Morse CW identifier

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kruser

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Do trunked systems like the CSP have a frequency for them?
Did you mean do they have a CW ID for them?
Of course they have a frequency as that is one of the basic fundamentals of radio!

Then they most likely have some form of CW ID. It can be seen on a P25 system with programs like Pro96com.
I think but not positive that it is still broadcast in analog but it could be a digital CWID also. Can't say I've ever monitored a P25 sites CW frequency and listened in analog for an ID. I know the stations must still broadcast a CWID or some form of ID to be in compliance with FCC rules.
I just don't know if it is allowed to be done in a digital format or not.
Hopefully someone will pop in as I'd like to know that answer as well.
I also don't know how Pro96com decoded the CWID if it is sent in analog as I don't think the program can decode anything analog so maybe the ID is sent in both formats.
I do know it is only broadcast on one of the frequencies used for a given P25 system or site. They don't make them broadcast it on every frequency for an entire site.

If you get the CWID for a site, you can often get all the sites frequencies depending on how the site is licensed. Some sites are licensed under a State License or CAPRAD in which case finding all the frequencies in use can be hard or impossible especially if some are taken from federal allocations or taken from spectrum held by license holders of say a paging market area. Those can be hard to determine.
 
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coolrich55

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Reading a thread from Las Vegas and they say the new p25 system has its own TG for the CWID. What does CW stand for anyway?
 

n5ims

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Reading a thread from Las Vegas and they say the new p25 system has its own TG for the CWID. What does CW stand for anyway?
CW is short for "Continuous Wave", basically an unmodulated carrier. In this case, the information is transmitted not by modifying the carrier (varying the amplitude or strength of the signal for AM or varying the frequency of the signal for FM) but by simply turning it on and off in a specific pattern (e.g. turning it on for 1 time period, off for 1 time period, on for 3 time periods, then off for 3 time periods would translate into ". -" [dot, dash, or dit, dah, if you prefer] indicating the letter "A"). The time period depends on the speed you're transmitting at where slower speed code (5 WPM for example) would use a longer time period than faster code (20 WPM for example).

Now, it's often done when sending slower code to send each character at a faster speed, but extending the spacing between characters to slow down to the desired code speed. Basically, the longer time period between characters gives the mind time to recognize and translate. Many code tapes are encoded with the characters done at 13 (or 20) WPM speed and the spacing done to slow the overall speed down to the 5 WPM rate. This is done to help folks more easily increase their code speed once they've mastered the slower speed. It also helps decode the characters since the very slow speed can make it harder for folks to recognize the dots from the dashes (also a very long dash can cause the mind to start wandering). Doooooooot Daaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaash is actually harder for your mind to hear than Dot Dash.
 
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kruser

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Reading a thread from Las Vegas and they say the new p25 system has its own TG for the CWID. What does CW stand for anyway?
n5ims summed up the meaning of CW nicely. It's also simply known as Morse Code by many. Although CW is more a form of modulation (it confuses you here as it is an un-modulated carrier in its true form!) and morse code is, well, morse code. Morse code can be sent with several different types of modulation and the more I think about it, I imagine sending it digitally is perfectly legal as long as it is not sent encrypted.

That makes me wonder how the amateur operators ID when using modes like D-STAR. I think D-Star repeaters may drop to an analog mode and send the morse code that way but I've never heard the operators drop to analog mode and ID, they ID in D-Star mode. I'd imagine there is an FCC ruling that permits that.
I guess it's no different than ID'ing in SSTV mode where you send your call in the picture you are transmitting.
Never really thought about it before!

I have seen LTR systems designate a talkgroup, if you will, for the CWID but for most P25 digital sites, they do not designate a talkgroup per se but will set aside one of the sites frequencies as the designated ID frequency. That frequency often does double or triple duty as it is also used for digital voice and/or data when the CWID is not being sent.
I forget the legal code but the I think the CWID must be sent every 30 minutes on an active system.
And like in amateur radio use, it does not need to be sent at all if the system is silent such as a business system would be after hours. Some sites still send it regardless.
Here in Missouri when all they had was the low band analog system, the dispatcher announced the troops call sign at the end of EVERY communication. They did not say it every time they unkeyed the mic but said it each time they were done working with a trooper or finished up a point to point broadcast. Even though they now have a working statewide digital system, you still hear some of the dispatchers saying the old callsigns. I guess after years of saying it, it kind of grows on you! Most of the dispatchers in the state today are pretty good about not saying the call any longer unless they had also simulcast or worked with a trooper on the old low band analog system alone or along with the digital system which they plan on keeping the last I heard.

If you analyze the control channel datastream of a P25 site, the data will often indicate which frequency is designated as the CWID channel. Most control channel analysys software will decode the data into the actual call sign for you.
Some sites use any available channel for sending the ID when it is time while some sites designate a single frequency whcih is used for voice at other times.
And as n5ims pointed out, CW is really more like a form of modulation so calling a frequency of a P25 site the CWID channel may not really be the correct term as I know they don't use continous wave for the CWID on a P25 site but someone called it that and it stuck!
The letters CW are actually used incorrectly in radio a lot these days the more I think about it.
I guess if you wanted to be more technically correct, you would call it the morse code channel or the call sign channel or simply the ID channel although I think a lot of modern day radio techs would give you odd stares or write you off as some weird loony tune.

Then there is another term or abbreviation you will see often in the world of digital and analog trunked systems.
That being "RID". It originally meant "Radio ID" as each radio has one aand no two should be the same on the same system, especially in digital systems.
Somewhere along the lines, not long ago, that term seems to have been replaced by UID which essentially means the same thing or more specifically, the Unit or User ID.

Why the change in the abbreviation is beyond me but you can take a RID and self convert that to say "Ranger 35" if you so chose. So there will always be a RID that is incorrectly called the UID today. Many do text tag a given RID into something more easily indetified such as Ranger 35 as many modern radios allow for text tagging a RID into words.
The only problem with that is when radios break, or other users are allowed to use that same radio such as what could happen between say a day and a night shift. I know many spend hours figuring out who the user is of a given RID only to discover the next day that a whole other user is now using that radio and their text tag is no longer accurate.
It does work for agencies that let the users take cars and radios home and I suppose many find a lot of enjoyment in just figuring out who a user is and giving that RID a real name.
It is a neat feature in todays modern scanners but if you monitor an agency where the radios are shared amongst several users, text tagging each RID could be found the be a waste of time, especially on a system with thousands of users!
I'll admit that I do text tag some RIDs but only for the companies or public safety agencies I monitor where I know the radio users do not change hands. For some companies or agencies, I text tag the RIDs with a more generic name like say "fire commander". That works as the radio may be used by more than one person but it is mounted in a car that is only driven by the fire commander on duty at the time. Some people take it a step further and give that RID the users name only to discover that name may be the night commander and the day commander has a different name of course!
I guess it all depends on your interest in the hobby and how much free time you have.
I often listen from across the room so I could usually care less who is talking as I can't see the radio anyway but with the many remote apps today, you can almost see your radios display from anwhere.
That can make things fun, especially if you come from a time when all you had were channel numbers or light bulbs (or LEDs) indicating what channel you were stopped on and you had to know what frequency crystal you had installed in that channel.

There's of course a LOT more to it today than simple CW and RIDs!
I have no idea exactly how they do it on the Connecticut CSP system but that is the gist of it.
I guess the main thing is do what you like and have fun doing it!
 
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ecps92

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Depending on the system the Freq will vary, but yes there is a Morse Code ID Sent.

Motorola TRS was always the lowest Frequency

Now for a TG just for a Morse ID ? Odd, but not out of the possibilities, however
CW can mean different things in difference thoughts
CW = Continuous Wave
CW = City Wide
CW = County Western

Do trunked systems like the CSP have a frequency for them?
 
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