When OUT2 is connected to the AVX-TEK3-TM2 (using the arrangement shown in the
"BASIC TEST ARRANGEMENT, WITH OUTPUT MODULES" section) and a Tektronix
P6042 probe system, waveforms similar to the one shown below will be obtained:
Pulser settings: 10 kHz, +50V, 200 ns PW.
Scope settings: 100 mV/div (= 1 A/div), 40 ns / div.
The "shorting cable" that the probe clamps to represents a small discontinuity in the 50
Ohm transmission line, and causes some reflections to occur. These are observed in
the above waveforms immediately after the rising and falling edges. The ringing
eventually dies out after 80 ns or so. The amplitude and switching times can still be
measured accurately. If the ringing is a problem, it can be largely eliminated by adding
an attenuator directly on OUT2 SMA connector on the front panel (between the SMA
connector and the cable going to the output module). The attenuator will tend to absorb
reflections, but it will also reduce the output amplitude. A 6 dB attenuator will reduce the
amplitude by half, and produce the following waveform (when used with the P6042
probe system):
Pulser settings: 10 kHz, +50V, 200 ns PW.
Scope settings: 100 mV/div (= 1 A/div), 40 ns / div.
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