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FPV general trouble shooting guide
Read this first and try some of this before asking around.
Any FPV system car or plane or helicopter or whatever is often a compact system, containing:
transmitters, receivers, sensors, hi power pulsed electrical, vibrations, microcontroller electronic boards,
video camera, switch mode supply too be able to combine all this into a tiny lightweight platform is a huge
challenge and to make all units perform perfectly without interfering each other is often an almost
impossible task, even for skilled electronic educated persons.
Design hints:
Plane size
small planes are cheap and easy to transport, but they are not optimal FPV platforms. The
smaller type the more compromised performance you must expect to get.
Receivers
must be located as far away from transmitters as possible, at least a distance that can prove no
degrade of the receiver system range when the Tx is operating or not.
It is advised to keep receivers away from all electronics, in general, speed controllers and switch mode
supplies are known to be able to jam.
Electric Motor controller
a range check must prove no degrade/change when motor is off, halve, full
power, this also apply for gasoline and methanol engines
Transmitters
for live video or data back telemetry will always have harmonics, like 2x 3x and so on of their
wanted frequency the level might be low and under demanded levels, but when located near a receiver
that may operate on a x2 or x 3 frequency it is doomed to fail! Plan your frequency bands to avoid using
any channel at the exact harmonic of any other system you use.
GPS
are often small module receivers, designed to be cheap and just cheap!! That is what we like, but
cheap come with a problem price. They are not designed to be working near transmitters; some cannot
handle anything not even if it is even GHZ away!! so a SAW front end is a must and a good high level
capable front end is a must too, and even then some GPS modules do not like to be located near 900 or
1300MHz video transmitters first harmonic of 900MHz is 1800Mhz, a GPS works at 1575MHz its front end
