Madison County P25 TRS

[KK4JW]

Programming my 996XT with Madison County's P25 system, using FreeScan. I understand that in order to scan each zone properly, they both need to be programmed in as two separate systems under one group.

I've done this, and entered all of the frequencies as opposed to just entering control channel frequencies, as I'd read it could help with the actual scanning function.

However, I'm not seeing any fields to enter the other information such as "base frequency", "channel spacing", "Lo channel", "high channel", etc, as depicted under Misc. System Information.

https://www.radioreference.com/apps/db/?sid=6750

Do I just need to enter in all of the frequencies as I have done, and enter in the TG's I want to monitor and let the scanner do the rest? Or is there something else I need to enter as well? I'd be happy to send my FreeScan file to anyone familiar with this system if they'd graciously examine it for me.

Thanks!

 

[KK4JW]

I've tried programming only CC's, as well as a custom bandplan with Mot Custom/Reband Type II and still am not getting any results. I can hear CC activity if I manually select a CC, but am not picking up any TG's when in TG search mode.

I'm also getting a full S meter with the RS800 antenna. I've tried with and without the 20dB attenuator as well.

Anyone?

 

[VASCAR2]

I’ll chime in on this thread as no one else seems to be trying to help. My Daughter worked for Richmond PD as a Dispatcher while She went to EKU in 2004. Basically a little familar with Madison County, Richmond, Berea area.

With a P25 system you shouldn’t need an adjusted band plan. I’d think the data stream would transmit the baud rate and the scanner decipher the baud rate. I don’t remember if most P25 systems are 9600 baud or what is the specification. The information on the Radio Reference data base might be prior to 2009 before the release of the newer scanners. On Uniden Bearcat BDC996 you had to change the band plan after narrow banding. On the newer BDC996XT a band plan change was not required on P25. The P25 data stream was read by the scanner so you don’t need to modify the band plan.

I suggest you set up a new system set up as P25. Don’t change the band plan. I’d set up two tower sites and program all the frequencies for the north site on one site location. I’d then create a second site with all the frequencies for the south tower site location.

The Madison County P25 is a simulcast system and you might encounter problems with multi path distortion due to your scanners different distance to each atenna in the simulcast system. If the system is programmed correctly you should detect the data stream on the control channel. The control channel should give off the site number and system ID number.

Usually on multi site simulcast systems having less signal strength is better than a strong signal. Shortening the pull up antenna might help. If your very close to one transmitter site you might not encounter the multi path distortion.

I’ll keep watch on this thread and see if I can help you sort out any issues. To me the Madison County system should work like any wide area trunked system where multiple tower/sites are used over a large geographic area. If my opinion if the second site doesn’t work you could delete one tower/site and the system would be configured like a stand alone trunked system with only one tower with associated frequencies.

Madison County has always used the latest radio technology and I’d be surprised if the BDC996XT could not be programmed to work on the Madison county system barring a location problem associated with simulcast systems. Scanners don’t work very well on single frequency multi site simulcast systems. I looked at the data base but I don’t remember if Madison Co uses many encrypted talk groups which no scanner can monitor.

 

[KK4JW]

I've been toying with my P25 settings all morning/afternoon so far. I'm getting the best results thusfar with a P25 Adjust Level of 170, and a P25 Adjust Mode of 4 - OR - a P25 Adjust Level of 170 and a P25 Adjust Mode of 8.

I'm seeing the "ERR" readings in the 63-64 range.

Five full bars of signal - I'm pretty familiar with the tower locations in Madison County and there's one approximately five miles from my house. I'm using an RS800 antenna. I've tried turning the 20dB attenuator on also, and all that does is drops the signal strength.

I understand SOME of the TG's are encrpyted (Police) and that's fine, whatever. I'm finally beginning to hear some parts of transmissions though. The scanner will seem to pick up on a TG, decode the first word or two of a transmission, and then lose it.

I have a good CC lock also.

I guess I'll just keep tinkering with the P25 settings.

 

[VASCAR2]

I've been toying with my P25 settings all morning/afternoon so far. I'm getting the best results thusfar with a P25 Adjust Level of 170, and a P25 Adjust Mode of 4 - OR - a P25 Adjust Level of 170 and a P25 Adjust Mode of 8.

I'm seeing the "ERR" readings in the 63-64 range.

Five full bars of signal - I'm pretty familiar with the tower locations in Madison County and there's one approximately five miles from my house. I'm using an RS800 antenna. I've tried turning the 20dB attenuator on also, and all that does is drops the signal strength.

I understand SOME of the TG's are encrpyted (Police) and that's fine, whatever. I'm finally beginning to hear some parts of transmissions though. The scanner will seem to pick up on a TG, decode the first word or two of a transmission, and then lose it.

I have a good CC lock also.

I guess I'll just keep tinkering with the P25 settings.

Sounds like the multi path distortion is affecting the scanners ability to sort out one transmission. Some people have had luck using a Yagi directional antenna pointed at the strongest tower site. If the signal is strong enough the scanner can not see the weaker signals. Kind of like being blinded by a bright flash light in a lighted room.

I found it helped to move my scanner to different locations in the house. Sometimes it helped to set the scanner on top of a stack of books on a table, sometimes it only made things worse. I fight the multi path distortion when I visit my daughter. Fortunately the closest tower is not part of the simulcast system but I miss traffic if I only listen to that one tower. Not every TG is carried on the tower I receive best.

I hope you get things sorted out. I found it helped me test my programming by driving to different locations to see if the scanner worked properly. If the scanner worked I knew that I was fighting a location issue.

The 700/800 signals are affected by the foilage and your scanner or cell phone will receive a lot better when all the crops are out of the fields and the trees drop their leaves. I find the multi site simulcast system might work better depending on the time of year. You might hear things great and once the season changes the reception changes and signal might get worse.

 

[VASCAR2]

I’m not sure if you clicked onto the Madison County TRS system in the data base here on RR.com but there is a map that gives the locations on all the sites for the north and south systems. Here is a link to the north sites around Richmond.

https://www.radioreference.com/apps/db/?fccCallsign=WQMM789


Here is a link to the map of the southern sites in Madison County.


https://www.radioreference.com/apps/db/?fccCallsign=WQMM788

 

[ofd8001]

I've been to/through Richmond any number of times and have not had much success with receiving this system, unfortunately. Perhaps it could be that I wasn't in the area long enough to give it a fair chance.

Both 996XT and 536 scanners were used.

As a side note, less signal is better on simulcast. I recently had an antenna issue on my truck - cable broke off at base of antenna. I receive our local simulcast system better than I ever did. Didn't receive anything else though (not surprised).

 

[KK4JW]

On a whim, I turned on the 20dB attenuator and dropped the P25 Adjust Level to 25. Yes, 25. Twenty Five, with an P25 Adjust Mode of 8.

Seems I'm getting the best results I've had so far at this configuration. Error rate is mid 40's now.

Still tinkering with settings at this point, but I feel I'm closely fine tuning to the point I may actually be able to hear some transmissions. Maybe I'm *too* close to the transmitter site? Or maybe with the RS800 antenna and the attenuator off, I was receiving several towers, VS just one that's closest to me and that was confusing things?

 

[Charlie1068]

Do you think it is possible to listen to the system with an SDR using Unitrunker, so far I’ve had no success