Universitatea POLITEHNICA din Timişoara
Facultatea de Electronică şi Telecomunicaţii
Departamentul Măsurări şi Electronică Optică
www.meo.etc.upt.ro
Function Generator HAMEG 8130
1. Introduction
Function Generator HAMEG 8130 is a highly versatile, all-purpose signal source which can be used to generate different built-in waveforms or arbitrary waveforms (user-generated). All arbitrary waveform data are stored in a non-volatile memory. A DC offset can be introduced over the generated waveform.
Data transfer is possible via the built-in IEEE-488 or RS-232 interfaces. Also an optional external keyboard can be used for entering different commands.
HM 8130 Generator can generate waveforms whose frequency is linear-variable with the time (the Sweep function). There are inputs available for amplitude modulation, signal amplitude control using a DC voltage. Beside the standard operating mode (continuous), the device can be used in trigger and gate mode.
Specifications for HM8130:
Frequency Pulse Sampling Rise-/ Waveform Amplitude Range Width Rate Falltime
SINE 10mHz-10MHz 0-20 Vvv
SQUARE 10mHz-10MHz 0-20 Vvv <10ns
RAMP* 10mhz-10Khz 0-20 Vvv
TRIANGLE* 10mhz-100Khz 0-20 Vvv
ARBITRARY* 10mhz-100Khz 0-20 Vvv 10MHZ
PULSE* 10mhz-5Khz 0-20 Vvv 100ns-80s <10ns
* digital signal generated
HM 8130 front panel:
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Universitatea POLITEHNICA din Timişoara
Facultatea de Electronică şi Telecomunicaţii
Departamentul Măsurări şi Electronică Optică
www.meo.etc.upt.ro
1. Power
2. Remote / local (the Remote LED is lit when the instrument is operating via IEEE-488
bus)
3. External keyboard
4. Input for Gate and Trig signals 5. Selection of operating mode
6. Selection of waveform
7. Digital display (output voltage is indicated as Peak-to-Peak-Voltage with open circuit)
8. Selection of parameters for Sweep Mode 9. Dial for setting of selected value 10. Pushbuttons and LED’s for setting of parameters
11. Decadic range of parameters
12. Offset – activate the offset function 13. Invert – inversion of offset and pulses 14. Output ON/OFF
15. Output BNC (impedance 50Ω)
HM 8130 back panel:
16. Address selector for interface 17. Connector for either IEEE-488 or RS232 18. AMPL. CONTROL – analog modulation input 19. Sweep out (saw-tooth output)
20. Trigger output
21. Mains connector, voltage selector and fuse
Operating modes
1. Continuous mode
The continuous mode can be selected by pressing “5” until CONT LED is lit.
In this mode all 6 waveforms (sine, square, pulse, ramp, triangle and arbitrary) can be
generated.
The offset can be set depending on the amplitude of the generated signal:
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Universitatea POLITEHNICA din Timişoara
Facultatea de Electronică şi Telecomunicaţii
Departamentul Măsurări şi Electronică Optică
www.meo.etc.upt.ro
Amplitude (open circuit) Offset
2,1V-20V ?7,5V
0,21V-2V ?0,75V
20mV-200mV ?75mV
The waveform can be reversed by pressing button INVERT (13).
If the waveform generated is pulse, the maximum pulse width is defined by the following formula:
Pulse width= 0.8/frequency
SWEEP function
This feature allows generating signals with variable frequency. By enabling this feature, the frequency of the generated signal changes linear by time between two frequencies which can be set with buttons START and STOP. Both START and STOP values must be in frequency ranges 10mHz – 550Khz or 450Khz – 10Mhz. The transition time between the two frequencies can be set by pressing TIME button. The signal corresponding to the sweep pattern is available at the BNC jack SWEEP OUT (19).
Controlling the amplitude of the output signal
The output voltage can be reduced by applying a DC signal between 0 and +5 V at AMPL. CONTROL jack (18). The output voltage can be calculated using the following equation:
Vout=Vdisplay*K,
where K=(5V-external DC voltage)/5
However, the displayed output voltage remains unchanged.
Amplitude modulation
The amplitude modulation can be done by applying an external signal to the AMPL. CONTROL jack (18). This represents the modulator signal and must be a bipolar signal with 2.5V offset.
Arbitrary function
Arbitrary signals can be digitally generated using the integrated D/A converter and stored in internal memory. The signals can be defined using the interface or the optional keyboard.
The default waveform for this function is a damped sine.
2. Gate/Trigger Mode
In this mode, the output signal is controlled by a TTL signal applied to the gate/trigger input (4)
In gate mode, the output signal is generated at the output only when the input signal is “high”. When a “low” signal is applied to the input, no signal is output.
The trigger mode works with all signal functions. In this mode at most one signal period is generated, which starts when the input signal goes from “low” to “high”. If “high” is present at input
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Universitatea POLITEHNICA din Timişoara
Facultatea de Electronică şi Telecomunicaţii
Departamentul Măsurări şi Electronică Optică
www.meo.etc.upt.ro
longer than a signal period (according to the frequency that was set), at least one more period will be generated. From the moment when the last period of generated signal ended the output will be 0 until a “low-high” transition take place at the trigger input. Maximum frequency for the output signal is 500kHz for sine, square and pulse waveform.
Exercises
1. In the continuous mode you have to generate all available waveform, with/without offset.
The output will be viewed on the oscilloscope. In which case the INVERT function will
be visible?
2. You have to generate a sine wave using the SWEEP function and view it on the scope.
Then you have to view the SWEEP OUT (19) signal. You have to choose a triggering
mode for the scope to obtain a more stable image for both signals. Hint: time parameter
for this function must be set to the minimum value.
3. You have to control the amplitude of the output signal using a DC source. Please verify
the output voltage using the formula.
4. You have to obtain an amplitude modulated signal using another signal generator, both
signals to be sine wave. For example the frequencies will be in 1:10 report. Please
calculate the modulation factor using the following formula:
m = (Amax - Amin) / (Amax + Amin).
5. You have to generate a square signal and a pulse signal. The output will be viewed on the
scope, for offset equal to 0. Please draw on paper the waveforms, specifying in each case
the 0 level.
6. You have to generate a TTL compatible signal:
a) using square waveform
b) using pulse waveform
7. What signal is generated by HM 8130 in gate/trig mode, if the waveform is set to sine,
and a pulse signal with double frequency and pulse duty factor 1/10 is applied at input?
Please check it practical.
8. You have to obtain the following signals using trigger mode:
a) a signal which contain in a period: two complete sine waves, each 1ms long and a
3 ms time in which the signal should be 0 volts.
b) a sine-wave signal with frequency 5kHz (without interrupts)
c) a sine-wave signal with half frequency that the input signal
d) a signal with following shape:
11 2 1 .. 5 T
All numbers represents milliseconds.
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