When Did Trunktrackers Become Legal To Manufacture?

[JohnnyGalaga]

If I remeber correctly, I remember hearing a rumor a long time ago that when Uniden first came out with the BC235 Trunktracker they got sued by Motorola because it could track their systems. Was this true?

Wouldn't you have to violate patents to sell a trunking scanner? How did Uniden get around that? And what about EDACS and LTR later on?

They say there's never gonna be a ProVoice scanner because it's proprietary, but weren't Motorola and EDACS control chanels proprietary?

If Uniden managed to legally sell Motorola and EDACS capable scanners, then shouldn't there eventually be a way to make a ProVoice scanner?

[Voyager]

Originally Posted by JohnnyGalaga

If I remeber correctly, I remember hearing a rumor a long time ago that when Uniden first came out with the BC235 Trunktracker they got sued by Motorola because it could track their systems. Was this true?

Wouldn't you have to violate patents to sell a trunking scanner? How did Uniden get around that? And what about EDACS and LTR later on?

They say there's never gonna be a ProVoice scanner because it's proprietary, but weren't Motorola and EDACS control chanels proprietary?

If Uniden managed to legally sell Motorola and EDACS capable scanners, then shouldn't there eventually be a way to make a ProVoice scanner?

Uniden found a loophole in the patent, and went on to patent THAT as well. Others (such as Optoelectronics and GRE) found other loopholes such as using the Slow Speed data on the voice channel, but that form of trunking never worked real well since the Slow Speed data is missing the last bit, so it can't differentiate adjacent TGs. Apparently, the patent on ProVoice is pretty air tight.

Joe M.

[garys]

The issue was more copyrights on the software than patents. Copyrights have longer life spans and are more of a legal challenge to bypass. That being said, Uniden, or more specifically Greg Knox figured out how to decode the Motorola data stream without using any of the Motorola copyrighted material. He reverse engineered the process, IOW. He sold the technology to Uniden who incorporated it into the 235.

Two guys, Terence Brennan and Sean Sullivan, did the same thing for EDACS and sold that process to Uniden. Brennan used to have a site with the story of how they did it, but I haven't been able to find it for a few years.

Similarly, if someone can figure out a way to decypher the Pro Voice audio without using MA/Comm's proprietary processs they might be able to sell it to Uniden or someone. Unless of course MA/Comm claims that it's encrypted. Which I think they actually have covered with the ESK data stream. Then again I don't follow that, so my opinion could well be wrong.

Gary

[garys]

I hate to reply to my own message, but Brennan and Sullivan in fact have two patents on their technology. The Dec 2000 edition of Popular Communications has a story, written by Sullivan, of how they did it. If anyone has a copy, I'd love to see it.

Gary

[northzone]

This article appeared in a 2000 edition of Monitoring Times, and was written by Terence Brennan (KC4YDM) & Sean Sullivan (KC4YES).

Trunked radio systems have changed the nature of public safety communications over the past decade. Unlike conventional radio systems, where each agency has a dedicated communications channel, trunked systems pack numerous channels onto a small set of frequencies. Computers allocated frequencies in real-time to individual conversations or transmissions, and microcontrollers in agency radios automate the frequency switching that is needed. Scanner owners were left behind by this new technology.

In 1999, Uniden introduced the first scanners that could scan one of the two major trunked radio standards, EDACS (Enhanced Digital Access Communications System). The story of the development of EDACS-tracking scanners begins eight years ago, near Cape Canaveral, FL at news/talk radio stations WTAI. News director Wayne West had a strong personal and professional interest in monitoring Brevard County's radio system. In addition to his journalistic interest, he worked part-time as a sheriff's dispatcher, and his wife was also in the sheriff's department. When the county installed a new EDACS system in 1992, he found the new signals impossible to monitor.

One of us (Terry Brennan) was chief engineer at WTAI, and West asked if there was any way to monitor an EDACS system. Although the frequency-hopping characteristic of trunking was a serious handicap, there was actually a more serious problem when using a conventional scanner -- a variety of spurious signals unrelated to actual system traffic or operations. Loud beeps made it unpleasant to leave a scanner at a normal volume setting, and an unnecessary carrier at the end of the transmissions made scanners "lock" on useless frequencies. Brennan modified the radio station's scanner to eliminate the most irritating of these unwanted signals.

Brennan, as a long-time scanner listener himself, thought about ways to help other scanner users deal with the challenge of EDACS radio reception. He created a new and more sophisticated circuit to dynamically minimize the disruptions of monitoring an EDACS trunked radio system, designed to be installed in any scanner. With this 'G/Wiz' circuit operating, reception was like listening to a conventional system again, although all of the agencies were still mixed together. this proved to be very popular with local TV crews, hobbyists, and volunteer firefighters, and it is still sold nationally through Scanner Master.

The next step, which was much more complex, would be to design a system that would let users selectively track different agencies within an EDACS system. This would require computer control, based on the reception of the "control channel." One frequency in every EDACS system is devoted to a continuous transmission of digital data, and EDACS radios use this information to know which agencies are transmitting on which frequencies.

In early 1996, Rich Barnett at Scanner Master asked Brennan if he could create a technology to track EDACS transmissions. This was an exciting challenge. Starting from scratch, Brennan analyzed the signals sent by the EDACS "control channel." Developing such a system was no simple effort, since there was no public information on the encoding of the control channel, and the format was not obvious. In his minivan, using a 486/33 MHz desktop computer with a sound card, Brennan digitally recorded transmission samples from different EDACS systems around the U.S., noting exactly what the system was doing during each sample. Capturing certain significant, but rare events, like emergency button activations, took patience. As data was collected from numerous systems it could be correlated to observations.

Like Codebreaking

The process of deduction was like codebreaking. He wrote software to translate the audio to data, and then to interpret and analyze the data. Eventually he understood the system well enough from observation alone, that his software could 'read' recordings of the control channel and print detailed logs of system activity. At this time, one of us (Sean Sullivan) became involved in the project. Sullivan was in his junior year at Amherst College, working toward a degree in computer science and astronomy. As Brennan started to unravel the data format, he asked Sullivan to write a computer program that would track the system in real time. The program began as a passive display, showing the talkgroups active on each system frequency. Talkgroups were shown in the AFS format, a notation based on Brennan's observations of the EDACS binary data format, which grouped various agencies and fleets in specific patterns.

There were no EDACS systems near Amherst, located in rural western Massachusetts. The nearest systems were about 50 miles away in Worcester, MA, and Hartford, CT, and the signals were very weak. We found that there were a few odd and very localized "hot spots" around town where signals were much stronger. One such spot was next to a railroad bridge near the college, and another was behind a local mall. We worked for hours in Brennan's minivan parked in the Massachusetts wind and snow. Inside the van, we sat buried in radios, cable, papers, and computers, with a Yagi antenna facing out the window, taking observations and interactively writing and debugging software. Software is not always created at a tidy desk.

Controlling The Radio

As we crafted a reliable reception system, the next step was to control the radio. Brennan built demodulation hardware that worked with a PC-programmable radio (a Yaesu FRG9600), and Sullivan wrote a set of software tuning functions to control the radio. Despite the fact that Sullivan was working on his senior thesis at the same time, we finished the prototype in mid-1997. The resulting 'G/Trac' software and hardware accurately tracked EDACS systems. The system was very nice, but most scanner users would find it inconvenient to carry a laptop computer everywhere. Our goal was to make EDACS tracking widely available in a scanner.

After talking with various scanner manufacturers about our technology, our group reached an agreement with Uniden in 1998 to add EDACS tracking to the TrunkTracker series. This was a natural match. Uniden's product managers and senior executives understood the importance of trunking in the future of scanner technology, and they had already developed the first Trunk Tracker scanner capable of receiving trunked systems using the Motorola standard, which is different from EDACS.

Spring 1999

For the next year, we collaborated with engineers at Uniden at Dallas and Japan to refine the EDACS tracking technology and integrate it into a new radio design. We were both living in Boston, and we found a good signal reception location near MIT for the nearest EDACS system (in Worcester, MA). In contrast to other test locations we used, we found that it was pleasantly inconspicuous at MIT to have a minivan filled with electronics and a Yagi sticking out the window.

In May of 1999, we took the prototype BC245XLT to the top of Mt. Wachusett, and heard it smoothly track three different EDACS systems. The first EDACS tracking scanner was a reality. In the summer of 1999, the BC245 came on the market. This was followed by the Pro-94 and Pro-2052, sold through Radio Shack. The Uniden BC780XLT is to be released this year. After all the time and effort involved in deciphering the transmission format and developing a tracking system, it is very satisfying to see the technology reaching a broad market.

The availability of trunk-tracking scanners is not only valuable to radio hobbyists, but also to public safety professionals who use the equipment to stay aware of activity in nearby towns that use trunked systems, or to keep in touch with their own agencies while off-duty. Indeed some of the most enthusiastic users are volunteer firefighters.

Trunking: Here To Stay

We all know it's here to stay, and makes for efficient use of the spectrum, since multiple agencies can use a small number of frequencies. It allows for a lot of flexibility for each agency, since there are a virtually unlimited number of talkgroup codes available. And now, what once looked like a serious danger to the future of scanning has been conquered, and the hobby has moved into the age of trunked radio reception.

[JohnnyGalaga]

And thus several millionaires were born. Very interesting article! One thing I've always liked about trunking scanners is that they let hobbyists get even with the bastard 2-way radio companies who tried to take our hobby away. I used to live in Manatee County, FL which had one of the country's first EDACS systems. For years I couldn't listen to a darn thing with my scanner, and everybody's brother was on that stupid system.

I've always wondered if the EDACS tones and random buzzing noises served some important technical purpose, or if they were just designed to intentionally lock up people's scanners.

Companies like MA/COM and Motorola are the biggest RAPERS of governments in my opinion, with al their fangled high-priced digital systems. Wouldn't it be neat if the same reverse engineering could be done for 2-way radios? This would create some much needed competition against big companies like Motorola with all their UNETHICAL business practices..

[garys]

Northzone, thanks for posting the article.

As to becoming millionaires, they are probably better described as thousandaires. Even with a license fee on each scanner sold, if they have one, the scanner market isn't that big.

Gary

[Voyager]

Originally Posted by northzone

In 1999, Uniden introduced the first scanners that could scan one of the two major trunked radio standards, EDACS (Enhanced Digital Access Communications System).

Uniden introduced the first TrunkTracker, the BC235XLT, in 1997 not 1999, and would trunk only Motorola systems (and then only trunked - no conventional while trunking). It did not track EDACS. That was added to the BC245XLT TrunkTracker II, the second Uniden portable, in 1999.

Also, there were three major trunking standards at the time - Motorola, EDACS, and LTR.

Joe M.

[SlipNutz15]

very good article and very nice information to know. Props to those men who took a lot of time and energy out of their lives to figure out that stuff and overcome a lot of hard coding

[2112]

Originally Posted by JohnnyGalaga

I've always wondered if the EDACS tones and random buzzing noises served some important technical purpose, or if they were just designed to intentionally lock up people's scanners.

Actually, there are tones and noises that serve both purposes. The one I remember most was a scanner-defeating tone in use on an EDACS system in northern Ohio in the late 80's/early 90's... it was a serious of tones after each transmission that sounded like the old GE jingle "We bring good things to life". That before the advent of data-blocking and trunktracking... so that made even trying to listen to that system a real PITA.

Originally Posted by JohnnyGalaga

Companies like MA/COM and Motorola are the biggest RAPERS of governments in my opinion, with al their fangled high-priced digital systems.

I don't know exactly how you could feel this way... the companies aren't forcing the governments to purchase them. As long as the governments provide a market (read: are willing to buy), the proliferation of digital systems will continue. And this is a good thing... such advancement makes better usage of the spectrum that is becoming increasingly crowded all the time.

Originally Posted by JohnnyGalaga

Analog already is interoperable.

Not if you don't have an analog radio on the same bands, in the same mode, and running the same encryption and/or trunking schemes as the radios you want to talk to.

Analog is widespread... because we've been using analog technologies for a long time. That doesn't necessarily make it interoperable. Like it or not, wideband analog is becoming a dinosaur in a land of much more efficient technologies. Those that think everything should remain analog remind me of hams who can't *believe* that the FCC allows non-coded hams to have licenses.

A long time ago... AM broadcast radio was widespread. I reckon we should never haved messed with that new-fangled FM broadcast radio thingy.

[Astrak]

So how did GRE get EDACS tracking, did they buy it from Uniden?

[N_Jay]

Originally Posted by garys

. . . Similarly, if someone can figure out a way to decypher the Pro Voice audio without using MA/Comm's proprietary processs they might be able to sell it to Uniden or someone. . . .

ProVoice uses a DVSI vocoder under license.

Where Motorola and M/A-COM sell radios and patent things along the way, DVSI does nothing but develop intellectual property to sell, so I doubt they left any loopholes.

[N_Jay]

Originally Posted by JohnnyGalaga

And thus several millionaires were born. Very interesting article! One thing I've always liked about trunking scanners is that they let hobbyists get even with the bastard 2-way radio companies who tried to take our hobby away. I used to live in Manatee County, FL which had one of the country's first EDACS systems. For years I couldn't listen to a darn thing with my scanner, and everybody's brother was on that stupid system.

I've always wondered if the EDACS tones and random buzzing noises served some important technical purpose, or if they were just designed to intentionally lock up people's scanners.

Companies like MA/COM and Motorola are the biggest RAPERS of governments in my opinion, with al their fangled high-priced digital systems. Wouldn't it be neat if the same reverse engineering could be done for 2-way radios? This would create some much needed competition against big companies like Motorola with all their UNETHICAL business practices..

SRDD (Same Rant Different Day)

When you have worked for against and with these companies you have a very different perspective than when you watch from the outside.

If it were not for these companies you would not have two-way radios to listen to!

[N_Jay]

Originally Posted by 2112

Actually, there are tones and noises that serve both purposes. The one I remember most was a scanner-defeating tone in use on an EDACS system in northern Ohio in the late 80's/early 90's... it was a serious of tones after each transmission that sounded like the old GE jingle "We bring good things to life". That before the advent of data-blocking and trunktracking... so that made even trying to listen to that system a real PITA.

That was "Mark-V" (Mark-5) trunking not EDACS.

It was tone based, and needed a tone the decoders would not try to decode to send the units back to the control channel (like Reverse PL burst or DPL Shut off tone).

The silly GE jingle was probably some engineer with some spare time and not even a part of the specification.
(I doubt they cared about scanner listeners at all)

Later they had to change it to a steady tone as someone at the FCC defined it as "music".

[Dubbin]

Wow, it sure seems like trunkers have been around for longer then 9 years.

[b52hbuff]

Originally Posted by garys

Two guys, Terence Brennan and Sean Sullivan, did the same thing for EDACS and sold that process to Uniden. Brennan used to have a site with the story of how they did it, but I haven't been able to find it for a few years.


Gary

is this it?

http://gtrac.ztn.net/

[DickH]

Originally Posted by 2112

... I don't know exactly how you could feel this way... the companies aren't forcing the governments to purchase them. As long as the governments provide a market (read: are willing to buy), the proliferation of digital systems will continue. And this is a good thing... such advancement makes better usage of the spectrum that is becoming increasingly crowded all the time.

No, they don't force the municipalities to buy, BUT they give fancy presentations to people who are not radio-knowledgable, telling them things like, "you are going to lose your freqs., your radios won't work after a certain date", etc., etc. They also make exagerrated claims of what the new systems can do. Much of it is hype. And the gullible people who make the decisions just eat it up. The knowledgeable people, if there are any in the municipality, don't find out about it until it's too late.

[Dubbin]

Originally Posted by b52hbuff

is this it?

http://gtrac.ztn.net/

I doubt it since it doesn't tell the story, unless they since removed it.

[N_Jay]

Originally Posted by DickH

. . . . The knowledgeable people, if there are any in the municipality, don't find out about it until it's too late.

Then the "knowledgeable people" are either not doing there job, or really are not as "Knowledgeable" as they think they are!

[JoeyC]

Originally Posted by DickH

No, they don't force the municipalities to buy, BUT they give fancy presentations to people who are not radio-knowledgable, telling them things like, "you are going to lose your freqs., your radios won't work after a certain date", etc., etc. They also make exagerrated claims of what the new systems can do. Much of it is hype. And the gullible people who make the decisions just eat it up. The knowledgeable people, if there are any in the municipality, don't find out about it until it's too late.

Yadda yadda yadda.... What is the difference between this and any other salesman? The job of the salesman is to sell the product, otherwise they are ineffective and lose their jobs. Same holds true for the guy selling cars, cellphones, stereos, avacados on the street corner.

It is the responsibility of the consumer to know what he is purchasing. If your municipality "don't find out about it until it's too late" they they didn't do their homework and probably shouldn't be in the position to spend the city, county or states money in the first place.