Model 22 is a closed-loop, frequency stabilized,
sweep/function generator. Both short term and long term
frequency accuracy is 0.09% over its 10OjiHzto 11 MHz
Modes are continuous, triggered, gated, sweep set,
continuous sweep and triggered sweep. Output levels are to
20V peak-to-peak (10 Vp-p into 50Q).
Waveforms are sine, triangle, square, ramp up, ramp down,
and dc. Above 1.1 kHz waveforms are analog generated; below,
waveforms are digitally synthesized.
An LCD display shows frequency (31/2 digits plus unit of
measure) and annunciators that indicate selected operating
modes, etc. The waveform output circuit is protected from
accidental application of high voltage to the BNC connector.
1.2.1 Versatility Waveforms
A bidirectional pushbutton switch selects sine, triangle,
square and dc and for frequencies on or below the 1,100 kHz
range, ramp up and ramp down.
Continuous: Generator runs continuously at selected
frequency. Continuous frequency and sweep start frequency
set with Frequency Course and Fine controls.
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.
Set: Generator runs continuously at sweep stop frequency set
by Sweep Set control. Sweep stop frequency is displayed.
Sweep: Generator frequency is swept from the start frequency
limit set by the Frequency control to the stop
frequency limit set by the Sweep Set control in a
continuously occurring sweep. Sweep Time and lines
logarithmic sweep are selectable.
100 µHz to 11 MHz in 9 overlapping decade ram Range
switching with bidirectional switch with frequency digits,
decimal and units displayed on LCD display. E decade range
capable of 1100:1 frequency change controlled by the
Frequency Course and Fine control.
Waveform amplitude variable over a 20 dB range 20 Vp-p (10
Vp-p into 50Ω) at Function Out. Wave also present at
Function Out (-20 dB) with a fixed 2< attenuation relative
to the Function Out for a full of amplitude range. Peak
output current is 1OOmA minimum at Function Out. Source
impedance of both puts is 50Ω.
DC Offset and DC Output
Waveform offset and dc output variable with DC 01 control
with off position for calibrated zero offset. Function Out
is ± 10V maximum (± 5V into 50Q) as offs* Vdc output. Signal
peak plus off set limited to ± 10V(: into 50Q). DC offset
plus waveform attenuated proportionately at Function Out
TTL pulse (50% duty cycle) at generator frequency drive 10
LS TTL loads.
VCG — Voltage Controlled Generator
Up to 1100:1 frequency change with external 0 to ±5V signal
applied to VCG IN connector. Upper and lower frequencies
limited to maximum and minimum of selected range. Input
impedance is 5kQ and maximum slew rate is 0.1 V/µs. VCG IN
is disconnected when the Stabilizer is enabled.
Trigger and Gate
External TTL compatible signal at Trig In BNC triggers or
gates generator output when generator is in trigger, gate or
triggered sweep mode. Generator triggers on positive edge of
input or gates on for duration of high level input. External
signal pulse width is 50 ns minimum with a maximum
repetition rate of 5 MHz.
When selected, the generator frequency is stabilized at the
displayed frequency to a crystal-controlled reference.
When the stabilizer is on, long term frequency stability is
corrected to the displayed frequency over the entire
operating temperature range of 0 to "f-50°C. The stabilizer
is automatically turned off when the mode is taken out of
continuous or when Log frequency is enabled.
1100 count LCD frequency display with frequency ranging
units (mHz, Hz, kHz, and MHz) and a floating decimal point.
Annunciators indicate selection of waveform, stabilizer
status, generator mode, sweep time and linear or logarithmic
Square waveform variation from 1100 to 100 counts on display
± 0.1 % to 1.100 kHz (across bottom five specified ranges),
±1 % to 110.0 kHz,
±5% to 11.00 MHz.
1.2.3 Amplitude Precision Sine Variation with Frequency
± 0.2 dB on ail ranges up through the 110.0 kHz range,
±1.5 dB to 11.00 MHz.
Referenced to 1 kHz.
1.2.4 Waveform Characteristics Sine Distortion
<0.5% THD up through the 11.00 kHz range.
<1.0% THD on 110.0 kHz range.
All harmonics 40 dB below fundamental on 1.100 MHz range,
and 28 dB below fundamental on 11.00 MHz range.
Rise/Fall Time: <22 ns
Total Aberrations: Each peak <5% of p-p amplitude.
>99% to 110.0 kHz.
Sweep Mode: Linear or logarithmic, up to 3 decades.
Sweep Time: Selectable (in seconds) .01 ,.1,1 and 10.
Sweep Output: Output voltage at sweep out connector
proportional to the sum of Frequency control, internal sweep
voltage and external VCG In voltage. Scale factor is 0 to -f
5V (open circuit) linear voltage change from bottom to top
frequency of a range. Source impedance is 600Q for driving
horizontal axis of oscilloscope or recording equipment.
Sweep Width: Up to 1100:1 linear or logarithmic.