[ltp] Re: Linux-Thinkpad digest, Vol 1 #632 - 27 msgs

[Don Perley]

>
>
>>
>> Does this make sense to all you experts out there?  Am I finally off the
>> hook for my tragic "amps" error?
>

Sort of.. we now know that it was a limited scope study, with limited 
scope conclusions.

Just an example of  unexpected things that can cause interference when 
you get beyond simple tests..  There is a interference situation on a 
local mountain top where the best guess is that the signal from an FM 
radio station and that from a weather radio transmitter are combining in 
a parasitic diode mixer formed by rusty bolts on a tower and spitting 
out interference on a 3rd frequency nowhere near the other 2 (but 
related by a common intermodulation relationship).

The moral of the story is that when  you get a cabin full of passengers 
with gadgets spitting out various frequencies even at micro or milliwatt 
levels, you can get results matching those used by the avionics front 
end, intermediate frequency, local oscillator, etc.  Antenna cables and 
other wires  go all over the plane  giving a  path to the cockpit.

If the end result is a problem with the avionics, it is not going to be 
a time critical emergency if the plane is on a stable flight path.  On 
take off or landing you don't have time to deal with it; hence the 
typical announcement to keep your toys off until the plane gets to 
10,000 feet.