Low pass filter is a great device to add to your FPV system, it protects GPS and 2.4 GHz radio signal
Video transmitters can cause interences on some onbord devices such as R/C receivers...
900 MHz transmitters can have their harmonics aftecting the 1.5 GHz band used by OSD GPS or even 2.4 GHz radio system.
Low pass filter can help with interferences or harmonics by filtering them.
It provides a very good filtering at 1.5 GHz (GPS band) and and excellent 2.4 GHz.
Low insertion loss
Insertion loss 0.5dB at 910MHz
Insertion loss 25dB at 1500MHz
Insertion loss> 43dB at 2.4GHz
50 Ohm impedance
10W Max Power
-55C to 100C Operating Temperature Range
Most installers are aware that maximizing the distance between the A/V transmitter and the RC receiver is important. But for some reason they ignore such words of wisdom, perhaps because they have a compact installation that makes this difficult to do.
Another way to reduce radiated noise from your transmitter case and wires, is to run your power and video cables multiple times around a toroidal ferrite rings as close as possible to the transmitter.