20 seconds of continuous bat activity.
Details show a bug zap during the first 1.5 sec (see Picture 2)
Magnification of 0-1.5 s region of Picture 1.
0805-5b (1s, 8 kb mp3)
The pulse train speeds up to a maximum, then silence ... for .2 seconds.
Is that enough time to swallow a bug?
Magnification of region around 17 s in Picture 1.
0805-5c (1.9s, 12 kb mp3)
Several high frequency pulses. The sonogram shows energy peaks
around as 4.75 khz audio, 76 khz ultrasound with energy still
present one octave higher, around 152 khz.
Magnification of seconds 19-20 of Picture 1.
0805-5d (1.9s, 12 kb mp3)
It looks like a blob, but it sounds strange and under higher magnification
(next Picture) this proves to be a very fast pulse train,
of the type first seen in 0805-1.
Picture 5 -- Time axis in audio samples, 32000 samples = 1 sec
Magnification of seconds 0.55 to 0.75 of Picture 4.
This closeup resolves part of previous picture into a fast pulse train
with 17 pulses over 1/10 th of a second (3200 samples),
for a pulse rate of 170 hz. the highest we've seen yet.
The sonogram indicates an ultrasound frequency of 2.25*16 = 36 khz.