Avtech AV-1010-C-BCT Instructions Manual page 25

Fig. 11
NEGATIVE PULSE GENERATOR MODULE
The module's output is taken from the SMA connector and
fed into SW8. When not in the 100V range, the output is
connected to one of several T attenuators, depending on
the voltage range.
When SW9 is in the NEG position, the module is supplied
with power by
the +24VDC solder
terminal on
the rear of
the module.