Why and when should us scannists enter a DCS code?

John_M · #1 (**permalink**) 04-27-2005, 08:19 PM

There are two particular EMS Dispatch frequencies in my area that have a DCS code assigned to them. When I enter these codes I can only can here the dispatcher's transmit with no warning tone. I also cannot listen to the incoming transmissions. These incoming transmisssions each have their own CTCSS code. I want to hear everything including the warning tone so I do not enter the DCS code, nor do I enter any CTCSS codes.

What is the reason for these two DCS code? I can't see why us scannists would want to enter them unless you only want to hear the Dispatchers transmits with no warning tone.

I will slow down sometime guys but just don't feel like slowing down at this particular point in time.

KCChiefs9690 · #2 (**permalink**) 04-27-2005, 09:33 PM

Well, say there are 2 towing companies on the freq of 150.845. The companies are Big Bob's Towing, and Uncle Ted's Towing. They both will have a different CTCSS code so they won't have to listen to a driver from the other company since they are on the same frequency. If a scanner listener wants to listen to Uncle Ted's Towing, they would only program their CTCSS code to prevent hearing Big Bob's Towing. You won't have to wonder which company is talking since you only programmed their CTCSS code. I can't answer about why the tones won't come through though.

PJH · #3 (**permalink**) 04-27-2005, 09:48 PM

Its just the way the system is setup. Where I use to work, EMS pagers worked off of the Police channel. We didn't want our cops to be blasted by tones in the cars (cops radios are inheartenly turned up loud to start with...and when you send QCII tones thru them, you can feel your teeth rattle).

So, what we did is transmit the tones without a PL with the following voice with PL so the cops knew where they were going to go (as they went to EMS calls).

99% of radio pagers do not have a PL feature, so its transparent for everyone involved.

Where I work now, we transmit without PL, but we have a PL or DTMF access to get into the dispatch center..so if you enter a PL on that channel, you will only hear the voice units.

I am sure there is a good reason for what they did. This type of setup is not as common as it once was, but there are plently of these around.

scan-pa · #4 (**permalink**) 04-27-2005, 10:03 PM

Same here in Dauphin Co PA. for our EMS

Pager tones sent with CSQ, then all Voice uses PL Tone. That way the radios can be set to only open on either the pager tone or the pl tones.

Joseph11 · #5 (**permalink**) 04-27-2005, 11:51 PM

Quote:

Originally Posted by PEN311

Same here in Dauphin Co PA. for our EMS

Pager tones sent with CSQ, then all Voice uses PL Tone. That way the radios can be set to only open on either the pager tone or the pl tones.

I wouldn't believe that if I didn't see that happen to me today. I was monitoring some Burlington County, NJ frequencies today and on the EMS dispatch frequency, the pager tones were CSQ and the dispatch had a PL. Odd thing, I've never seen anything like that before.

Voyager · #6 (**permalink**) 04-28-2005, 12:01 AM

Quote:

Originally Posted by Joseph11

Quote:

Originally Posted by PEN311

Same here in Dauphin Co PA. for our EMS

Pager tones sent with CSQ, then all Voice uses PL Tone. That way the radios can be set to only open on either the pager tone or the pl tones.

I wouldn't believe that if I didn't see that happen to me today. I was monitoring some Burlington County, NJ frequencies today and on the EMS dispatch frequency, the pager tones were CSQ and the dispatch had a PL. Odd thing, I've never seen anything like that before.

Standard practice is to NOT transmit a CTCSS during paging. In reality, many don't follow that guideline. In fact, most don't. The two tones can mix and set off other pagers unintentionally.

Joe M.

PJH · #7 (**permalink**) 04-28-2005, 09:59 AM

Quote:

Standard practice is to NOT transmit a CTCSS during paging. In reality, many don't follow that guideline. In fact, most don't. The two tones can mix and set off other pagers unintentionally.

Joe M.

Huh? How you figure? That I would like to see some documentation on!

AlexC · #8 (**permalink**) 04-28-2005, 10:13 AM

How about I just set the record straight and tell you how exactly they are doing it.

The two channels you are talking about are 155.295 and 154.310 (EMS and Fire 5) if I'm not mistaken. EMS uses 3 simulcast transmitters on the east side of the county (where there are predominatly only EMS agencies not tied to fire depts). Fire 5 uses 5 simulcast transmitters throughout the county.

When they replaced the old transmitters with Quantar's, they implemented a DPL for fire and ems (not disclosed here). They upgraded the transmit sites to do "true simulcast" since the old system really didn't perform this. The new microwave system with fiber backups (i believe) allowed them to finally do DPL.

When all the county ems/fire agencies go narrow band, they will use the new DPL. Thankfully, they strip the tones out of it, as it makes for a nice and quiet dispatch channel.

Now. The current system requires a PL to talk to the dispatcher. County agencies monitor this channel in CSQ, so to hear other units and the EMS dispatcher.

I'll refrain from giving more information out, but I am very firmiliar with the whole system.

John_M · #9 (**permalink**) 04-28-2005, 10:47 AM

I kinda like the warning tones. I think there are different warning tones for different emergency situations with the Fire dispatch
channel. Am I wrong about this?

AlexC · #10 (**permalink**) 04-28-2005, 10:48 AM

Quote:

Originally Posted by JMedley_1

I kinda like the warning tones. I think there are different warning tones for different emergency situations with the Fire dispatch
channel. Am I wrong about this?

Each agency has their own set of towns. Some fire agency's have 16 different sets of tones.... yes... 16...

They are used to trip pagers/fire station alerting systems throughout the county.

John_M · #11 (**permalink**) 04-28-2005, 11:07 AM

I don't think I am going to waste my time trying to figure out
the the different fire tones.

AlexC · #12 (**permalink**) 04-28-2005, 11:08 AM

Quote:

Originally Posted by JMedley_1

I don't think I am going to waste my time trying to figure out
the the different fire tones.

Believe me, it's not worth anything to even think about wasting the time to figre it out.

John_M · #13 (**permalink**) 04-28-2005, 11:23 AM

When are Uniden and GRE going to come out with scanners that you can enter more than one CTCSS code for a frequency? Some of us would like to do this maybe me included.

jimsokol · #14 (**permalink**) 04-28-2005, 11:50 AM

The only solution is to program the frequency into more than one channel and use set a different dcs for each. This way you can still individually lock them out. How would you just lock out one of them if you could enter more than one dcs or pl for a freq???

...jim

John_M · #15 (**permalink**) 04-28-2005, 01:45 PM

Enter them all except the one you don't want to hear. This would slow the scan speed down a little though if the scanner has to stop on a frequency and check for several different tones.

AlexC · #16 (**permalink**) 04-28-2005, 01:46 PM

Quote:

Originally Posted by JMedley_1

Enter them all except the one you don't want to hear. This could slow your scan speed down a little though if the scanner has to stop
on a frequency and check for several different tones.

Just monitor the channel in CSQ. There's no reason to use PL on those dispatch channels.

John_M · #17 (**permalink**) 04-28-2005, 02:03 PM

Your right Alex there is no reason to use any tone on our two
local EMS freqencies. I have these two channels set to FM mode.

There are some instances that Scannists might want to enter more than one CTCSS code.

Is DCS fairly new?

AlexC · #18 (**permalink**) 04-28-2005, 02:04 PM

Quote:

Originally Posted by JMedley_1

Your right Alex there is no reason to use any tone on our two
local EMS freqencies. I have these two channels set to FM mode.

There are some instances that Scannists might want to enter more than one CTCSS code.

Is DCS fairly new?

No. It's been around for a while. Do some google searching for it, I'm sure you can find the information your looking for easily there.