The APELC rackmount trigger generator utilizes a thyratron-based pulse forming circuit to provide a 18-kV trigger pulse to the Marx generator.  The trigger generator provides LED indicators on the front panel for notification of thyratron HVPS conditions. Two diagnostics, thyratron HVPS current out and thyratron HVPS voltage out are available on the front panel of the trigger unit.  These two signals can be monitored on any 1- MΩ oscilloscope channel or handheld DVM by connecting to the BNC jacks on the front panel shown below.

Input power 100-250 VAC, 47-63 Hz
Max Current:
Maximum line current 90-140 VAC: 1.5A
180-250 VAC: 0.9A
Output voltage 18 kV onto 50-ohm cable
Voltage risetime <100 ns
Output connection Coaxial high-voltage quick disconnect or custom


 The front panel shown aboveincludes: (A) hand-held fiber-optic remote, (B) fiber optic ST connections, (C) thyratron HVPS status indicators, (D) thyratron heater switch, (E) HVPS power switch, (F) thyratron voltage and current diagnostics.

(A)    Handheld Remote Control

The handheld remote connects to the trigger generator via and 65/125 um multi-mode fiber ST connectors. The remote allows thyratron circuit charging and system triggering from a standoff distance.

(B)     Fiber optic connectors

The trigger fiber-optic input jack connects to the handheld remote uses ST connectors.

(C)     LED Thyratron HVPS Indicators

These LEDs indicate the state of the Thryatron circuit’s HVPS

(D)    Thyratron Heater Power Switch

This switch controls power to the thyratron heater, power supply control circuitry, and low-voltage pulse generator circuitry.  The thyratron has a minimum tube heating time of 4 minutes.  The thyratron heater power is indicated by a LED housed in the switch and must be turned on at least 4 minutes prior to operating the system.

This switch must always be turned on before and turned off after the High Voltage Power Switch or the Marx Generator HVPS power.  This switch provides power for the control circuitry which inhibits the system’s high voltage power supplies.

(E)     Thyratron HVPS high voltage power switch

The thyratron HVPS high-voltage power switch connects the trigger unit’s internal power supply to prime power.  Pulse generation cannot take place until this switch is actuated.  Power to the internal HVPS is indicated by a red LED housed in the switch. Even though the high voltage switch is turned on, the thyratron will not be charged until a signal is received from the delay generator. 

(F)     Thyratron HVPS Analog Output

The thyratron HVPS analog output jacks provide the current and voltage waveform of the thyratron charging and discharging during a trigger cycle as controlled by the handheld remote.  The voltage ratio of the measured waveform is 4 kV/V.


This item is subject to ITAR regulations.