Has Anybody Here Used One Frequency Trunk On Uniden On Federal Monitoring?

[JASII]

One of things I like to do from time to time is simply search the federal bands for activity. The alternative is to scan a group of sequential frequencies that is, in effect, the same as searching. One of the downsides of this is you can often hear interference from intermodulation, mixing, front end overload, etc. I have always wanted the ability to scan or search APCO P25 only, but I don't believe that is currently possibly with the Uniden scanners.

So, yesterday, on a different thread, I was reading about using the One Frequency Trunk method to monitor DMR and not hear the "rest channel" activity on CAP+ frequencies. Has anybody here tried doing that with federal frequencies? Would it work?

 

[ecps92]

Yes, but mainly for "RID" identification and even that can be tricky unless you label the channel correctly.

When I reference label correctly, if you have a freq that is used by different agencies/NAC's ensure you program the NAC with the label
otherwise you may tend to make notes/reference to the wrong agency/users.

One of things I like to do from time to time is simply search the federal bands for activity. The alternative is to scan a group of sequential frequencies that is, in effect, the same as searching. One of the downsides of this is you can often hear interference from intermodulation, mixing, front end overload, etc. I have always wanted the ability to scan or search APCO P25 only, but I don't believe that is currently possibly with the Uniden scanners.

So, yesterday, on a different thread, I was reading about using the One Frequency Trunk method to monitor DMR and not hear the "rest channel" activity on CAP+ frequencies. Has anybody here tried doing that with federal frequencies? Would it work?

 

[JASII]

Yes, but mainly for "RID" identification and even that can be tricky unless you label the channel correctly.

When I reference label correctly, if you have a freq that is used by different agencies/NAC's ensure you program the NAC with the label
otherwise you may tend to make notes/reference to the wrong agency/users.

Thank you for the reply. Yes, that is a great point. So, if I understand this correctly, there would be NO analog signals coming through the speaker and, hopefully, no intermodulation, mixing, front end overload garbage, but ALL APCO P-25, in the clear, regardless of NAC Code would come through?

The other thing I am trying to determine is how many of these One Frequency Trunk Systems I could fit in a site/system/group. For example, could I program the entire 162-174 MHz area in 12.5 kHz steps. Probably a monumental task, however!

 

[ecps92]

Been awhile since I did this, but Yes, if set as P25 then no analog and if No NAC, they you hear all, but have no idea which NAC is being heard.

example - right in my area on a normal basis I had/have 163.7000 with $169, $200 and $301 - now down to $169 but what a PITA in the past.

I've seen folks program the entire Federal in "auto" and/or various modes without running out of memory, but never seen anyone attempt the entire VHF/UHF in Single Freq Trunk, not sure how much more memory that takes.. We've only done it on a handfull of local channels

Thank you for the reply. Yes, that is a great point. So, if I understand this correctly, there would be NO analog signals coming through the speaker and, hopefully, no intermodulation, mixing, front end overload garbage, but ALL APCO P-25, in the clear, regardless of NAC Code would come through?

The other thing I am trying to determine is how many of these One Frequency Trunk Systems I could fit in a site/system/group. For example, could I program the entire 162-174 MHz area in 12.5 kHz steps. Probably a monumental task, however!

 

[JASII]

...but never seen anyone attempt the entire VHF/UHF in Single Freq Trunk, not sure how much more memory that takes...

I was experimenting with this last night on 450/460 MHz frequencies. Using Butel ARC536Pro, it offered 256 frequencies. It did allow me to enter more than that on the software, but when I did "Write" to radio, it did not save them. When I reduced the number to less than 256 and wrote them to the SDS100, all of them were saved.

With regards to the federal bands and using 12.5 kHz steps, each one mHz will be 80 channels. Thus, 256 frequencies is just a bit over 3 mHz of spectrum using 12.5 kHz steps.

Federal VHF/UHF Channel Plans - The RadioReference Wiki

wiki.radioreference.com