Cellphone Use in the Air

[Piloto]

Denver Pilot

Thanks for the detail antenna explanation. But the most important reason for the cells to use co-lineal antennas is to maximize cell sensitivity when receiving a 1/2 watt signal from the cell phone. Mutual signal overlapping is usually controlled by the cell transmitted power. If the co-lineal antennas would have such highly directional pattern to the ground you would be able to receive in the air only the ones in the horizon but not the ones below. But the reality is that in the air you receive the one below and the one in the horizon thus creating mutual interference. BTW ATC coastal VHF stations for Oceanic communications use co-lineal and yagi antennas to maximize range.

José

 

[denverpilot]

Denver Pilot

Thanks for the detail antenna explanation. But the most important reason for the cells to use co-lineal antennas is to maximize cell sensitivity when receiving a 1/2 watt signal from the cell phone. Mutual signal overlapping is usually controlled by the cell transmitted power. If the co-lineal antennas would have such highly directional pattern to the ground you would be able to receive in the air only the ones in the horizon but not the ones below. But the reality is that in the air you receive the one below and the one in the horizon thus creating mutual interference. BTW ATC coastal VHF stations for Oceanic communications use co-lineal and yagi antennas to maximize range.

José

Yup yup. It's a two way street, transmit and receive. Antenna gain and pattern helps both directions.

This is why my mantra for newbie radio folks is "the antenna makes the radio". People buy amplifiers and blah blah blah, and then transmit into a wet noodle.

We could get into how many people I've wanted to strangle personally for using fiberglass collinear antennas on multiple transmitter sites instead of DC-grounded folded dipole arrays, who created un-Holy amounts of passive intermod with a cracked joint in the interior of the antenna...

Whaling on it with a non-conductive wooden broom handle while the mixing transmitters are up and you're listening to to poor affected receiver works great to find it, and has the added benefit of taking out that murderous stress while hanging from the tower on a cold day... and if you're lucky their POS antenna will fall off the tower. Haha. Kidding on that last part.

I'm a Sinclair fanboy. Sinclair HD folded dipole arrays last forever and work. Fiberglass sticks are usually scooped up in a small trash can after the lightning strikes.

The folks paying the radio system bills that I play with right now are Decibel Products fans. They're fine, but don't outlast a Sinclair.

 

[Alexb2000]

I get coverage over most metro areas up to about 10K w/ AT&T. I don't make calls on my phone, but I do text. It is so much easier to text a quick message to someone waiting on the ground vs. having them sit around for 30 minutes because your passengers were late AGAIN. Also, a great way to comfort the wife when you are running very late.

 

[denverpilot]

Data coverage is somewhat simpler in that the texts are store-and-forward.

Fire up Speedtest.net at 10K above a city and it'll usually completely fall apart and drop out of data mode. The indicators on the phones basically lie and say life is grand until data is truly sent and fails.

Voice is worse. The other day I found a very cool spot in a datacenter where my VZ phone would show "three bars". ID place a call, it would connect and drop in ten seconds. Phone would show no service. It's then check in again, "three bars" once again.

I repeated this four times just to play with it. Phones are just basically coded to lie about "bars".

 

[LDJones]

I am right with ya ol buddy..... I have NEVER texted any one... A phone call is so much easier..

Benefit is you can convey information without disrupting their current activity and vice versa. I love txting and use it all the time. For my flight students, most if whom are 20-something's, it's their preferred method of communication since they can communicate in places/situations that a voice call is not possible.

I'd never know what my college kid was up to if I didn't use txting!

 

[TheTraveler]

Benefit is you can convey information without disrupting their current activity and vice versa. I love txting and use it all the time. For my flight students, most if whom are 20-something's, it's their preferred method of communication since they can communicate in places/situations that a voice call is not possible.

I'd never know what my college kid was up to if I didn't use txting!

Agreed! I was skeptical of texting at first, but I soon came around like so many others. I won't do it while I'm driving, but it's extremely useful for all the reasons and in all the situations you mentioned.

After a while I actually started chatting with some friends through text, and it works kind of like a thread. Between a few friends we send short texts a few times a day, but there isn't any rush to respond. It breaks up the day nicely. Unless of course you have an iPhone and are cursed by the ever frightening Auto Correct...

http://www.buzzfeed.com/daves4/the-25-funniest-autocorrects-of-2012

(Warning: Please click this link with caution! It may contain some offensive or grown-up material, and is not for everyone. If inappropriate for the group, I apologize in advance, and I will gladly remove it upon request.)

 

[airguy]

Out here in west Texas where I do most of my flying, voice coverage is next to useless above about 5k', but text messaging continues to function quite well, I would say 70% to 80% coverage with 5-10 minute dropouts. Definitely sufficient to hold conversation with ground folks to update times or get weather info etc.

Couple weeks ago I could not get enough data to pull the radar pic on my cellphone - my wife did it at home, snapped a screenshot of it, and texted that screenshot to me. That route took a LOT less bandwidth than me accessing the site directly.