20.
21.
22.
23.
24.
25.
26.
27.
28.
Verify that NOISE FREQ HZ vernier control
provides approximately IO: 1 variation in clock
frequency at the NOISE CLOCK connector
(rear panel).
Rotate function selector to
position and
check to assure oscilloscope displays analog
noise.
Check to assure SEQUENCE LENGTH push
buttons vary the length of the sequence of
analog noise. (Use NOISE SYNC connector on
rear panel.)
Connect oscilloscope external trigger cable to
FUNCTION SYNC connector (rear panel) and
set function selector to
position.
Set S/N - N/S (dB) selector to -10 position
and vernier control fully ccw.
Depress MODE - FM push button and check
to assure square waveforms are frequency modu-
lated by analog noise.
Release MODE - FM push button and depress
MODE - S/N push button. Check to assure
square wave and analog noise are mixed.
Depress MODE - N/S push button and rotate
S/N - N/S (dB) selector ccw through each
position, checking for reduction in signal level.
Verify that the S/N - N/S (dB) vernier attenu-
ates the signal approximately 10 dB between
each step of the S/N - N/S (dB) selector.
OPERATING CONTROLS
The operating controls and electrical connections for
the Model 132 are shown in Figures 2-I and 2-2. Each
of the following paragraph numbers corresponds to a
number appearing in Figure 2-1, front panel, or
Figure 2-2, rear panel. The listing below discusses each
control and its function.
FRONT PANEL
1.
FREQ HZ/PWR OFF - Selects one of six dec-
ade ranges from X 10 to X1M for generator
frequency.
This value multiplied by the fre-
quency dial setting (3) gives the output frequen-
cy of the generator. Extreme ccw rotation will
place the switch in the PWR OFF position, turn-
ing off all power to the function and noise
generators. This control has no affect on the
noise frequency.
2.
FREQ VERNIER - Allows precision electronic
control of the signal output frequency. A full
turn of the control is approximately equal to 1%
4
MODE
of full scale. When turned to the full cw position
(CAL), settings on the main dial will be cali-
brated.
Frequency Dial - Allows coarse control of the
signal output frequency.
Frequency Index - Indicates the frequency dial
setting (3) by reading the dial position opposite
the scribe line on the frequency index. The in-
dex is illuminated when power to the unit is on.
Function Selector - Selects the desired function
or noise output. To select
,
, or
waveforms, or
or
noise, the FUNC
push button (7) must be depressed.
OUTPUT VERNIER (dB) - Provides vernier
control of 0 through -20 dB from the OUTPUT
ATTEN (dB) setting (12). This is the fine ad-
justment for the output signal and will attenuate
signal and noise.
FUNC - When depressed, this control allows
the selected waveform or noise, as determined
by the position of the function selector (5), to
be present at the
OUT connector (11).
This push button must also be in the depressed
position for the frequency modulation mode
(10).
S/N - Depressing this push button allows a
calibrated amount of analog noise to be added
to the selected signal, either
,
, or
wave. The signal-to-noise ratio (S/N) is
determined by the S/N - N/S (dB) attenuator
control (13). When in this mode, the peak to
peak signal amplitude is reduced internally, since
adding noise to the signal would overdrive the
output amplifier.
N/S
- Depressing this push button allows a
calibrated amount of the selected signal, either
i
, or
wave, to be added to the
analog noise. The noise-to-signal ratio (N/S) is
determined by the S/N - N/S
attenuator
control (13). When in this mode, the peak to
peak signal amplitude is reduced internally, since
adding the signal to the noise would overdrive
the output amplifier.