The Model 178 Programmable Waveform Synthesizer is a 1 µHz
to 50 MHz multifunction sweep Synthesizer that can operate
as a trigger, gate or burst Generator at levels to 20 volts
peak-to-peak. It is synthesized to 8 digits in all modes.
Its main Generator, an 8 digit 50 MHz Synthesizer, produces
sine and square waves and, at reduced frequencies,
triangles, ramps, pulses and haverwaves.
An external reference input can phase lock the Synthesizer
by locking the reference source. Phase locking allows the
Synthesizer to operate as a variphase Generator with phase
offset in 0.010 increments.
The output level is specified into a 500 load from 1 mV to
20 Vp-p with 3 digits resolution, DC offset can be
programmed to vary the waveform base line ±10V. Amplitude is
displayed in units of Vp-p, Vrms or dBm for any waveform.
The internal sweep Generator varies the main Generator
frequency (lineariy or logarithmically) between the start
and stop frequencies. The sweep Generator has its own
operating modes: triggered, gated, hold at start and hold at
stop. In addition, ten programmable frequency markers,
available one at a time, can be used to indicate critical
frequencies within the sweep. The sweep Generator can
internally trigger the main Generator to produce pulses with
a 10 ms to 10 min. repetition rate and 5 ^s to 5 days pulse
Two external inputs may be used to phase- or
ampiitude-modulate the Synthesizer, if the Synthesizer is
phase modulated, the main Generator (when operating at
frequencies above 500 kHz) varies up to ±360°. When
amplitude modulated, the output can be modulated up to 200%.
Data entry is from the front panel or GPIB with
microprocessors controlling the data. Numeric input is
entered in free format: fixed, floating or exponential
notation. Parameters may be entered in any order.
Internally, all entries are checked for errors and
interactively displayed on the front panel.
Up to 5 complete sets of programming may be stored and
Option 001 allows up to 40 sets of complete front panel
settings to be stored in memory. Memory is battery backed up
(internally recharged) for 60 days (minimum) retention of
settings. Memory is expandable to 240 settings.
Option 002 provides an additional high stability frequency
reference crystal for greater accuracy. The high stability
frequency has an accuracy of ±5 x 10_8 and an aging rate of
5 x 10~s/day (average) or <4 x 10~8/ week.