Programming UHF Trunked system

[jimg]

I am trying to program a UHF system, MANUALLY. The system type is Motorola Type II Smartzone and the system voice is Analog and APCO-25 Common Air Interface. Which trunked system option should I select: Mot VHF/UHF, P25M or P25 Auto? I know the system is analog and not digital. Any help would be appreciated.

 

[fmon]

I am trying to program a UHF system, MANUALLY. The system type is Motorola Type II Smartzone and the system voice is Analog and APCO-25 Common Air Interface. Which trunked system option should I select: Mot VHF/UHF, P25M or P25 Auto? I know the system is analog and not digital. Any help would be appreciated.

Mot VHF/UHF and you must set the trunking table(s)
Lo Ch, Hi Ch, Offset, Base Freq and Step

 

[jimg]

Does "Lo Ch" mean the lowest frequency and the "Hi Ch" the highest, e.g. 406.550 and 409.9500. Also, I have no idea what the "offset" is, as that is blank in the printout. The "Custom Frequency Table" says the base is on 406.000 and the spacing is 25.0. Can you provide further help?

 

[fmon]

Does "Lo Ch" mean the lowest frequency and the "Hi Ch" the highest, e.g. 406.550 and 409.9500. Also, I have no idea what the "offset" is, as that is blank in the printout. The "Custom Frequency Table" says the base is on 406.000 and the spacing is 25.0. Can you provide further help?

What does the table state for offset and is it a single table?

If single table set as follows.
Lo Ch=Offset (likely 380)
Hi Ch=759
Offset=(likely 380)
Base=406.0000
Step=25.0

 

[jimg]

Where would I find the "table" information?

 

[fmon]

Where would I find the "table" information?

On the database page upper left. Custom Frequency table.

What system are you working with? I can't locate Estill Springs.

 

[jimg]

Tennessee>Coffee County>Arnold AFB System, Tullahoma, TN

 

[fmon]

Tennessee>Coffee County>Arnold AFB System, Tullahoma, TN

Don't know why but the offset is unlisted. However, Motorola VHF/UHF channel range starts at channel 380 and ends at channel 759. Thus the first channel is 380 (offset and LoCh) and the last channel is 759 (HiCh).

My post 4 should be your T Tables setting.

We have 4 military bases in southeast VA (1 Air Force, 1 Army and 2 Navy) using the same settings except each have a step size of 12.5.

 

[jimg]

Evidently I'm still not doing something right, as I still hear nothing. In fact, even the squelch does not make any noise when turned all the way down. Would you please review the following settings and advise me if there are changes I need to make or any suggestions? Here is how I have programmed this system:
MOT VHF/UHF
Entered all 5 frequencies shown in database
ID: WILDCARD
AUDIOBOOST: ON
MULTI-SITE: OFF
T TABLES: CUSTOM (i noticed there are 16 tables, but I entered all the information in the first one.)
Trunking Table: Lo 380, Hi 759, Offset 380, Base 406.000, Step 25.000.
Thanks in advance for your help!

 

[fmon]

Your settings are correct and squelch won't be heard on trunking systems, however, the database page doesn't indicate any CC or talkgroup, the site may be inactive. Do any of the 5 frequencies have a control noise?

This was the last entry on history of system: Updated Talkgroups (0 Updated, 9 Deleted) ericcarlson 2008-06-01 20:18:59.

9 deleted talkgroups? Wonder why? Could be a defunct system...a lot of military are shifting to 385 MHz P25 trunking systems. Try doing a limit search starting at 385.0000 to 400.0000. Purpose...to find a control frequency in that range.

 

[jimg]

How should the Fleet Map be set? Is it Fleet Map II? I have nothing in Block 0 1 2 3 4 5 6 7. Should I? Also, should the T Table be set to Custom, Default, or Splintr?

Also, I''m not sure this is good data, because for a long time RR would not post any information about AFB, at their request. Some time ago, I did hear traffic on 407.550.

 

[fmon]

Keep default II and T Table Custom.

RR changed back to publishing military systems.

Do you hear any control noise on any of the 5 frequencies...if not, you are waisting your time until you do.

 

[jimg]

Keep default II and T Table Custom.

RR changed back to publishing military systems.

Do you hear any control noise on any of the 5 frequencies...if not, you are waisting your time until you do.

No, I don't hear anything on any of the five frequencies. I have them programmed in individually in one scan list and then as a trunked system in another scan list, but have not received any signal.

Is there any way to contact RR to see if this info is correct?

 

[fmon]

RR publishes data submitted by users in the area. At top of the Arnold page you will find a 'Submit' button to correct or add data. One of the Admins would then make the change.

Again, the system may have changed from 400 MHz or added new freqs for control. You can run a Limit Search on 385 MHz as previously suggested but include a second search for 406.0000 to 410.0000.

 

[mikey60]

Try doing a limit search starting at 385.0000 to 400.0000. Purpose...to find a control frequency in that range.

I'm going to suggest a change in the search range here. Most of the military trunked systems are running with the repeater outputs in the 380.0000 - 390.0000 Mhz range (Mobiles are in the 390-400Mhz range). Search in that range for a control channel.

Mike

 

[fmon]

I'm going to suggest a change in the search range here. Most of the military trunked systems are running with the repeater outputs in the 380.0000 - 390.0000 Mhz range (Mobiles are in the 390-400Mhz range). Search in that range for a control channel.

Mike

Thanks for helping out Mike, I noticed a few birdies in 385-390 also.

BTW, searching in range 406 to 410, I get voice traffic with P25: 1A5 and P25: 1C6 on bottom left. I know the systems for each but what does the 3 characters after P25 indicate?

Thanks again for outstanding support.

Edit: Ah, found them stored in Conv Objects. NAC

 

[jimg]

Thanks everyone for your help! I will try searching as you suggested and let you know if I find anything.

 

[jimg]

Thanks everyone for your help! I will try searching as you suggested and let you know if I find anything.

Here are the active frequencies that I found during my search that appear to be part of they system I am trying to monitor: 387.4625, 387.8125, 389.3125. I have heard traffic on these and it sounds like part of a trunked system, however, I have been unable to identify the "control channel" or any ID's and I'm not positive these are all the frequencies that may make up this system. Where do I go from here?

 

[LEH]

I'd set the scanner on search and wait for the motorboat. You have the general band, just let the scanner go for awhile. If it is trunked, which it most likely is, the CC will have to show up eventually.

You're getting closer, as you have discovered, it takes some time and perseverance. One of the joys(?) of scanning.

Once you have found the control channels, don't forget to click the submit button above the system so you can report them and have the DB updated.

 

[jimg]

RR publishes data submitted by users in the area. At top of the Arnold page you will find a 'Submit' button to correct or add data. One of the Admins would then make the change.

Again, the system may have changed from 400 MHz or added new freqs for control. You can run a Limit Search on 385 MHz as previously suggested but include a second search for 406.0000 to 410.0000.

The RR database was updated this week to show that this system, U. S. D. O. D., Arnold AFB, Tullahoma, Coffee Co., TN is now a digital Project 25 Standard. The RR database list two control channels, 385.71250 and 385.96250. Additionally, I regularly monitor traffic on these frequencies: 387.4625, 387.8125, 389.0375, abd 389.3125. However, I have been unable to set this up in my scanner as a TRUNKED SYSTEM, and have only been able to receive in the "CONVENTIONAL" mode. I would like to be able to program this system so I could receive it as a trunked system, but I need some HELP! Can you advise should my scanner, GRE 500, be set to MOT VHF/UHF, P25 MANUAL, or P25 AUTO? Should I enter the control channels only, or all of the frequencies I mentioned? Do trunking tables need to be entered, or should it be set to default? If trunking tables are needed, where can I get these? Also, do trunk group numbers be added or can I use the "wildcard" instead? Any help would be greatly appreciated!