May. 2008 DD-7 5. Turn the D.TIME control clockwise all the way. Verify that while the control is being turned all the way clockwise from the 12 o’clock position, the CHECK LED stays dark. When the control has been turned clockwise all the way, the LED lights up red. 3. Adjust the MODE knob to the MODULATE position. Verify that waveforms like those shown in the figure below are output. fig.DD-7-wave-1.eps_75 The CHECK LED lights up orange. fig.DD-7-wave-1.eps_75 4. Adjust the MODE control to the HOLD position. 4. VR Check (MODE) Verify that waveform output stops. The CHECK LED goes dark. Make the connections shown below to the INPUT and OUTPUT jacks on the DD-7, using the settings indicated.
fig.DD-7-wave-2.eps_75 INPUT A: Input a rectangular wave at 400 Hz, 800 mVp-p. INPUT B: Input a rectangular wave at 400 Hz, 800 mVp-p. OUTPUT A: Connect the oscilloscope. OUTPUT B: Connect the oscilloscope. Set the oscilloscope to 500 mV/DIV, 1 ms/DIV, and coupling: DC. 1. Verify that the MODE control is at the REVERSE position. Verify that waveforms like those shown in the figure below are output. fig.DD-7-wave-1.eps_75 The CHECK LED lights up orange. 5. Adjust the MODE control to the 50 ms position. Verify that waveforms like those shown in the figure below are output. The CHECK LED lights up orange. fig.DD-7-wave-1.eps_75 2. Adjust the MODE knob to the ANALOG position.
Verify that waveform output stops. The CHECK LED goes dark. fig.DD-7-wave-2.eps_75 12