Installation guide

Troubleshooting
Troubleshooting Pulse Modulation and LF Out
1-107
Troubleshooting Pulse Modulation and LF Out
The pulse waveform originates on the A23 Motherboard, is routed through the A18 Reference, and then is
routed out to the A13 Output and A14 Extended Frequency Output (Option 506). When pulse modulation is
switched on, the pulse waveform is used to turn on and off the burst modulator on the A13 Output and A14
Extended Frequency Output (Option 506).
To configure the signal generator for pulse mode and check the pulse waveform on an oscilloscope from the
front panel LF Out:
1. Press the
Pulse hardkey and the Pulse On softkey.
2. Press the
LF Out hardkey and the LF Out On softkey.
3. Press the
LF Out Amplitude softkey and use the numeric keypad to enter 5 Vp.
There should be a square wave on the oscilloscope with a period of 80 us and an amplitude of
approximately 10 Vpp. The period and pulse width of the pulse waveform may be varied using softkeys
under the
Pulse menu.
• If the pulse waveform is good at the LF Out port, check it at the A19 Daughterboard with one of the
following procedures:
— “To Verify the Pulse Waveform at the A19 Daughterboard (All Options)” on page 1-108
— “To Verify the Pulse Waveform at the A19 Daughterboard (Option 506 Only)” on page 1-110
• If there is no pulse waveform at the LF Out port, proceed to “No Pulse Signal from LF Out” on
page 1-112.