Svantek Shawcity SVAN 977C, User Manual

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SVAN 977C User Manual - Appendixes
I/O
– User programmable Analogue Outputs, Digital Input / Output connector
3.5 mm Mini Stereo Jack type (cable plug and instrument socket are shown)
Table C.5.7. Pin out of the 3.5 mm Mini Stereo Jack
Pin Number
Function
1 Analog
Output
2 Digital Input / Output
(*)
Chassis (3) Ground
*depending on instrument set-up
The user may set-up the I/O mode in the screen < Menu> / Instrument / Multifunction I/O :
1. I/O Mode: Analog Out . When this option is selected, the measured signal from the selected channel
is fed to the terminal [1] of the I/O connector. Output voltage, frequency band and the output
impedance are following:
a) Output Voltage:
The output voltage is equal to 1.0 V
RMS
(

5 %) at:
● 120 dB indication of the instrument, on measurement range “L”
● 137 dB, indication of the instrument, on measurement range “H”,
when calibration factor is set to 0.0 dB.
b) Frequency Band (-3 dB): 0.02 Hz
÷ 40 kHz.
c) Output Impedance: 51
Ω / 5%
2. I/O Mode: Analog In
– future feature.
3. I/O Mode: Digital In . When the Ext. Trigger function is activated, the external triggering of the
instrument may be provided. To do that the user should select Trigger: External ( path: <Menu>
/ Measurement / Measurement Trigger ). The external signal for triggering is specified as follows:
a) Trigger voltage threshold level is set to +1 V.
b) Trigger voltage slope ( path: <Menu> / Measurement / Measurement Trigger ) set by the user as
Slope [+] (uprising as default) or Slope [
–]
(falling, auxiliary).
c) Minimal duration of the trigger impulse: 10
μsec.
d) 100
μsec. release time after previous measurement is necessary before next trigger.
e)
Recommended trigger voltage should not exceed ± 5 V.
f) Input impedance in the Digital In mode
– ca. 10 kΩ / 100 pF, ESD type safety.
g) When the instrument is switched-off in the Digital In mode, the voltage impulse on the pin [1] will
be able to switch-on the instrument, however in this case the minimal duration of the trigger
impulse of 100 msec is necessary, with uprising voltage slope.