L8cruiser

I just moved up to a 2.4 radio. Does it matter if the 2.4 short receiver antenna is outside the plane. Can it be wrapped up completely or needs to be visible. I am used to the 3 foot 72 MHz antenna hanging out of the plane. Also is a double 2.4 antenna really necessary ? Thanks , btw I am donating all my 72 MHz radio to someone just getting started in the hobby. Someone on this forum was kind enough to donate it to me when I was getting started. It is worth more to me to help somebody than get a few bucks for it.

Top_Gunn

My Feedback: (6)

Inside the plane. I've never seen one mounted outside. And yes, you need both of them. Mount them the way the directions tell you to.

L8cruiser

The instructions said unobstructed to the outside of the aircraft. That is what had me confused.

Charlie P.

Keep it away from metal (engine, control rods, etc.) and batteries as much as possible. Most everything else in a model is fairly transparent to radio waves.

JohnBuckner

My Feedback: (1)

Kudoos to you first off for paying it forward

The question about whether or not two antennas are necessary is actually debateable the entire mid range Hitec receivers Optima 7's and of course the lower priced ones the Optima 6's are all single antenna. I have over fifty of the Optima 7 in a wide and eclectic variety of aircraft. In the Hitec line only the Optima 9 receiver has two antennas. I have flown even the Optima 7 (single antenna) in two jet turbines but now use the Optima 9 not because of the antennas but am running out of channels. In fact even recently had to go to Futaba 14FG and receiver because of a lack of channels, of course that rx has two antennas.

So the answer to your question is really maybe, maybe not. If the receiver is designed with a single antenna I would not be afraid of it for most stuff.

John

Rodney

From a technical standpoint, dual antenna (if properly installed) does have an advantage over the single antenna. Reason, if the two antenna are mounted so that the active portion (that last 28 to 35mm bare end) are at right angles you have a better chance of NEVER having a loss of signal due to polarization. With a single antenna, if the receiver antenna is pointed directly at the transmitter antenna, the signal reception is at it's weakest and has been known to cause momentary loss of signal. Also, if there is a bit of coax in each antenna run, there is less chance of both antenna being masked by having any object in the plane (motor, battery, other conductive media) between the transmitter and the receiver. A good example of this being bad is, it the antenna is directly aft of the motor and battery and you are coming in for a landing, that antenna may be blanked from your transmitter; not a good place for that to happen.

JohnBuckner

My Feedback: (1)

Of course Rodney I am sure everything you are saying is absolutely true ----"from a technical standpoint" However I am speaking from a 'practical standpoint' and when you get right down to it the point is certainly debatable. You do not need a two hundred dollar two antenna receiver on most airplanes and hitec has proved it The Optima 7 single antenna Rx is my go to unit for most everything with something over fifty of them in use in my fleet and then just a few Futaba 14's and Optima 9's. Reliabilty or performance has not ever been a problem.

John

Charlie P.

One expedient I use to keep my dual antennas at 90° is to cut a square of cereal box cardboard and use masking tape to attach the antennas along two edges. Then I use two-sided tape to hold this to the side of the model's fuselage.

I just bought the Multiplex Pilatus and the receiver has to be installed through a 3/4" by 2" opening in the underside. It's like doing arthroscopic surgery. I was able to tack the antennas of my receiver with a dab of hot-melt glue applied using the end of a bamboo skewer. Worked very well and may be my solution henceforth. Two little dabs and it's done (and easily removable).

Top_Gunn

My Feedback: (6)

Perhaps I misread the original post. I assumed the receiver he has is a two-antenna receiver, and he wondered if he should use both of them. If that was the question, I think the answer is "yes." There's nothing to be gained by not doing that. If it's a radio that came with just one antenna, that's a different question.

Gray Beard

My Feedback: (-1)

The antenna?? Like John said, some have two and some have a single, use whatever they come with. Where to mount the 2.4, anyplace you want. I have now mounted them on top of the battery, on the side of the ignition and under push rods. My electric has it mounted outside of the plane right next to the battery and under a push rod. 2.4 makes a lot of the old RF problems a thing of the past.
I have seen a number of the JR systems using more then one receiver.