PASCO PI-8127 Function Generator - Manual (Page 5)

®
Model No.PI-8127 Operation
5
Continue to turn the Voltage Adjust knob counterclockwise to reveal the next five
waveform choices: External, Mod Sine, Mod Triangle, Mod Pos Ramp, and Mod Neg
Ramp. (“Mod” is an abbreviation for “modulated”.)
External Input: The External waveform choice corresponds to the use of an external
input to the Function Generator. The generator has positive and negative input jacks
on the rear panel. Maximum input voltage is ±10 V. The Function Generator amplifies
the power of the input signal up to a maximum of 10 watts (up to 1 amp at up to 10
volts), expressed as a percentage of maximum. Turn the Voltage Adjust knob to
decrease or increase the power amplification.
Modulated Waveforms: The modulated (Mod) waveform choices also correspond
to the use of an external input to the Function Generator through the input jacks on
the rear panel. When a modulated (Mod) waveform is selected, the signal produced
by the Function Generator will be multiplied by the signal from the external input.
Change the frequency of the Function Generator’s signal with the Frequency Adjust
knob. Adjust the percent modulation with the Voltage Adjust knob. The formula for
the percent modulation is based on the amplitudes of the peak (P) and the trough (T)
of the modulated signal.
When the percent modulation is 100%, the trough amplitude is zero.
Menus
Press the MENU button to show the list of choices: V Offset (voltage offset), V Limit
(voltage limit), I Limit (short circuit current limit), Backlight, and Sweep. The pointer
is at V Offset. Turn the Voltage Adjust knob to move the pointer up or down among
the choices. Press the Voltage Adjust knob as if it were a button to select a choice.
DC voltage
adjust
screen
Last WAVEFORM menu
External
waveform
display
Mod Sine
waveform
display
percent modulation
P - T
P +T
------------ 100 × =
Mod Sine waveform. Input signal
is 1 kHz at 2.00 V. Mod Sine signal
is 0.100 kHz at 100%.
MENU choices
Percent
modulation