Hello
I was wondering if there is a "safe distance" to separate (within reason) the ignition battery, wiring, and switch (CH Ignition) from the rx battery, and wiring. For balance purposes, in my installation, I'd like to put the ignition battery and unit on the outside of the firewall, and the rx battery on the inside of the firewall. I'd also like to put the ignition switch in the fuse near the firewall, as opposed to cutting another hole in the cowl. I've attached a picture (Hopefully) to show where I'm hoping to put the components, and I'd appreciate any feedback on locating the RX battery, rx switch, and Ignition switch. Thanks in advance,
Sam

Sam, the usual answer is to keep all of the receiver components as far away from the engine components as possible. If you have a fully shielded ignition then this might not be completely necessary. I think that's called a conditional maybe.

The final answer depends on the transmitter antenna down range check with the engine off and running. If the engine running doesn't degrade the receiver performance by more than 15% distance then you are probably OK to test fly. If you should have any interference then land immediately. You may then have to re arrange the components.

Ken

In the picture, the throttle servo appears to be too close to the engine.

-ZM

Thanks for the advice. I will move it back to the rear of the former that holds the wing joiner. That should give me about a foot of separation from the engine and ignition. I appreciate you taking the time to help.
Sam

Dad- I would also try to have both the smoke tank and the fuel tank over the center of gravity. That way you will not have a CG change when your fuel is being consumed.

The cg is supposed to be right on the wing joiner, which is an aluminum bar as opposed to a tube. There isn't room under the joiner for the tanks. I thought that if the fuel tank went up front then the smoke tank should go in back. I've got room up front for both without the throttle servo in the way, and there's also room behind the joiner for both. So should I put them together or put one in front and one in back, sort of sandwhiching the joiner? And when I balance, should I balance with both tanks full or empty?
Thanks again for helping a rookie!
Sam

If there is no way to put the tanks over the CG, do exactly what you have planned. Balance with the tanks empty and make sure they are as close to CG as possible. Sandwich them as you have described.

If the tank is ahead of the C.G. than balance it empy. If it is rear of the C.G. balance with the tank full. This way, as the tanks empty the planes balance will change into a more nose heavy condition, which is not a big deal. If it moves to a more tail heavy condition you may find yourself in trouble.

This is how I have the electronics set-up on my 28% Laser 200 with Brison 3.2:

1.) Ignition strapped to bottom of the fuselage immediately behind the firewall. I also went with a shielded Bosch plug cap.
2.) Ignition battery (4.8v 1650 mAh NiMH) strapped to right side of fuselage just behind the firewall. Its corresponding switch is about 3-4" behind the battery.
3.) Receiver battery (6.0v 2700 mAh NiMH) and switch are in the same locations on the left side of the fuselage (directly opposite the ignition battery and switch).
4.) Throttle servo is located 3" or so behind the ignition switch on the right side of the fuselage, connected to the throttle lever with Sullivan golden rod (the black one in the white sleeve).
5.) Receiver (Futaba 149DP PCM) behind everything listed above by several inches at the rear of the hatch. Antenna is run through a tube tied to the inside of the fuselage.
6.) Fuel tank is in front of C.G. right now but I will be installing a smaller tank and will place it under the wing tube on the C.G.
7.) Elevator and rudder servos are in the tail.

This set-up has worked great with no interference problems.