Ignition battery near rx battery?

[Dantley]

I've done my best to keep my ignition battery as far away from the rx as possible to avoid interference from the ignition. Usually I have my ignition battery mounted on the engine box and the rx batteries in the main portion of the fuse or in the tail. Lately, I have been seeing a lot of set-ups with 3 lithium batteries near each other in the fuse. 2 rx batteries and 1 ignition battery. I was under the impression that this can cause interference. Is there any truth to that?

[MalaysianFlyer]

I have seen one setup where both the receiver and ignition pack were mounted together, and even the switches were placed side by side. The owner did not get any interference over the 15 flights or so that I watched, but I personally would not risk it, as there is always a chance of inteference occuring. It would really be up to you to decide if you wanted to risk it.

[crazyjoe]

I have two receiver packs and one ignition pack all straped together at cg in my yak over 400 flights in three years never had a problem

[Bunky F. Knuckle]

Keep everything atleast 6" away from each other(ignition and Rx related). It you have no other recourse to have the Rx and ignition packs together, then I would suggest running an Isolator.

But try to get thing spaced apart, and you'll be a happy camper!!!

Bunk~

[Ian]

how can a fairly constant current draw cause interference with another battery, again, with a fairly constant current draw? surely that's not possible?

i can understand why you don't want a RX near the ignition unit, as several 1000v is bound to create some interference, but a battery? cant understand that one!

[ckoerner]

	Quote: Originally Posted by Ian
	how can a fairly constant current draw cause interference with another battery, again, with a fairly constant current draw? surely that's not possible? i can understand why you don't want a RX near the ignition unit, as several 1000v is bound to create some interference, but a battery? cant understand that one!

What happens is that there is a lot of noise in an ignition system. This noise can get coupled onto the battery wires coming into the ignition. Then the battery wires act like a transmitting antenna.

[Ian]

ah i see

why not buy the smart fly fibre optic kill switch? be safe and remove any electrical link

[ckoerner]

	Quote: Originally Posted by Ian
	ah i see why not buy the smart fly fibre optic kill switch? be safe and remove any electrical link

That's only for remote ignition turn on/off from the receiver. It isolates the receiver channel you use for turn on/off from the ignition. You still need a battery to power the ignition.

[jaguar bone]

... and then there is 2.4 Ghz. Total elimination of RC generated radio noises concerns.

[Dantley]

anyone hear about interference happening from the rx and ignition batteries being close? i am having CG issues and can resolve it by taking the ignition battery off the engine box and putting it near the rx batteries. Thoughts?

[OverTemp]

I've heard of it happening... noise that it. I've had it myself... I repositioned my RX packs close to the ignition switch/battery and my engine running range checks went way down.

That being said, my unerstanding is that igntions are supposed to be well shielded. Over time this shielding can break down. As it breaks down you can get more and more RF noise generated through any ignition related wiring. If running a PCM RX you may not see this noise until it is strong enough to cause a lockout. I've always used IPD RXs... I can range check in PPM mode periodically to see if I am developing a problem.

My new solution... I'm switching everything to 2.4 GHz. You could strap your RX to the IGN and be fine.