Mxsmanic wrote:
The irrational prohibitions are those against devices that are not
transmitters, such as laptops, GPS receivers, and the like. But most
air crews haven't a clue in this domain so they ride on superstition;
some airlines do the same.

Not irrational at all. Just because something isn't called a
transmitter, doesn't mean it isn't one. Laptops, GPS receivers, many
radios, are all inadvertent transmitters. Laptops because of their
onboard computer clocks at maniacal rates. Many types of tuners also
produce interference frequencies.

One of the most popular projects in 60s electronics magazines was for
non-transmitting (passive tuning) airline receivers you could use on a
plane.

Kev