Dual receivers cause reduced range?
Aerografixs. I must respectfully disagree with several of your points.
First, let me state that my objective in using dual Rx's is to reduce the chance of a single point failure in the on board system causing loss of control of the aircraft. The 2nd Rx is used in conjunction with a split servo arrangement and separate batteries and switch's for each Rx.
Now to my disagreements:
1. Parallel rx/servo/battery/switch schemes have been around for a long time and pre-date the use of a dual rx to split the current. I my self have used this scheme in several large airplanes for years and have done so purely for reliability considerations. It has nothing whatsoever to do with current splitting
2. New technology has improved reliability to a degree but by no means has it eliminated failures. On of my most recent failures was a new MPX 9 channel IPD rx from an MPX 4000 system. I also had a failure in a brand new Tx.
3. Separate batteries for the servos and Rx actually decrease system reliability from the point of view of a single point failure causing loss of control. With this scheme you have two batteries, but the failure of either one will cause loss of control. A parallel battery arrangement allows the failure of either battery without loss of control
4. One of my failures was caused by a component in the system that failed at elevated ambient temperature but worked at room temperature, a problem like this is very difficult to detect how carefully you inspect or install your equipment.
Careful maintenance and inspection is no guarantee that you will not be the victim of a random failure of a component in the Rx. or elsewhere.
5. I install my Rx's wrapped loosely in thick foam, watch my antenna routing, be careful not to place stress on wires, secure my foam pack in the fuse, do frequent range checks, check voltage before every flight, etc, etc, etc. I take pretty good care of my fleet and am mildly resentful that you would imply otherwise.
6. I agree, transmitters do fail, but a dual Tx arrangement is much more difficult and complex than a dual rx. One was marketed several years ago for the old Kraft systems. If one was available today I would look be interested in it.
7. I can see that the addition of a fiber optic link would help with problems arising from voltage drop and induced noise in long servo leads but, exclusive of those issues, I do not see it guarding against loss of control due to a single point failure. Quite the contrary, the optical couplers themselves add complexity and additional components to the system.
A parallel system is not something I use in all planes. It is only used where the plane is particularly valuable to me and when it is large enough to carry the extra weight. It has saved at least one plane for me and is well worth the extra time and expense.