These pa amete s a e common and define the ope ation egime fo all the
channels. The cu ently set values a e indicated by displays 3 and 7. 4-digit
display 3 is used to indicate the f equency o the numbe of pulses. Please push
knob 6 up to a click to toggle between them. Indicato s 4 and 5 show which
pa amete is displayed at the moment.
HV ON/HV OFF button 1 activates/deactivates the HV system and allows
the gene ation of HV pulses in the active channels. Red LED on the button lights
on if the HV system is active. The gene ato can ope ate in a single pulse,
continuous, and bu st ope ation modes and has both inte nal and exte nal
t igge ing. Button 14 toggles the inte nal and exte nal t igge ing modes. The
cu ently chosen mode is shown by indicato s 13 o 15.
The default values afte powe ing the gene ato a e 10 kHz and 100 pulses
(fo the inte nal t igge ing mode). The efo e, if HV is activated by p essing
button 1 and the inte nal t igge ing mode with the default pa amete s is
chosen, then the following pulse sequence should be gene ated: 10 bu sts
pe second in each channel (100 ms bu sts pe iod), 100 pulses pe bu st,
100 µs inte val between the pulses in a bu st (10 kHz), the bu st length
equal to 10 ms (100 pulses with 100 µs inte val), and the channels a e
shifted in time by 25 ms one elative to anothe .
In the case of inte nal t igge ing, the cont ol system p ovides the qua tz
stabilized t igge ing pulses. The HV output pulses with set pa amete s a e
gene ated in all active channels just afte activating the HV system by HV ON/HV
OFF button 1. The complete list of the p eset f equencies and the p eset numbe of
pulses in a bu st a e shown in Appendix A. If the cu ently set f equency in Hz is
lowe than o equal to the set numbe of pulses in a second (displayed numbe of
pulses value multiplied by 10), then the gene ato ope ates in continuous mode.
Othe wise, it switches into bu st mode automatically. In othe wo ds, the
FREQUENCY pa amete sets the inte val between the pulses, while the
NUMBER OF PULSES sets the bu st length o the numbe of pulses within
100 ms pe iod.
In the exte nal t igge ing mode, the FREQUENCY and NUMBER OF
PULSES pa amete s wo k as the limits fo the exte nal t igge ing pulses. In this
way, the cont ol system p events ove loading and damage to the gene ato o load
in case of imp ope exte nal t igge ing. The FREQUENCY pa amete sets the
maximum allowable exte nal pulse f equency (minimum inte val between the
pulses), and NUMBER OF PULSES sets the maximum numbe of pulses within
each one-second inte val.
The maximum numbe of pulses within 100 ms inte val is limited to 400,
which co esponds to 4000 pulses in a second in each channel. The efo e,
the maximum ope ation f equency in continuous mode is 4 kHz. Highe
epetition ates a e available in bu st mode only.
Use manual of NPG18P14 (NPG18N14) 7
