like I said in an earlier post, the only time I have really ever heard the beeps, is when monitoring a trunked system with freq. programmed as a conventional channels.

By the way did you hear 04-060 today?

Mike

[Radioman96p71]

By the way did you hear 04-060 today?

Let me convert that to DEC and ill let ya know lol

[Radioman96p71]

DEC 560, havent seen that at all today on the Des Moines/ Pleasnt Hill sites. What did they have to say?