RCIGN,
I have a question or two,
I have a ZDZ-80 & 50. Both have E/I Last weekend one of my friends ( who also has an 80 & a few of us share a big Hots to break in engines) was on his second flight when he lost his throttle (went to 1/4 or idle) and ended up mostly crashing the Hots. He was told by some of the other guys that he should not have had the throttle servo on the firewall as it got RF from the ignition. I had set the plane up for the 80 and flew 4 gals through it with no problems. He had exactly the same set up and went 'boink'. I am using an Airtronics Stylus on PCM and he is using a Futaba 8 ch on FM (both of us are using Hithech servos). Do you know what gives?
Part two: (Same Radio, same type rec)
I have my 50 installed in a Pica P40. 1800mil batt's for each for the rec and the ign. they are up near the front behind the engine compartment the ign batt is by the ign unit on the starboard side, and the rec batt is on the port side. The distance between them is approx 6". However, both power wires run to the top of the comaprtment and back through a tunnel to the switches (which are about 1" from each other) in the radio area. The switches are approx 6-8" from the reciever. I have one flight (due to weather)on the P-40 and did not experience one problem (yet?) with my set up. I'm a Mechanical Engineer (not Electrical) and I thought the only RF would come (or originate) from the Ign unit and/or the lead to the plug. I have since been told, that it will migrate through all the connections back through the switch harness and batt pack. If this is so, I presume anything adjacent to those wires will be exposed (which would be my other swich harness, and the wires running up to the forward compartment (rec batt)) to RF.
Boy, oh Boy, Am I confused now.
Atmospherics may play a part occasionally, but how come I'm ok(so far)???

rpike,
I've been flying ignition powered engines in giant scale planes since 1982 and have always kept my receiver system (receiver, switches, servos, batteries) as far behind the firewall as possible and have not had interference problems from the ignition. As of late I've noticed that there is a trend toward mounting the throttle servo in the engine compartment especially where people are using ZDZ rear carb engines. This is probably so that the most precise control can be obtained for the throttle position. Some are using opto isolators to isolate from ignition noise. I'm not really sure how well this works.

I have a ZDZ80 on order and plan to make a zero slop 90 degree bell crank to use with it on the throttle unless I get my mind changed. That way I can mount the throttle servo back in the cabin area in the usual place and continue to maintain the RF isolation.

Sure hope Ralph (Rcign) jumps in here with his words of wisdom.

Ken

My words of wisdom..Keep the ignition battery and switch as close to the engine as possible, as far away from the receiver and battery as possible...Most of my conversions put the ignition inside the mount, so the spark plug wire is only about 4 inches long, with a rubber boot...I use a nyrod from the throttle servo to the engine..the throttle servo is about on the c.g. of the plane..All my conversions use a rotated carb so that the nyrod is a straight shot to the servo without bell cranks....
Check out the C&H website for the best info on interference....

RCIGN,
What is the address of the C&H website?
and, what do you know about the RF feedback I asked about?
thanks,

www.ch-ignitions.com
My total knowledge of electronics is..
Buy the boards from Harmon electronics, already drilled..
solder the correct parts in the correct place..
If it is done right, it works....
Red to plus and Black to minus..
Sensor wiring, looking at the sensor with the numbers up, leads to left, red wire on top, black in the middle, white on bottom...
Don't connect the battery backwards, it blows the first diode in the circuit..
Center is red, closest to center is black, farthest from center is white (or other color) on Dean's connectors...