hi, the above tx. has been bound to the 120sr and flown before. now when i decide to fly, i turn on the tx., plug in the battery the red light begins to flash rapidly.

it will do this for a couple of tries and then on the 3rd or 4th try, the red light stays on solid and i can proceed to fly. any ideas why this can happen if the 120 was already bound to the dx5e? it never did this when i was using the stock e-flight tx.

thanks!

This happened to me when I tried to bind with the heli sitting on the (metal) tailgate of a truck. Both TX and RX need to be at least 3 feet from a solid metal surface, and farther than 3 feet apart. Has to do with radio wave saturation and reflection which are particularly critical during binding.

You should wait 5 seconds after turning on the radio before plugging in the heli so the radio can acquire the channel that is clear of noise

thanks for reply guys but clear something up for me. when you first bind a transmitter to a heli, then it should be bound for good unless changed. but the light would flash like it was trying to bind all over again. this all happened in my living room no where near metal objects and tx and rx were about 5ft apart. i waited at least 5-10 secs. before plugging in battery. is interference the only reason why this can happen?

The light flashing means the RX is trying to acquire the channel pair the TX chose AND the model code it "bound" to. The process is more complicated than it looks. Mostly it works but when it doesn't it can be hard to define exactly which process failed.