Bear is correct.
Before we went digital in York County, PA, we used Motorola and Plectron monitors. The Dual paging tones are not the same as DTMF, which is Dual Tone Multi Frequency (used on telephones).
Unfortunately, the UV5R doesn't have that capability.

John K3NXU 
Http://www.miklor.com 

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On May 26, 2013, at 1:34 PM, Bear Albrecht <ebear422@gmail.com> wrote:

On 5/26/13 11:10 AM, Brad NK8J wrote:
Most Fire Stations and ambulances require DTMF Tones to tell them which
station is being sent out to where.  
Well, not exactly.  The system here is "two-tone" which has one single tone transmitted for a couple of seconds and then another single tone for a couple of seconds.  Precise timing I can look up on Tuesday if needed.  Google "two tone paging" for some of the angles.  http://www.batlabs.com/qcii.html has some of the info although it doesn't cover what we use, nor several other variants.

One of the tone plans out there is called "Plectron"; it's used in the next county to the north.  In this county we use the Motorola tone plan.  Here's a sample:  The first column is Motorola's "hex code" (why they call it that I don't know but that's what we put into the dispatch console to specify the tone pairs), and the other are the two tones sent in sequence.  (Missing initial columns are the various people's names and call signs.)  One annoying thing about Motorola's approach is that they include frequencies below 300 Hz and I have removed them whenever possible.  Icom and Kenwood radios can be set up to double as pagers but they don't work well with 296.5 and basically don't work with 288.5

3800 553.9 1092.4
3855 726.8 953.7
3801 903.2 1063.2
3898 903.2 1034.7
3803 553.9 304.7
3804 553.9 313.0
3808 533.9 1034.7
3818 584.8 1034.7
3807 553.9 1006.9
3815 584.8 953.7

DTMF is another whole thing.  It's one of many possibilities for ARES paging that we need to figure out.

HTH
;B
-- 
Bear Albrecht  W5VZB
San Antonio, New Mexico
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