Base frequency help.

[bigray246]

My home town went to a Motorola UHF P25 digital trunked system. Just bought a Uniden 796D how do you find out what a UHF trunked systems base freq., offset, & channel #s are? Is there a formula, or a way to obtain this info, the scanner will not work without it. HELP.

 

[rescue161]

If the system is not in the database on this site, then you'll have to run a program like UniTrunker or T4Win to find some data. Once you have a few pieces of data from those programs, you can use a formula to figure out the rest. You'll be able to get the base, offset and frequencies using the formula in this Word document. Wayne_H made those instructions. He also made a spreadsheet that helps as well. I think using the instructions is easier to understand.

 

[bigray246]

Unitrunker

OK I downloaded the Unitracker program, installed the info, connected my PSR500 but no matter what COM port I select it will not read the the scanner, just says NO SIGNAL. Has anyone tried this program with the GRE scanner?

 

[SkipSanders]

Unitracker does not connect to your scanner via the COM ports. Did you read the instructions?

Unitracker needs discriminator-tap AUDIO from the scanner, fed to your computer's sound card, or a data-slicer connected to that same discriminator-tap audio and to your computer via COM port.

You can TRY using earphone jack audio, but it's not likely to work... You could get lucky, though.

 

[loumaag]

I assume you mean this system.

If the firmware in your 796D is up to date, you don't have to set anything for a VHF or UHF Project 25 TRS. You can just use the defaults that go for the analog type Motorola systems; the radio will ignore them in any case (it gets the band plan from the CCh data stream). You do have to supply the radio with all of the frequencies used. If the firmware is not up to date, a trip to the Uniden site (product support) will supply you with the necessary stuff to update the radio.

You do not have to use any decoding software (UniTrunker, etc.) to figure it out.

 

[mtindor]

Unitracker does not connect to your scanner via the COM ports. Did you read the instructions?

Unitracker needs discriminator-tap AUDIO from the scanner, fed to your computer's sound card, or a data-slicer connected to that same discriminator-tap audio and to your computer via COM port.

You can TRY using earphone jack audio, but it's not likely to work... You could get lucky, though.

The latest Unitrunker works on a PSR-500 by connecting to a USB comport using the cable provided with the PSR-500. The PSR-500 does not require a discriminator tap for its output to be collected by Unitrunker - the PSR-500 has a PC-IF port which spits out computer data (already translated internally) that Unitrunker recognizes and displays info from.

Mike

 

[mtindor]

OK I downloaded the Unitracker program, installed the info, connected my PSR500 but no matter what COM port I select it will not read the the scanner, just says NO SIGNAL. Has anyone tried this program with the GRE scanner?

Yes, the latest version of Unitrunker works fine with a PSR-500. Verify by some other method that you have the PC-IF cable properly installed/detected, with drivers installed, and that it is functioning for other programs.

Hit PGM, then select FUNC, then select GLOB
- Find the CCDUMP option and set it to ON
- Save

That will allow the PSR-500 to send the control channel dump data out the PC-IF port

Then open Unitrunker. Go to the [R]eceiver menu and make sure you select Null Input for the Audio Input and set the appropriate Com Port that the PSR is hooked into.

Once you have Unitrunker working with the PSR, sit on an active control channel for a while and watch for the 3 digit (3 character) channel numbers. You'll need that information to help determine the proper base/offset.

Mike

 

[SkipSanders]

Ah, Ok. I didn't see that function mentioned in my copy of the PSR-500 manual. Tricky.

 

[loumaag]

Mike & Skip,

Can we stay on topic here? The OP does not have a PSR500, he has a BC796D. Nothing that you are discussing about the PSR500 will help him. In any case, he doesn't need the information (as I pointed out in my previous post) provided by UniTrunker.

 

[n2mdk]

Mike & Skip,

Can we stay on topic here? The OP does not have a PSR500, he has a BC796D. Nothing that you are discussing about the PSR500 will help him. In any case, he doesn't need the information (as I pointed out in my previous post) provided by UniTrunker.

See the 3rd post in the thread it's from the OP. I just have to interject, it's in my nature.

 

[loumaag]

See the 3rd post in the thread it's from the OP. I just have to interject, it's in my nature.

Yeah, guess I missed that; but the OP is about his 796D. <embarrassed icon no longer available>

The 500, references to UniTracker, and all of that is just snow obscuring the fact that his 796D (with the current firmware) is ready to go right now.

 

[bigray246]

Bc796d

Thank you all for your help, I downloaded the latest firmware from Uniden and the scanner now works great without the need for any base freq.s! What a relief.