I have been using RHCP antenna on my quad.

But I need an extra antenna this weekend, I can get it from a local shop, but they are all out of stock with RHCP antennas, only have LHCP in stock.

So can I mix RHCP with LHCP? or Do should I replace both my VTX / VRX antenna with LHCP antennas?

Probably not a good idea, you will still get some signal but it won't be great.

Between the two types, the signal on LHCP and RHCP kind of rejects each other, it's used to reduce multipathing, and reduce the bleed over between close VTX channels.
I think you should stick to RHCP, it's not really worth it unless it's your second or third set and you're a very social flyer

no they have to be the same, you also cant use a linear polarized stock antenna with a circularly polarized antenna

I would go with RHCP because that tends to be more common, If you want to get a nice helical for diversity later on you wont have to worry as much about finding one that's LHCP, they seem to be less common.

(10-Feb-2016, 08:40 PM)CurryCat Wrote: I would go with RHCP because that tends to be more common, If you want to get a nice helical for diversity later on you wont have to worry as much about finding one that's LHCP, they seem to be less common.

And that is exactly the point why i went LHCP
I'm afraid that some douchebag just starts up his quad near me and doesn't check his channel first. And because 90% (edjucated guess) is flying RHCP i went for LHCP.

For Antennas i get only quality ones and nowadays you can find everything in LHCP.

I am using RHCP for receiver and LHCP for transmitter. Havent noticed any problems with signal. Probably because i dont fly far away. But ive ordered some RHCP tx and rx antennas today.

(11-Feb-2016, 09:55 PM)Gotvaldas Ambrazaitis Wrote: I am using RHCP for receiver and LHCP for transmitter. Havent noticed any problems with signal. Probably because i dont fly far away. But ive ordered some RHCP tx and rx antennas today.

If you mix them you get about -13dB attenuation !!! 3dB is about half the range.