[hpsdr] Angelia external clock input?

[Jim Barber]

I've seen differing opinions as to whether the external clock input on
Angelia (original ANAN 100D in this case) can be driven reliably without 
modification.

Is there any consensus as to whether it can be used and stay in lock 
reliably,
and if so what level should be applied? If not, I'll continue to explore 
the daughtercard option.

Thanks,
Jim N7CXI