Question Reguarding Scanner Freq

[MaddChatter2608]

I was wondering.....My local FD just switched to a NFM band rather than the conventional FM....i have the new frequency and it works fine. However, i cannot pick up their Tones only their Speech!!! I have inputted the DPL the database has listed but next to the Frequency Description it has another code (Input D454). Should i input the D454 as the DPL or is that for the input frequency only???? Any help would be appreciated!

 

[bezking]

Don't program anything for the PL/DPL and see if it works - I doubt they are laying the tones on top of the DPL; that would cause the pagers to not decode the tones properly.

 

[MaddChatter2608]

Thanks!!! That was kind of the direction that i was heading....but i was afraid it wouldn't work right without the DPL!

 

[GTR8000]

I was wondering.....My local FD just switched to a NFM band rather than the conventional FM....i have the new frequency and it works fine. However, i cannot pick up their Tones only their Speech!!! I have inputted the DPL the database has listed but next to the Frequency Description it has another code (Input D454). Should i input the D454 as the DPL or is that for the input frequency only???? Any help would be appreciated!

The input is irrelevant. "D454" is the DPL of 454, the "D" only indicates that it's a DPL not a PL. As bezking said, try removing the DPL altogether and see if you hear the tones. There are times where agencies will send the tones CSQ followed by the voice message with PL/DPL enabled. I suspect we'll see this more frequently with narrowbanding because agencies are using older pagers that aren't narrowband compliant. Sending the tones without PL/DPL minimizes any distortion so they come through "cleaner".

I do disagree with bezking on the point of tones not decoding properly when sent with PL/DPL. That's simply not true, thousands of agencies send tones with PL/DPL enabled and they work just fine. It's only the recent move to narrowbanding and the usage of non-narrowband equipment that might cause some issues.

 

[bezking]

Thanks for the correction, 6.

Don't worry about the DPL. The only thing it does is cause your receiver to open on transmissions that send the DPL. So, if someone on that channel transmits without that DPL, you won't hear it. This is useful for keeping others who may be on the freq from opening the radio.

If you don't program a DPL, your radio will open for EVERY communication on that freq, so you will hear everything.

 

[GTR8000]

Yeah I agree, it's usually not a big deal unless you happen to have nearby users on the same frequency that you don't want to listen to. If that's the case AND the dispatch center is sending the tones without the DPL, then you'll have a decision to make: program the DPL so you don't hear the other users, but won't hear the tones either...or leave the DPL off and hear everything that comes over the frequency.

 

[MaddChatter2608]

Thanks for all the advice....took the DPL off completely....they are the first in our area to switch to narrowband so i'm not too worried about others on their new frequency just yet.....will wait and see what happens.

 

[MaddChatter2608]

Glad to say that I received their tones this morning on a call....so obviously taking the DPL out was a good idea!