Not quite fair,
It does matter what other people say, otherwise I wouldn't ask. As for my mind being made up, well ....I can be swayed.

Back to it.
What I don't seem to be able to cope with, everybody says PCM will not stay locked out. Now I have definitely counted out the switch and low voltage. But how do we really know if the signal is lost?
In the case of PCM, to me, there seems no fair way of knowing if the signal is bad, for whatever reason, until it's over. Take my case. Total good ground test range, as per JR's document, which is the only way I know of , batteries good, etc. Plane takes off, goes quite away on the 270 degree turn around, yet went into fail safe, no more than 150 metres out, at approx 100 feet high. I even had time to turn away a little so the TX ariel was at a different angle.

Thanks to all for input