Atis

[BMT]

All military ATIS only run 10 Watts.

BMT

 

[majoco]

Fascinating. Why would they need to run anything higher?

There's no need for ATIS to cover the globe, it's a "terminal information service" so if you were in an aircraft you would possibly only need to listen to it just before switching from radar to tower control, probably no more than 25miles out - so 10 watts is perfectly adequate.

Cheers - Martin ZL2MC

 

[WA1ATA]

All military ATIS only run 10 Watts.

Are you sure about that?

What sort of antenna do they use?

I receive a weak, but readable ATIS signal from Travis AFB on 135.55MHz on a Uniden BC95XLT with an indoor twinlead J-pole (cut for 124MHz) taped to the wall next to my computer.

Per Google Maps, Travis is 72 miles away from my houses the crow flies. And that crow would have to fly over the East Bay hills, which blocks
my line of sight to Travis.

If find the Atis stations very useful for checking the sensitivity of radios and the performance of airband antennas, in the same way that NOAA weather stations are useful for checking out marine/railroad antennas. VOR's and Atis were particularly useful for tuning my airband J-pole in that there are weak stations in both ends of the band.

 

[majoco]

You're assuming that the antenna is on the base. Often the ATIS transmitter and antenna are off-base at a high elevation comm station such as the radar control transmitter site.

Cheers - Martin ZL2MC

 

[CalebATC]

So I am guessing you found this in some website/military requirements manual etc, or talked to someone at Homestead

Great find, I have always wondered.

Is this for both VHF and UHF? It always seems like they come in the same, but sometimes they are really different.

I'm sure a various amounts of airports run different power with their AWOS, ASOS and ATIS stations, especially with airports that run a ATIS for departing and arriving. The FCC ULS says the local airport here runs 1.5 watts on there ATIS.

 

[BMT]

Every military ATIS I checked run's 10 watts.

BMT

 

[CalebATC]

Where did you find this at? ULS?

 

[majoco]

I'm trying to see the point of this observation, but so far it has eluded me.....

 

[greedo23]

Pilots are supposed to listen to the ATIS before making their first contact with any controller at the airport they are intending to fly to. (At an airport with class B or C airspace this would be the approach controller) This first call to the controller usually takes place somewhere between 10 to 20 nautical miles from the destination airport. 10W would be adequate to cover this distance. Military bases are a different entity. Someone from the military would have to comment on how powerful the ATIS is on bases.