[evlatests] Strange X-band birdie

[Rick Perley]

    The X-band HercA data have shown an odd birdie, not previously known 
to me. 

    All four IFs show a strong, unresolved (2MHz wide channel) birdie at 
8188 MHz.  But it's visible only on antennas 13, 16, 19, and 26.  Of 
these, it is, by far, strongest on antenna 16. 

    There are apparently no autocorrelation spectra available within 
this dataset -- I had thought that half of the antennas would have them, 
but actually none have.