$500 Later, I Finally Learn!

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ntnahed

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Jan 25, 2004
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Austin, Texas. Actually born here!
I bought a BC396T last year, it never really received too well here in Austin, got boring, put it aside for a while... come back to it recently, after much VERY frustrating effort, it still receives like s--t, if at all. I recently bought a 796T, after a week of hoping for a little advice on the Texas forum, only to get a reply yesterday that the 396 and 796 are pretty much worthless for monitoring Austin. $500 poorer, but a little wiser through much trial and error and one helpful reply. Thanks, Moto.

So, I have a couple of new questions - Does ANYONE IN AUSTIN know how to make a 396 or 796 work in the Austin radio environment? If not, anyone have suggestions as to what radio WILL work here? I'm looking for a simple radio that is reliable in the Austin simulcast P25 environment.

I'm not exactly a newbie - been scanning off and on for about 20 years, including trunked systems in Tulsa and Seattle. I'm a free-lance photographer, and I also found a scanner very useful for avoiding traffic jams when I lived in Seattle. They've got some traffic issues here in Austin, too. Any advice will be appreciated!

One more question - anybody looking for a 396T or 796T for cheap?
 

soncorn

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Dec 1, 2003
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546
Location
Fort Worth, TX
You need to make sure the scanners are only receiving a signal from one of the simulcast towers. You can try the built in attenuation. Also you could try a poorer (yes I meant that) antenna, you could try no antenna. A more expensive option is a directional antenna that you point at only one tower.

Right now the problem is that you are getting signals from multiple towers at the same time with the waves being slightly out of phase and canceling some of the signal out which confuses the scanner.

The XT's have this problem too, just not quite as bad.
 

soncorn

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They have similar problems on the Starcom21 system in IL. Here is a thread where they talk about this problem and how it also affects the GRE PSR-500.

http://forums.radioreference.com/il.../115760-monitoring-starcom-gre-psr-500-a.html

Edited to add:

The very important post in that thread is this:
The GRE's aren't alone in this, the Unidens are just as bad, if not actually somewhat worse on simulcast sites. The word I have heard is that Motorola is using a different digital codec on simulcast sites and that when scanners are hearing multiple towers they tend to get garbled due to differences in the arrival times of the signals to the receiver.

I have had good luck with both Uniden and GRE scanners by reducing the antenna resource (attenuators, BOS versus external etc.) so that I only hear a single tower in the simulcast set.

Also remember that the sites around Springfield (the OP's area of concern) aren't even using simulcast, each site there is single-site. The only areas of StarCom21 that use simulcast are the several Chicago area sites, Peoria, Rockford and MetroEast.

Another very important post:
You're referring to ISI - Inter Symbol Interference, and it's exactly that, when the symbols (not bits!) get schmeared all over the place due to the signals arriving at different times. This can happen not only due to simulcast sites but also due to multipath.

When things get bad enough, bits get flipped.

From what very little I've heard on this topic from GRE, I think that they don't have error correction that's as good as, say, Motorola. It doesn't take very many wrong bits to make a narrowband vocoded data stream unintelligible, and the GRE will squelch when it realizes it's about to pump out garbage audio. That means a loss of audio, many times are a really critical time in a transmission.

Frustrating to say the least.
 
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ntnahed

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Jan 25, 2004
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Austin, Texas. Actually born here!
Thanks, SC!

I really appreciate the excellent advice, as well as the kind and generous help you gave me last year.
But it seems like my radios and the GATRRS system have "a failyuh to cumoonicate"...

I have a few questions -

I'm only loading one system at a time. I tried Central Austin on 700 mhz and got zilch. I tried the Simulcast 1 system (ONLY) and could receive bits and pieces in scan mode, but if I hit "HOLD" on a TG, I get no further transmissions. Any ideas? Seems to me multi signals shouldn't be a problem if I only have freqs for a single site loaded. Am I wrong?

I'm using Freescan, and downloading directly from RadRef. As I load the file to the scanner, I get a "1" in the error column. Any way to tell what the error is and how to fix it?

I'm only getting 2 or 3 bars on the signal strength meter with an 800 mhz antenna. I've tried the RS nascar stubby, which gets 1 or 2 bars, which seems to do just as well (or just as badly) as the 800 mhz stick.

I even met with Radio Pablo who has a 396t and monitors Austin. I copied his program, loaded it to my radio, and still had issues. Could there be a hardware defect? Maybe his radio works because he's living 20 miles south of Austin?

I'm going to try the 796 next - it did seem to get the AFD signal pretty well when they had the big fire on I-35 last week. I'm not the type to give up easily, but I've spent at least 20 hours so far, trying to get this 396 tuned in, with pretty much no success. I got the Uniden software for the 796, which leaves a lot to be desired. I'll probably try the ARC250 software for the 796...

If anybody in the Austin area has a radio that can reliably monitor the GATRRS system, I'd sure appreciate some input, ESPECIALLY if you're using a 396 or 796. In fact, I've got a C-note for the hero that can get them both reliably dialed in to the GATRRS system. Any takers?

And thanks again, Soncom. If you ever get down to Austin, let me know - it's ribeyes at The Hoffbrau, on me.
 

soncorn

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Dec 1, 2003
Messages
546
Location
Fort Worth, TX
I tried the Simulcast 1 system (ONLY) and could receive bits and pieces in scan mode, but if I hit "HOLD" on a TG, I get no further transmissions. Any ideas? Seems to me multi signals shouldn't be a problem if I only have freqs for a single site loaded. Am I wrong?

Even though it is in the database as one site, it is actually a simulcast site with multiple towers broadcasting the same signal, so you still can have multiple signals. You should try programming in the control channel frequencies for the simulcast 2 site also to see if you receive that better/worse.

I'm using Freescan, and downloading directly from RadRef. As I load the file to the scanner, I get a "1" in the error column. Any way to tell what the error is and how to fix it?

I can't help you with Freescan.

I'm only getting 2 or 3 bars on the signal strength meter with an 800 mhz antenna. I've tried the RS nascar stubby, which gets 1 or 2 bars, which seems to do just as well (or just as badly) as the 800 mhz stick.

Do you notice if the performance is better based on where the scanner is located in the house? Try moving it around (even small amounts) to try and find a position where it is only receiving one of the simulcast towers. The number of bars shown isn't as important as the quality of the sound from the scanner. The bars are great for a rural conventional system, but don't mean a whole lot on a modern simulcast system. I find that on the analog simulcast system here that moving my scanner a few inches can improve control channel decoding dramatically (that is what gets hurt by simulcast on analog systems, the voice channels don't seem to be as affected).

I even met with Radio Pablo who has a 396t and monitors Austin. I copied his program, loaded it to my radio, and still had issues. Could there be a hardware defect? Maybe his radio works because he's living 20 miles south of Austin?

Maybe Pablo can help you out more. Try his program, but with each of the simulcast sites programmed as separate systems to help you troubleshoot.

If anybody in the Austin area has a radio that can reliably monitor the GATRRS system, I'd sure appreciate some input, ESPECIALLY if you're using a 396 or 796. In fact, I've got a C-note for the hero that can get them both reliably dialed in to the GATRRS system. Any takers?

Meeting with someone will be your best bet to try and find a solution (or at least the best case performance.

And thanks again, Soncorn. If you ever get down to Austin, let me know - it's ribeyes at The Hoffbrau, on me.

Sounds good, if you make it up this way we can at least double check the programming, etc.
 

hiegtx

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Dallas, TX
I'm using Freescan, and downloading directly from RadRef. As I load the file to the scanner, I get a "1" in the error column. Any way to tell what the error is and how to fix it?
With FreeScan, the "1" in the 'error column' should be blue, with an underline.
Clicking on the 1 (or whatever the number of errors were) should give you a display of what the problem was. The most common ones I get relate to blank entries or other issues related to 'fire tone out', which I don't use anyway.

As far as the simulcast systems go, soncorn has pretty much covered the bases. Those are a problem for all of the scanner models. What seems to work for many users, is the suggestion to use a directional antenna, pointed at one, specific, tower, to minimize the multi-path signals that disrupting the scanner's ability to successfully track the system.

I've also noted some comments that the very latest firmware works better. But then there are those that insist that the version previous to that is actually best, for their specific system. That leads me to believe there may be enough differences in specific systems, that a 'one size fits all' approach in the the scanner firmware and programming may not work on every system. As we don't have any similar systems here in the DFW area, unfortunately I can't offer you a suggestion of what 'works for me'.
 

ntnahed

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Jan 25, 2004
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Austin, Texas. Actually born here!
Thanks, High and Son!

I'm still working on it...what I'm really looking for is something I can use mobile, for photos and traffic. I'll try the programs you sent, Son, I've got the Uniden software too. I'll let you know how it works out.
Thanks again, amigos!
 

motorola_otaku

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Here's something you can do with that 796: program the input frequencies for the Simulcast 1 site as conventional. Take all of the frequencies for that site, subtract 45, and program them in a bank in descending order as conventional frequencies. What that will get you is everyone in your immediate vicinity talking into the system; you won't hear replies from the dispatchers since they're talking directly into the system via consoles, but it'll still give you an idea of what's going on in the 'hood. You could even experiment with antennas to improve your "talk-in" range. Or, if you're in range of one of the IR sites, it should work okay for trunking them since they're not simulcast.
 

rockag41

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Oct 22, 2003
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San Antonio, Texas
I use ARC396Pro to program my 396. I have never had a problem picking up anything in the Austin area. Perhaps there is a glitch in the Freescan program. Just a wild guess. I don't know anything about Freescan.
 

ButchGone

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Jan 9, 2004
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Ringgold, Georgia
In Tennessee and Georgia I have found my 396t works better on P25 simulcast systems by setting the digital decode to Manual then selecting either 6 or 7 (mileage varies on system, location) for best/lowest error rate. If I leave digi decode in the AUTO mode reception is the worst. I have never been able to get any P25 simulcast system to behave right in the AUTO mode with the 396t.
A friend swears the GRE 500 does much better on digi simulcast systems but I have no experience myself, yet.
BG..
.
 

jetcitymantx

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Jul 3, 2006
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Location
Lewisville texas
Scanner

I was in Austin over the weekend using a Pro 106 and The P 25 Austin PD uses is Terrible, I was getting Every other word.I think the terrain has a lot to do with it? Lots of hills and trees and that digital signal is having a hard time getting through.....My 2 cents! also some of the area Radio stations were weak also, so I will Bet that Digital system in Austin is not liked By the PD or Fire!!
 

mtrac

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Jun 27, 2010
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Hi ntnahed,

I just picked up the same radio (BCD396T) and I'm having the exact same experience here in Austin! I actually found your thread while trying to figure out a solution. I'm a newbie so I wasn't sure what I was doing wrong but I loaded the bcd39t with FreeScan via radio reference just as you did. I'm still learning and need to reread the message here but will keep an eye on this thread. I'm going to look into the antenna as my ebay purchase included a longer whip antenna which may be making the issue worse from reading this thread.

-Matt
 

mtrac

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To followup,

As someone said a few messages back, putting things to Manual and 7 or 8 seemed to help (thanks). Also I switched to a smaller antenna AND turned Attenuation on for the system and things are much better. Of course I can't leave it on that depending on where I'm sitting in the house but at least it's something.
 
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