NPS GSMNP Analog

[kf4lhp]

Monitoring traffic on 169.550 NPS GSMNP repeater; UT LIFESTAR enroute on a motorcycle wreck. They are using analog on 169.550 with PL 123.0 to talk to NPS units on the ground at the LZ. Apparently LIFESTAR doesn't have P25 capabilities.

 

[tennesseefreq]

I have noticed that all the park channels that I have monitored use the 123.0 tone in analog.

 

[n4yek]

This will blow your mind, I have actually monitored a park service personnel talk in analog and the dispatcher (aka 700) respond in digital. Both carried on the conversation like it was nothing,
I wonder if the one radio was having problems of some sort transmitting digital but could receive digital?
I have noticed this on more than one occasion so it wasn't a one time thing.
I would love just to be able to see how their communications are laid out through out the park.

 

[Gatorman]

Analog V Digital

Typically the systems are set up so they hear both modes. That way they can use the older plus the new technology simultaneously. Plus, if a particular radio is unable to operate in P25 mode, it can still work as an analog unit.

The encryption modes work the same way. The base station will hear an encrypted as well as an unencrypted signal. Thus, if a radio drops the code, which is frequent, he can still talk to someone.

 

[wwhitby]

When I was up in Gatlinburg last July, I heard the Park Rangers using analog modulation instead of digital, since the range was too great to contact each other using digital.

I ended up programming each frequency in my PSR-500 twice - once to search for a NAC and another to search for a PL tone.

Warren

 

[rjones]

This will blow your mind, I have actually monitored a park service personnel talk in analog and the dispatcher (aka 700) respond in digital. Both carried on the conversation like it was nothing,
I wonder if the one radio was having problems of some sort transmitting digital but could receive digital?
I have noticed this on more than one occasion so it wasn't a one time thing.
I would love just to be able to see how their communications are laid out through out the park.

They have recently added some more repeaters to their system, so maybe that will improve things. I know I did receive them a lot better along River Road this fall then I have in the past. From time to time you may hear the Rangers telling "700" that a repeater at such-and-such site is having problems, but I'm always driving when I hear that so haven't been able to write down what they are. Guess I need to get a Y cable so I can tape while I'm driving.

Here is what I have loaded for GSMNP

P25
166.35
167.15
169.55
170.3375
170.3875
170.875
171.1625
172.525
171.0625

I have also logged them on 139.4625, 141.2625, and 143.2625 in P25 mode. Don't know if this is linked for the Tn ANG or ArNG, or maybe just and image.

I have not heard any activity on the UHF links, so I wonder if they got cut out when the digital upgrade took place.

 

[ccfire]

I can hear them talking on 172.525 where I live it comes in as good as twra on waucheesi

 

[kf4lhp]

Here is what I have loaded for GSMNP

P25
166.35
167.15
169.55
170.3375
170.3875
170.875
171.1625
172.525
171.0625

I hear them rock-solid in Harrison, just north of Chattanooga, on 169.550. Get a good signal on 172.525 as well, and an intermittent signal on 171.1625.

 

[n4yek]

So I don't hi-jack this posting I started a new one:
http://www.radioreference.com/forums/showthread.php?p=909339#post909339