General Description; Specifications - Wavetek 188 Manual

11 THE MODEL 188
Тһе Wavetek Model 188, 4 MHz Sweep/Function
Generator, is a precision source of sine, triangle and
square waveforms plus dc voltage. All waveforms are
front panel variable from 4 mHz to 4 MHz and can be
internally or externally modulated. Frequencies are
variable linearly or logarithmically within a frequency
range. When used as a sweep generator, an internal
ramp generator provides a recurring sweep over a
1000:1 (linear) frequency range or 10,000:1
(logarithmic) frequency range. Output can be con-
tinuous or the generator can be triggered or gated by
an external signal or a front panel switch. Amplitude
of the waveforms is variable form 10V peak-to-peak in-
to 500 down to 15 mV peak-to-peak. DC reference of
the waveform can be offset positively or negatively.
The two selectable waveform outputs are a 20V peak-
to-peak maximum and a 2V peak-to-peak maximum
(20 dB down from 20 Vp-p); both may be varied over a
30 dB range. Auxiliary outputs are a TTL level sync, a
6000 sweep ramp and а 6000 generator control
voltage signal whose level is proportional to the main
generator frequency.
1.2 SPECIFICATIONS
1.2.1 Versatility
Waveforms
Sine Лу ,triangle ^v ,square
and dc.
n
u ,TTL pulse лп
Operational Modes
Continuous: Generator runs continuously at selected
frequency.
Triggered: Generator is quiescent until triggered by
external signal or manual trigger, then generates one
complete waveform cycle at selected frequency.
Gated: As triggered mode, except output continues
for duration of gate signal. Last waveform started is
completed.
SECTION 1
GENERAL DESCRIPTION
Sweep: An internal ramp generator will sweep the
main generator from a lower, start frequency to a
higher stop frequency, linearly (3 decades) or
logarithmically (4 decades).
Sweep Stop: Frequency switches to high sweep limit.
Used to set high frequency limit.
Frequency Range
0.004 Hz linear (0.0004 Hz log) to 4 MHz in 7 overlap-
ping decade ranges:
POR M И ee d 0.004 (0.0004) to 4 Hz
A AS DE 0.04 (0.004) to 40 Hz
100 ues р Men} 0.4 (0.04) to 400 Hz
УК ast EZ: o s о р . . 4 (0.4) Hz to 4 kHz
CELO Кон скен aur са LUN 40 (4) Hz to 40 kHz
OA а И 400 (40) Hz to 400 kHz
XML See ааа Оно МНА
Function Output
^, , ^v , Пи selectable and variable to 20 Vp-p
(10 Vp-p into 500) HI output, and to 2 Vp-p (1 Vp-p into
500) LO output. Both outputs varied with a 30 dB ver-
nier. Peak output current is 100 mA maximum (НІ out-
put) into 500 (200 mA peak into a short circuit). Source
impedance is 500.
DC Offset and DC Output
Waveform offset and dc output selectable and variable
through HI and LO BNC outputs. DC output selectable
by not selecting a waveform function. НІ output is
+ 10V max (+ 5V into 500) as offset or Мас output.
Signal-peak plus offset limited to +10V (+ 5М into
500). LO output is + 1V max (+ 0.5% into 500) as is
signal-peak plus offset limit. DC offset plus waveform
attenuated proportionately at LO ( — 20 dB) output.
TTL Sync Output
TTL pulse (5096 duty cycle) at generator frequency.
Drives up to 20 TTL loads.
GCV — Generator Control Voltage
0 to 4.0V open circuit output from 6000 source im-
pedance. Proportional to frequency of main
generator. For use as a horizontal drive signal.
1-1