Hi guys I have mini video rx tx 32 channel and a linearly polarised antenna with it. Now I upgrade them to circular polarised by using diy thread. They works well.but problem is just started when tx and Rx is inserted with cp antenna. The tx and Rx getting more hot than stock antenna.

As this is a DIY:

if there is a 10 ~15% deviation in the dimension of the antenna from the design requirement, the impedance of the antenna changes for that frequency band and causes your TX to heat (impedance mismatch causes more signals to bounce right back into to the TX ,from the antenna, causing heating).

From what you described, it looks like you're having a case of high reflection from the antenna.

I would recommend you to remake the TX antenna (3 lobe one) with better size and shape tolerance.   

Hi sid thanks for reply. As you recommended will remake tx antenna again but what about rx it is also getting warm....

Rx getting warm is a bit strange (as its not gonna be transmitting any power).

What Rx are you using ?

This one from bang good.com

a heating up receiver is unheard of by me. Is it heating up too much? or just getting warm
a bad antenna on Rx shouldn't cause it to heat up, only loss in video reception should happen.

Its getting warm.....

warm is fine and normal.
HOT to the touch means something is wrong.

Ok thanks a lot