[evlatests] New (?) Ka-band birdie

[Rick Perley]

     In data taken in both B and A configurations, I find a strong (> 
500 Jy in 2 MHz channelwidth) birdie at:

     30976 = 242*128 MHz.

     So it looks like a harmonic of 128 MHz ... but ... there are *no* 
other birdies visible in the entire 8 GHz width (30.5 through 38.5 GHz).

     I can't find this in my old spectral sweeps.