Edacs Anti-scanner Tones

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#1
I have an older EDACS system in my area. After each transmission there are 5 high pitched beeps that last 3-5 seconds. I heard this is to throw off scanners that can track EDACS. Now I quote this from another web site:
"And now we move on to EDACS systems. Known in the hobby community mainly for their obnoxious and aggravating "scanner-buster" beeps (which can be defeated with a couple of after-market gadgets for your scanner)"

Anyone know what these gadgets are?
 
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#2
I have an older EDACS system in my area. After each transmission there are 5 high pitched beeps that last 3-5 seconds. I heard this is to throw off scanners that can track EDACS. Now I quote this from another web site:
"And now we move on to EDACS systems. Known in the hobby community mainly for their obnoxious and aggravating "scanner-buster" beeps (which can be defeated with a couple of after-market gadgets for your scanner)"

Anyone know what these gadgets are?
Those beeps have no affect if you use a trunk tracker scanner configured for EDACS mode. This was an issue years ago with legacy scanners that could not track EDACS systems. You had to listen in a conventional scanning mode.
 
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#3
I remember those early systems played the data beep song to the tune of GE's commercials of the 70's and 80's GE, "We bring good things to life."

At the end of each transmission, you could hear that data sounding tune/tone. On some systems, the tune was painfully sloooooow however I heard other systems of the day where the tones of the tune played very rapidly.

Today, the tone is just a short pulsed tone of 5 beeps, no discernable tune.
 
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#4
Yeah, if they are bothering you, you're either not using a trunk tracking scanner that's EDACS capable,
or you couldn't be bothered to program it. Either way, you're way behind the times if you are even
noticing those annoyance tones.


Elroy
 
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#5
I have an older EDACS system in my area. After each transmission there are 5 high pitched beeps that last 3-5 seconds. I heard this is to throw off scanners that can track EDACS. Now I quote this from another web site:
"And now we move on to EDACS systems. Known in the hobby community mainly for their obnoxious and aggravating "scanner-buster" beeps (which can be defeated with a couple of after-market gadgets for your scanner)"

Anyone know what these gadgets are?
This is just silliness and lack of knowledge in part of the scanner community,
such that it is...

These beeps are a talk channel timeout sequence, a ligit part of the system
operation, nothing to do with defeating scanner listeners at all (except in the
minds of the paranoid).

Dave
 
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#6
I have a BCD396T and even with the latest upgrades I still hear these beeps. A lot of people do. You can still follow the system, but in the time it takes for the talkgroup to hold while the beeps are playing, you could be missing part of another transmission on another talkgroup
 
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#7
I only hear them sometime, when i get a low low signal.. And even then i dont hear them most of the time. Just them random low signal days ill get 1-3 in a row and thats it
 
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#8
Yep, it has no effect on me monitoring the only EDACS system by me on my PRO-2051, but I was wondering what they guy was talking about. I used to conventionally scan it on my old 895XLT and remember the tones. The 2051 cuts them off.
 
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#9
...Anyone know what these gadgets are?
To answer your question, before the days of trunktracking scanners there was a board which could be installed into certain scanners, which would detect those beeps and return the scanner to (conventional) scanning. I believe it was called GE-whiz, though I may not be remembering that right. You might try searching around usenet archives of alt.radio.scanner and rec.radio.scanner for more info.

I supposedly heard one of these after-market gadgets in use at a local wrecker's shop, but I didn't get to actually see it and my then-weeks-old Pro-92 was doing a lot better than it.

My local EDACS system used to have buzzing stepping through the vacant voice channels, assumed to be there to defeat scanners. Initially it was nearly continuous on one channel or another, pausing briefly only to change channels every five seconds. Later there would be a bit of a break before it resumed on the next channel. I recorded a WAV of it a long time ago; I still hear it in a different context, from time to time when someone doesn't quite properly connect. Back then it was way too regular to have been this, if the control channel was 1 then it would go 2-3-4-5-2-3-4-5-2-3-4-5 for hours/days/weeks/months on end, to be interrupted only by actual comms on the system. I haven't scanned the system conventionally in years so I don't know if it is still there.

If there is another reason for that buzzing, I would love to know it.

Jim

EDIT: found a link: GE/Ericson trunking scanners? (rec.radio.scanner) Looks like this one came from Scannermaster. As others have written in this thread, and despite what is written in that link, please don't mistake those beeps as being purely to defeat scanners, although that side effect may have been quietly marketed to prospective system owners/operators.
 
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GTO_04

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#10
To answer your question, before the days of trunktracking scanners there was a board which could be installed into certain scanners, which would detect those beeps and return the scanner to (conventional) scanning. I believe it was called GE-whiz, though I may not be remembering that right. You might try searching around usenet archives of alt.radio.scanner and rec.radio.scanner for more info.

I supposedly heard one of these after-market gadgets in use at a local wrecker's shop, but I didn't get to actually see it and my then-weeks-old Pro-92 was doing a lot better than it.

My local EDACS system used to have buzzing stepping through the vacant voice channels, assumed to be there to defeat scanners. Initially it was nearly continuous on one channel or another, pausing briefly only to change channels every five seconds. Later there would be a bit of a break before it resumed on the next channel. I recorded a WAV of it a long time ago; I still hear it in a different context, from time to time when someone doesn't quite properly connect. Back then it was way too regular to have been this, if the control channel was 1 then it would go 2-3-4-5-2-3-4-5-2-3-4-5 for hours/days/weeks/months on end, to be interrupted only by actual comms on the system. I haven't scanned the system conventionally in years so I don't know if it is still there.

If there is another reason for that buzzing, I would love to know it.

Jim

EDIT: found a link: GE/Ericson trunking scanners? (rec.radio.scanner) Looks like this one came from Scannermaster. As others have written in this thread, and despite what is written in that link, please don't mistake those beeps as being purely to defeat scanners, although that side effect may have been quietly marketed to prospective system owners/operators.
I had a G-Whiz module installed in my SC150 and it worked very well. The GE jingle actually was put in to aggravate scanner listeners, but the FCC made them drop that. One local PD was ordered to drop the jingle when they applied for more frequencies. The faint beeps that you ear today are not specifically anti scanner tones though. Once in awhile I will hear a long and loud buzz on my local EDACS system and I was told that happens sometimes when the controller gets overloaded. It does not happen as often as it used to.

GTO_04
 
L

LS1_TA

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#11
This is just silliness and lack of knowledge in part of the scanner community,
such that it is...

These beeps are a talk channel timeout sequence, a ligit part of the system
operation, nothing to do with defeating scanner listeners at all (except in the
minds of the paranoid).

Dave
B I N G O !!!!!! :p
 

Thayne

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#12
I understood the "buzzing" that is actually rotated on the LCN's was to verify that each LCN was operating within specs, and is used by the system for that purpose. Real EDACS radios don't open the audio for those "Buzzes" The beeps actually hold the channel open to make a conventional scanner stay there for a few seconds while the conversation is off to the next LCN, thus pissing off those listeners without a trunking scanner. I could be FOS, but some EDACS guru will probably chime in--
 
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#13
The GE jingle actually was put in to aggravate scanner listeners,
GTO_04

Another bit of misinformation...the GE Gingle, which I well remember hearing on a local
system and the Toronto EMS system, was a carry-over from the precursor to EDACS
(GE 16-plus). It also was a timeout sequence; the fact that it had a cutsie sound doesn't
change the fact that it had a function, other than deterring listeners. Don't know the
FCC history behind the change, but it wouldn't have to do with scanning.

The reason for a timeout is to keep a converstion on an assigned channel for as
long as possible without wasting channel time with dead air, for the sake of
efficiency. Timeout too short, the conversation needs to get bounced around too
many channels, each with its setup overhead and delays, also not good.

That rec.radio.scanner piece is ancient, referring to manual scanning of systems.
The first EDACS scanner (BC245XLT) was just coming out around that time (11 years
ago...). You'd expect to hear all sorts of noises that the real systems users would not.

Dave
 
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#14
I understood the "buzzing" that is actually rotated on the LCN's was to verify that each LCN was operating within specs, and is used by the system for that purpose. Real EDACS radios don't open the audio for those "Buzzes" The beeps actually hold the channel open to make a conventional scanner stay there for a few seconds while the conversation is off to the next LCN, thus pissing off those listeners without a trunking scanner. I could be FOS, but some EDACS guru will probably chime in--
I think you're right, at least some systems have a "diagnostic thingie" a sort of dummy TG
that cycles through channels to continuously check them. Moto systems key up each voice
channel once a minute for one second to check TX.

However, I believe the users are not "off to another channel" while the beeps
are in progress. They are waiting for either the timeout to expire (nothing else
happening), or the conversation to resume on the same channel. It should not be
hard to verify this.

Anyone who hears beeps on a EDACS scanner is likely to have an LCN/channel
ordering problem, or a problem with signal level.

EDACS can also carry data groups, telemetry I presume also, which could account
for some of these annoying sounds. I don't deny that anti-scanner features could and
may have been added to particular systems, but I think their presence is greatly
exaggerated.

Dave
 
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W1RHW

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#15
I had a PRO-95 issue with that. For some reason, no matter how well you programmed the unit using just the radio itself by hand, EDACS never scanned right on it. It had to be done through the Starr Soft's Win95 for it to work for me. I never understood why that was, but that is just the way it worked.

Of course I ditched the PRO-95 once I fell in love with dynamic memory allocation and the idea of not having to listen to every talkgroup on Motorola systems.
 

nd5y

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#16
However, I believe the users are not "off to another channel" while the beeps
are in progress. They are waiting for either the timeout to expire (nothing else
happening), or the conversation to resume on the same channel. It should not be
hard to verify this.
That isn't how it works from what I can tell and have read about.
In every EDACS system I have seen (which is only about 4 or 5) the talkgroup voice channel changes or rotates for each individual transmission. There isn't any voice channel hang time like a motorola system or conventional repeater. Each time a user keys up a "new" voice channel is assigned. The beeps are a turn-off code. It is a 4800 Hz tone if I remember right. When the user radio unkeys, it sends a data burst on the voice channel input freq. which causes the controller to start making the beeps on the output. When the user radios hear the beginning of the first beep they immediately return to the control channel. Somebody who actually runs or maintains an EDACS system can correct me if I'm wrong.
 
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#17
The EDACS beeps are indeed 4800 Hz and are used by "real" EDACS radios to signal the end of transmission, and to return to the control channel. The lack of low speed data (if you listen carefully with headphones, you'll hear a low 'burble' in the background of any analog transmissions) is also a cue for the EDACS radios that signals the end of transmisson, return to the control channel.
The fact the beeps are repeated 4 or 5 times (depending on the software revision loaded into the base station) ensures that the radios in the field have maximum chance to detect the end of transmission even if at the edge of coverage area. Its just fortuitous that these beeps annoy conventional scanner users - it wasn't purposely designed to achieve that end.

Likewise, the 'buzzsaw' sound is indeed a LCN test - again not intended to specificly annoy scanner users, but it does end up having that effect. This test can be set to various intervals, including continuously cycle through the LCNs immediately one after the other.

I can't say about the old GE-jingle, that's pre my time & experience.

The GE-Wizz already mentioned above made listening to EDACS systems on conventional scanners much more pleasant. I made my own design with an LM567 tone decoder IC. About 8 components and it worked a treat, though it was harder to install in some scanners than others.
This has been far surpassed by the modern breed of EDACS trunk-tracking scanners anyway.
 
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#18
EDACS beeps

This belief about the series of beeps are in part to disrupt monitoring is absolutly bull-crap. If you aren't convinced, why would GE and now MA/COM give a hoot?? No other mfg. has any beeps or tones for that purpose. That's why transmissions are scrambled. If you disagree with this................I has a bridge in Machinaw City, Mi that I,m willing to sell you !! Maybe this "myth" should be presented to "Mythbusters"
 

W1RHW

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#19
Someone said on another post, that American freedom results in us with the ability to listen to what we want as long as it is not cellular, or intentionally scrambled (i.e. FBI) frequencies.

If you didn't hear it right there, you can always go pick up the recordings at your dispatch office as they are required to do it by law (public record). Unless you live in NY state at which point it is illegal unless you have a reason for having the scanner such as Ham license.
 
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#20
I currently operate an EDACS system that was first installed in 1993. Classic GETC code ver.10 was running when the system was delivered and installed. This software had the GE-Jingle after each working channel call. The 16+ GE Trunked System was now called EDACS but many documents had 16+ on them. The very next version of software that we installed no longer had the Jingle.

The beeps now heard from a conventional receiver after each working channel call is signalling to the radios that the call is finished. There are several reasons that someone might hear buzzing on a working channel with a conventional receiver. You might hear a system generated "TEST CALL." This call is part of the test unit that will fail a working channel and remove it from use if everything is not working properly. You could also hear a data call. A longer buzzing type sound could be a digital voice call, Provoice or otherwise. The last thing that I know of is something called "SCRAMBLED DATA CALL." This is something that can be activated at whatever selected rate that the administrator selects and will rotate around each working channel repeater, not currently assign a call, to generate a buzzing sound that disturbs and distracts someone from scanning the system with a conventional scanner. I have been to almost every GE / Ericsson-GE / Comnet / M/A-COM training class offered in Lynchburg, Va and have never heard any other use for the "SCRAMBLE DATA CALL" other than to disrupt scanners. This is not something that they talk alot about but it has been mentioned over the years. Now that Trunk-Tracker Scanners have replaced conventional scanners, this is never mentioned. I think that everybody here is correct depending on what sound they are talking about.
 
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