r. king    june 1977  subroutine ferfrq
calculate transmitter frequencies for vlbi n-count
observable, either for alsep observations using the mit
differential doppler reciever (ddr), or pioneer-venus
multiprobe observations using the jpl digital recording
assembly (dra) and bandwidth reduction assembly (bra).

nrvfrq= 0  instantaneous received frequencies not available
at the epoch of observation, calculate the
average over the count interval from phase
nrvfrq= 1  instantaneous received frequencies available
at the epoch of observation. use these to calcula
the transmitter frequencies.  however, if
con(16) for a spacecraft is.gt.0, the
xmtr. freq. calculated using received freq.
is overridden by the input power series.

correct xmtr freq for drift, either over the count interval
or over the light time difference between stations
save xmtr freq for ft1dot calculation at next observation
---freqts(1) set eq. freqtl(1) in fermtr if pt not deleted

transmitted frequencies are measured in terms of clock time at
site no. ifrq.  therefore they should logically be corrected for
fdev and rate of ct-at.  this amounts to a small error in the
overall scale factor and hence is ignored.