Need Help==PSR-800 P25 LSM Performance

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KC9NEG

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Hey, guys, I'm working with a PSR-800 here and monitoring this system:

Metropolitan Emergency Communications Agency (MECA) Trunking System, Indianapolis, Indiana - Scanner Frequencies

Yes, the infamous MECA system in all its LSM CQPSK glory. I've been providing a live RR feed of this system for a couple years now:

Marion County Police Dispatch Live Scanner Audio Feed

This isn't a "Brand U vs. Brand G" troll post--please, stick with me because I'm seeking help. I'm currently using a Uniden HomePatrol-1 to run the feed, and, well, you be the judge about the quality of audio on this notoriously-difficult to receive system. Mind you, this is with no special tuning other than installing a Diamond SRH789 antenna, set to shortest length.

I know I must be missing something, but I programmed the same TG's into the PSR-800 as my feed (9 PD dispatch channels only) and, all else being equal, the audio on the PSR-800 is horrible by comparison to the HP-1. By that I mean same location, same time. I've tried three antennae (stock ducky, RS 800MHz, and Diamond RH519--I'm somewhat of an antenna collector!) but I'm hearing mostly broken, garbled audio (and, interestingly, it seems to improve slightly when I'm actually holding the radio). The problems I'm encountering seem like those inherent to simulcast systems per this wiki article:

Simulcast digital distortion - The RadioReference Wiki

I've monitored this system for years, with much more success, using a PRO-96, PSR-500, and PSR-600 than the PSR-800 seems capable of. Is there anything I can "tune" with this radio? Any way to see the CC error rate? Is it possible I have a bum radio? I know GRE radios can (and, by my direct experience) do much better here. Any and all thoughts and suggestions from this community will be most appreciated.
 
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KC9NEG

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Another interesting thing to add:

My feed HP-1 is obviously in an ideal location (or the audio wouldn't be as good as it generally is). The same radio (HP-1) is nearly mute monitoring this system at my home about 5 miles east of the feed radio (which makes sense, because my home is more equidistant from many MECA towers than my feed radio). The PSR-800, however, receives a fair amount of garble audio at my home. So it seems the GRE radio is perhaps more sensitive (but can't seem to decode so well) whereas the Uniden just doesn't hear the system well enough to decode much of anything there.

When using the Global ATT function on the PSR-800 the radio goes mute.
 
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IowaGuy1603

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In the trunked radio systems tab on the radio software click on your system


Then below click on the system in the site information area

that highlites the error correction adjustment----change it to around low 70 high 98 and see if that helps


You can play with those numbers to get the best reception




The 800 is much more sensitive than the Uniden and actually decodes BETTER. You just have to have the settings correct.

If I am close to a site (simulcast P25) I often just us a paperclip as an antenna........or shield the ducky with my hand to attenuate the signal.............the 800 is very susceptible to other RF
 
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kikito

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We have a 700MHz Simulcast P25 system up here that both, PSR-800 and BCD396XT, do poorly as far as audio quality.
 

KC9NEG

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Thanks, guys... I ASSuME, IowaGuy1603, that you're referring to the "Data Decode Thresholds" values... I'm experimenting with those now...
 

KC9NEG

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I found this in the help file just now:

"On trunked systems with multiple transmitter sites, the GRECOM EZ Scan Digital Handheld trunking scanner will search for the best site.

The Data Decode Threshold settings are used to control the selection of the best site.

When a system is first enabled, the scanner will scan through the sites from the first one listed looking for a control signal. When one is found, the scanner will sample the data stream and calculate a decode rate based on expected data transmission rates. If the scanner finds a site that meets the high threshold value, it will use that site until the decode rate drops below the low threshold value. At that point, the scanner will attempt to find another site using the same process."

So it appears these settings won't help with single-site systems like the one I'm monitoring (actually MECA has two sites, but I'm only importing System 1 which is Public Safety).
 

KC9NEG

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If there is no way to monitor the error or decode rate of the CC and make adjustments which may improve it, I'll be forced to conclude that the PSR-800 is an inherently inferior radio (in comparison to the HP-1 and the BCD-996XT, as well as the PSR-500 and PSR-600 I've previously used) for monitoring this particular system.

Is there anything else I could be missing? C'mon, you GRE guys, I REALLY want this radio to work out!
 

IowaGuy1603

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Thanks, guys... I ASSuME, IowaGuy1603, that you're referring to the "Data Decode Thresholds" values... I'm experimenting with those now...

Yes................that is correct.


If there is no way to monitor the error or decode rate of the CC and make adjustments which may improve it, I'll be forced to conclude that the PSR-800 is an inherently inferior radio (in comparison to the HP-1 and the BCD-996XT, as well as the PSR-500 and PSR-600 I've previously used) for monitoring this particular system.

Is there anything else I could be missing? C'mon, you GRE guys, I REALLY want this radio to work out!

It might not be the scanner for you then It might be "inferior" for your purposes but it works fantastic for me.
 
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IowaGuy1603

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We have a 700MHz Simulcast P25 system up here that both, PSR-800 and BCD396XT, do poorly as far as audio quality.

They are very hard to monitor..................the system I monitor works pretty well using the numbers I gave earlier.

The big probelem with a simulcast system is getting a good line of sight with a tower..........Using a yagi pointed at that tower is the best way to "lock on" the signal.
 

KC9NEG

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The clear fact of the matter is that, side-by-side, the HomePatrol-1 is simply TROUNCING the PSR-800 when monitoring the subject system. I didn't expect this based upon experience with previous GRE models, and I want to make this radio work for my particular propose.

I appreciate the suggestion, however, those settings don't seem relevant to single-site systems like MECA 1.
 

mancow

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Thanks for posting this. It has made all the difference in the world for me with the 800. I went to the PRO197 and changed the noise threshold from 20 to 5 and that has seemed to help quite a bit as well with a large 700 simulcast system I am trying to monitor.


In the trunked radio systems tab on the radio software click on your system


Then below click on the system in the site information area

that highlites the error correction adjustment----change it to around low 70 high 98 and see if that helps


You can play with those numbers to get the best reception




The 800 is much more sensitive than the Uniden and actually decodes BETTER. You just have to have the settings correct.

If I am close to a site (simulcast P25) I often just us a paperclip as an antenna........or shield the ducky with my hand to attenuate the signal.............the 800 is very susceptible to other RF
 
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scannerfreak

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The clear fact of the matter is that, side-by-side, the HomePatrol-1 is simply TROUNCING the PSR-800 when monitoring the subject system. I didn't expect this based upon experience with previous GRE models, and I want to make this radio work for my particular propose.

I appreciate the suggestion, however, those settings don't seem relevant to single-site systems like MECA 1.

Can't speak for your location or other factors, but I am using the PSR-800 to monitor the Cincinnati LSM system from home and it's flawless. Even when I drive around the city it does an outstanding job on the system. I've also had the 800 in Indy on trips quite a few times and haven't experienced any issues other then minor drop out in some downtown locations. I had the opportunity to test an HP for a period of a couple of weeks and had exact opposite results as you. It wasn't near as good on the Cincinnati system. Different results for different systems/areas I suppose.

Playing with the decode rate does help. I use 70/90 and seems to work for me. You can also try locking out all but the control channel.
 

KC9NEG

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Can't speak for your location or other factors, but I am using the PSR-800 to monitor the Cincinnati LSM system from home and it's flawless. Even when I drive around the city it does an outstanding job on the system. I've also had the 800 in Indy on trips quite a few times and haven't experienced any issues other then minor drop out in some downtown locations. I had the opportunity to test an HP for a period of a couple of weeks and had exact opposite results as you. It wasn't near as good on the Cincinnati system. Different results for different systems/areas I suppose.

Playing with the decode rate does help. I use 70/90 and seems to work for me. You can also try locking out all but the control channel.

I will certainly try your last suggestion of locking out all but the CC. Thanks.
 

KC9NEG

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70/90 (or any other threshold settings) and L/O all but the CC didn't help a bit. Either this thing doesn't cut it for MECA or I have a bad radio. Either way, unfortunately, back it must go. I just don't get it...
 
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scannerfreak

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Sorry to hear it didn't work out for your specific situation. It's a great radio and has worked very well on MECA for me when in Indy.
 
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KC9NEG

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Could it be the difference between being out west (Brownsburg) vs. being downtown? Could it be a bad radio? It just doesn't work at all, and I sure don't understand that.
 

scannerfreak

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I'm not all that familiar with the area. When I'm in Indy most of the time it's downtown. When mobile I use an Antenex AB8065CTS and the RS 800. I can usually start picking up the system in the Greensburg/Shelbyville area (on the radio with the Antenex) where I get decent performance as I drive closer to Indy. When I start to hit downtown I do start see some minor drop outs as I drive around, but this is to be expected when mobile. I recently stayed at a hotel near the 465/Michigan Rd. area for three days and was receiving the system darn near flawlessly from my room using only the RS 800.

I doubt you got a bad radio, but I suppose it's possible. It's likely the typical issues you get with this system type. Doing a side-by-side comparison is tough to do accurately. You really need both radios hooked up to the same antenna, etc. I don't doubt you are having issues specific to your area/situation, I am only reporting what I've seen on MECA and the Cincinnati system; and based on that I wouldn't call it the radio not working on LSM systems. They are just very tough to receive. I would bet if you got a Yagi and fine tuned it you'd see the radio perform the way you want it to.
 

indyone

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I'm in the Indianapolis area as well and just picked up a PSR-800 a day ago. I'm having no luck monitoring the Indianapolis system. Everything is very garbled. I've tried adjusting the Data Decode Thresholds with no success. I'm really disappointed to say the least. My old pro-96 does just as well. I’m thinking I should have gone with the Homepatrol for this system. I might try to sell the PSR-800 and go with the Uniden. It can’t be any worse.
 
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