Important Question!

[Toledo_EMS_FD]

Quick Question

I am fairly new to using Trunker / E-Trunker, so correct me if I am wrong!

But I see a LOT of people asking about data slicers and how some work and some dont and some are superior to others. But what I would like to know is why noone uses the BUILT IN data slicer every trunking scanner has? I have three scanners, a 780XLT, Pro-2052 and Pro-91 all with the data slicer tapped and it works great! I get nothing below 98% accuracy and that is living 20 miles from the TX site! I mean, Uniden spent a LOT of time and effort designing the best data slicer they could to make their scanner better than the rest, so why not use it?? Anyways, sorry about the rant, just thought that this approach would make more sense...

Comments welcome!

73, KCØGIK

 

[WyoDuner]

More info please. How are you extracting the trunking data and interfacing it to your compute? This is the first I have read of somebody doing this.

 

[Toledo_EMS_FD]

Really? wow, its very easy! Actually just as easy as tapping the audio discriminator! The tap on the 780 is outlined on a website that I have now forgotten, I will look thru my history for it. The 2052 was very easy, the tap is actually labled data out! It interfaces DIRECTLY with the com port, no interfaces or other mumbo jumbo. In fact, i hooked the output from the data slicer to pin 6 on the scanner / comp connector so i can use the same scanner to monitor also! The Pro-91 was a little more difficult, call me insane, crazy whatever, but I hooked pin 5 GND of the COM port to the scanner ground, then with a wire going to pin 6, I just prodded the IC's watching for activity in slicer.exe. Call me lucky, but in 30 seconds I found the tap! The same preocess works for any radio im sure, i will get the number off the IC and post it when i get it back apart. After doing these 'mods' if you will to all three scanners, they all work perfectly and all give me 95+ signals in almost all conditions!

 

[rdale]

Since the Pro96 has the only ready-to-run data slicer, and the only scanner that does it for 9600 baud systems, wouldn't that be the 'ultimate'?

 

[Toledo_EMS_FD]

Im not familiar with the PRO-96 but yes, theoretically it would be able to decode just about all of them!!

 

[EricCottrell]

Hello,

I use the internal data slicer on a couple of the unidens. On the BC780 there is even
a spare RS-232 driver. I like the data to come out of the serial port.

I also modified the BC-245 but it has to be in remote mode to output. The downside is the keyboard is locked in remote mode on the BC245.

73 Eric

 

[WyoDuner]

Ok, this is interesting. I can't believe that I never read about this. Would love to hear more about it and/or some links.

 

[pro92b]

This information has been available for a while. See for example http://strongsignals.net/access/content/mods.html article 14 and Scanning USA magazine for June 2000.

Note that the tap point does NOT provide RS-232 compliant signal levels. It may or may not work with a given computer. It is also possible to provide better filtering with your own design since Uniden is constrained by parts cost in their design.

 

[WyoDuner]

Thanks Pro93b but that's just a discriminator tap??? I was under the impression from the posts in this thread that we were talking about tapping a DATA output not a DISCRIMINATOR output. Heck, most of my radios have discriminator taps - that goes to one of my data slicers which then take the baseband audio and using an op-amp at full gain drive 1 to 3 pins of a serial port high or low which is then interepreted by the application in question to derive data.

So the question remains, is there a place to tap actual data from any of these radios which can be sent directly to a serial port thus bypassing the need for a separate data slicer????

 

[pro92b]

It's not a discriminator tap. It is the output of the data slicer in the radio. Keep in mind that this internal slicer was designed to interface with the microprocessor in the radio, not an external computer. It doesn't really put out the right voltage but will work anyway in many cases.

 

[WyoDuner]

Ok... However the reference you cited is for a discriminator tap, not a data slicer tap unless I'm missing something here.

Know of any references to non-discriminator taps - the kind with data, not baseband audio??? This really has me intrigued and I would really like to see some good data on the subject.

I have been able to find anything doing web searches. Plenty of info on external data slicers that use a discriminator tap but not a single reference to tapping a scanner's internal data slicer (if a scanner in fact uses one).

 

[Sanscanman]

Try this for the BC780

http://myweb.accessus.net/~090/bc-780xlt.html#disctap

This shows both the slicer and the Discriminator tap points for the 780.


Hope this helps

 

[WyoDuner]

Thanks Sanscanman... That was the type of infor I was looking for.... Hmm... Makes a guy wonder if the data slicer output puts out just the control channels data or other data modes???? i.e. could it for example output ACARS "data" that would be readable with an application that would read the same data from an external slicer....

 

[cainst]

Toledo_EMS_FD,

I have a Pro-2052 that I'm using in conjunction with a Pro-2026 to scan both Motorola & EDACS systems. Can you give a little more detail as to how you can use the Pro-2052 to capture the data from the control channel plus monitor the system?

Thanks,
Steve.

 

[feta92]

My question is has any one tried this on the pro-96? If so is it worth while?

From what I am reading this software decodes transmission of runs to MDT's correct please correct me if I am wrong. If this does I would like to find out about getting my pro-96 done.

Thanks
Jason

 

[Toledo_EMS_FD]

I will have to photograph the tap point that i used, but it is labeled on the main side of the PCB. I cannot remember the exact name (sorry, its been a little while!) but it was right behind the display backlight. There are two taps there, one for the data, the other i'm not sure about. Sorry about the flaky details, i will dismantle it again when I get a little time and take some photos and the whole deal. The problem with the tap point I found on the 2052 is that it only works while in trunking mode, the tap I found on the Pro-91 works to decode any data it receives no matter where it is or what mode its in. Which makes it really handy cuz then i can do am conventional scan of all the freq's in the TRS, then when the CC changes, it goes right to it.

To all that may be interested, I built a VERY nice antenna based on the coaxial collinear design. It is tuned to receive around the 860Mhx area and has 15db of gain OMNIDIRECTIONAL!! This thing picks up stuff from over 65 miles away while maintaining at least 90% accuracy on etrunker. Best of all, it was built completely with coaxial cable! Just put it inside a peice of PVC and its good to go outside! If you want details on how I made it, give me a buzz...

Hope thise helps!!

Adam

 

[cainst]

Adam,

I have been playing around with my Pro-2052 and found the tap points you are talking about. I was able to tune in a control channel for my local EDACS system and was able to run it into the eTrunker with success. The tap point is labeled TD. The question I had was, how do you track the data and monitor it with the same Pro-2052 as you discussed earlier in this post.

Thanks,
Steve.

P.S. I would be interested in the antenna design.

 

[SCPD]

how do you track the data and monitor it with the same Pro-2052 as you discussed earlier in this post.

You normally need to use two radios and two serial ports. If you have a second serial port, plug in your computer controlled receiver. Read the docs on how to configure ETrunk to use the PRO-2052. If you only have one serial port, you will need to build a special Y cable to allow the slicer and PRO-2052 to share the same port. Note that eTrunk does not support single-radio tracking, you do need two radios for this to work.

Why? As soon as the radio left the control channel to monitor a voice channel, the program no longer knows what's active on the system. Worse, it doesn't even know when the current conversation has ended so as to switch back to the control channel.

-rick

 

[cainst]

Rick,

Thanks for the info. You confirmed what I already believed. I have been using the Pro-2052 with a Pro-2026 and it's been working great. When I saw the earlier part of the post, my hopes were up that there was some way of doing it with on radio. I've been trying to get the equipment reduced so I can easily carry it back and forth to work along with all the other stuff I have to lug along.

On the other hand, would it be possible if you where controlling the scanner while in trunk mode and selected the talk groups instead of tuning to particular frequency? Of course this would require modifying the controlling portion of the program.

Thanks,
Steve.

 

[markgrutz]

T4win and PRO96

I looked around and didn't find the answer I wanted in one place, so after much searching around this great site I got an answer..... and here it is:

There is a pin labeled (TP4) on the board between the volume and squelch knobs, using this for the center pin and ground for the outer shell of an audio cable, T4WIN decoded the control channel info from the PRO96 w/o any hassle. I plucked a bunch of info in just a few minutes... sad that I don't have a 2nd scanner to actually hear what I am seeing

Mark