[aprssig] Re: aprssig Digest, Vol 21, Issue 8

[KC2MMi]

Bob-
 Perhaps your cell failure was a result of the old FM capture problem? i.e.,
everyone can see the tower, but only the hundred (whatever) strongest incoming
signals will capture the free channels on the tower and get connections. I've
seen similar problems, where all it took was putting an external antenna on the
cell phone and SHAZAAM! it got and kept a connection that a plain handheld could
not. If there was a town or highway closer to the tower...and you were in the
nosebleed seats, so to speak, that's enough to shut you out.

It should be cheap enough to buy a magmount for your cell (there are yagis as
well for higher gain, not terribly expensive<G>) and convert it to a dipole or
j-pole. (Cheaper to buy the whole antenna in order to get the special plug to
fit the phone.) Roll-up pocket colinear cell phone array?<G>

 If the towers were more than 3 miles away from you, I doubt they could hold a
call from your phone, no matter how well you could hear them. I say three miles
because I've held a tower with "two bars" that far offshore, but that seems to
be a limit for the stubby antenna in most handheld phones.


Andre-
 <<The GSM system like it used in europe is better matched, it also alows
the tower to controll the mobile´s output power (most of the time the
handheld will be in the 10mW range)>>
 Some or all of the US systems do that as well. Even the TDMA phones are smart
enough to go to full power whenever 911 is dialed, at least on my carrier. I
suspect the power control logic was something that each carrier could specify as
a custom program option since it seems to vary by carrier, if you can get them
to talk about it at all.