FPV question

[Pontius]

I'm just starting out with a DIY build - I'm hoping to get as much fun from designing & building as from flying. I haven't decided on the 'copter size & parts yet (no doubt I'll ask questions about that in this forum soon), but I decided to start with the bits that are more generic. So far I have purchased a LiPo charger, a 6 channel 2.4GHz R/C Tx and Rx, and some 5.8GHz FPV bits (a TS353 400mW transmitter, receiver, camera, pan& tilt camera mount and LCD screen) because I definitely want FPV. My DIY so far has been to make a bracket to mount the screen and FPV receiver to the Tx unit and fit rechargeable LiFe batteries to the R/C Tx that will power it and the FPV receiver & screen for plenty of time between charges (I used LiFe because the voltage is more compatible and at £10 for 5000mA at 12V its cheaper than LiPo where weight is unimportant). When testing the setup, I found that the R/C signal affects and is affected by the FPV signal - it is usable but with reduced range for both R/C and FPV compared to when they are used separately. I can separate the FPV receiver aerial from the R/C transmitter which improves the FPV range (though not so convenient), but obviously the FPV Tx aerial has to be close to the R/C receiver. Is this interference usual? Is there any way to eliminate the cross interference? My R/C kit is pretty cheap (Fly Sky CT6), so maybe I need a better Tx/Rx setup? I thought of maybe mounting the FPV transmit aerial above the R/C aerial with some foil between to screen some of the interference.

 

[Hugh Hemington]

First, I assume you're using circularly polarized antennas? The "stick" antennas generally provided with this gear are "sub-optimal". Second, if you use a circularly polarized antenna on the 5.8, it'll be pretty small, and you may be able to put it on the BOTTOM of the quad, leaving the RX antenna on top. Don't be afraid to adapt longer legs if needed, but if you've already got gimbals under there, you should be able to mount an antenna behind that.