the set number of pulses is less than the set frequency, otherwise, it is in
continuous mode. The complete lists of preset frequencies and number of pulses in
the burst are presented in Appendix A.
External triggering
External triggering mode is set by pressing INT/EXT latching push button. Red
LED on the button lights off, indicating the external triggering mode. The
generator is triggered by the rising edge of the external triggering pulse applied to
BNC type SYNC IN connector. Please use a coaxial cable and triggering
generator with 50 Ohm impedances. Recommended triggering pulse amplitude
and width are +5 V and 1 µs. Red LED on INT/EXT button blinks with 1 Hz
frequency in case of successful triggering. The delay between the triggering pulse
front and the output pulse (internal generator delay) is about 1 µs. Typical jitter
(RMS) is 1 ns.
The maximum allowable pulse repetition rate and the number of pulses
within the burst are limited by internally set FREQUENCY and NUMBER
OF PULSES parameters. Please set the required values by FREQUENCY
knob.
The generator can operate in burst enable mode also. Long triggering pulse
generates a burst of pulses with repetition rate set by FREQUENCY parameter.
The external triggering pulse fed to SYNC IN connector works as enable signal in
this case. HV pulses are generated continuously until the level of the triggering
pulse becomes low.
The single pulse operation is available in the case of external triggering mode
only.
Fig.3 – Fig.10 show the various bursts of the pulses formed in the external
triggering mode.
Triggering test mode
Push and hold for one second the PULSE ENERGY knob to switch into
TRIGGERING TEST mode. HV ON/OFF push button is blocked in this mode,
and HV output pulses are not generated. LED display shows
00
, which means
zero output power. Triggering sequence from internal and/or external source goes
to SYNC OUT connector and can be registered by the external oscilloscope. This
mode is useful to check the triggering sequence, especially in complicated
operation regimes. Push and hold for one second the PULSE ENERGY knob one
more time for returning back to the normal operation mode.
MEGAIMPULSE LTD. 12
