[Discuss-gnuradio] switching between signal and reference source

[Marcus D. Leech]

I'm buliding a system that switches the RF input, several times per
second, between the actual
  signal, and a stable reference source.

On a USRP2, what kind of latency is there between the antenna input, and
data arriving at the
  head of the signal processing chain?

Small errors at the 'edge' of the switching time are acceptable, but I
don't want to get into a situation
  where my *notion* of whether the input is connected to the source or
the reference is horribly
  out of what.

Can I use the GPIO stuff to give me better confidence of adequate
synchronization between the
  actual data, and the state of the input?

-- 
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org