Quantum 9412 Manual 

Model 9412/9412A pulse generator. Rather than the usual array of knobs and switches, the 9412/9412A uses a menu-driven user interface with "on-line" help -- once you learn the basics of operating your 9412/9412A, you may never need to refer to this manual again. The 9412/9412A has some unique features that are designed exclusively for use as a laser trigger signal generator, but can also be used as a general purpose pulse generator. Because it employs a flexible microprocessor-controlled architecture, the 9412/9412A can be custom- ized to fit your exact requirements -- contact Quantum Composers for details. Technical Support For questions or comments about operating the 9412/9412A, contact Quantum Composers via one of the following methods: P Phone - (406) 582-0227 P Fax / Modem - (406) 582-0237 P Email/Internet - www.quantumcomposers.com Parts List The following parts are included with the 9412/9412A -- contact Quantum Composers if any parts are missing: P 9412/9412A Pulse Generator P AC Power Cord P User's Manual P Quick Reference Card Warranty In addition to a 30-day money back guarantee, the 9412/9412A has a one-year limited war- ranty from the date of delivery. This warranty covers defects in material and workmanship. Quantum Composers will repair or replace any defective unit. Contact us for information on obtaining warranty service.

interface. New features and operating modes often can be added, without hardware modifi- cations, by merely modifying the software contained inside the 9412/9412A. Most modifica- tions can be made for a very modest charge -- contact Quantum Composers for details. Safety Issues Normal use of test equipment exposes you to a certain amount of danger from electrical shock because testing must be performed where exposed voltage is present. An electrical shock causing 10 milliamps of current to pass through the heart will stop most human heart- beats. Voltage as low as 35 VDC or RMS AC should be considered dangerous and hazardous since it can produce a lethal current under certain conditions. Higher voltages pose an even greater threat because such voltage can more easily produce a lethal current. Your normal work habits should include all accepted practices that will prevent contact with exposed high voltage, and that will steer current away from your heart in case of accidental contact with a high voltage. You will significantly reduce the risk factor if you know and observe the follow- ing safety precautions: 1. Do not expose high voltage needlessly. Remove housings and covers only when necessary. Turn off equipment while making test connections in high-voltage circuits. Discharge high-voltage capacitors after removing power. 2. If possible, familiarize yourself with the equipment being tested and the location of its high volt- age points. However, remember that high voltage may appear at unexpected points in defective equipment. 3. Use an insulated floor material or a large, insulated floor mat to stand on, and an insulated work surface on which to place equipment. Make certain such surfaces are not damp or wet. 4. Use the time-proven "one hand in the pocket" technique while handling an instrument probe. Be particularly careful to avoid contacting a nearby metal object that could provide a good ground return path. 5. When testing AC powered equipment, remember that AC line voltage is usually present on some power input circuits, such as the on-off switch, fuses, power transformer etc., any time the equipment is connected to an AC outlet, even if the equipment is turned off.

CPR first aid is highly recommended.

This chapter explains the function of each control and connector on the 9412/9412A. Front Panel The front panel contains the most frequently used controls and connectors. Display The 9412/9412A features a backlit liquid crystal display, which displays menu selections and settings. The left half of the display shows the current menu selection, while the right half shows the current setting of the item associated with that menu. Control Buttons Toggles between the various items in a menu. Menu Button Toggles between the various sets of menus. Up Button Increments a number or increments the selection for the current item. Down Button Decrements a number or increments the selection for the current item.

For numeric items, this button is used to select which digit in a numeric entry is selected for editing. For other items or when the left most digit is already selected for numeric items, pressing and holding this button down displays a brief description of the current item. Right Button (range) For numeric items, this button is used to select which digit in a numeric entry is selected for editing. For other items or when the right most digit is already selected for numeric items, pressing and holding this button down displays the range and units for the current item. Stop Button Disables output of pulses on all channels. Run Button Enables output of pulses. Back Panel QC Connectors There are three (3) QC connectors on the rear of the 9412/9412A, 2 outputs and 1 input. T1 Channel 1 output -- a general-purpose pulse output, with programmable delay, pulse width, and pulse polarity. The maximum output voltage is adjustable and varies from 20 Volts open- circuit to 10 Volts when driving a 50 Ohm load. The maximum voltage is adjusted by a poten- tiometer located on the back of the 9412/9412A.

has all the capabilities of the other output channels, including several special modes which af- fect only the output of Channel 2. Ext/Gate External Trigger or Gate signal input -- used as either an external signal to trigger the genera- tion of pulses or as a gate signal to enable and disable the outputs. Output Voltage Adjustment The maximum output voltage of all output channels is adjusted by turning the potentiometer la- beled VOUT. Turn clockwise to increase the voltage, counter-clockwise to decrease the volt- age. The maximum voltage possible is 20 Volts into a high-impedance load or 10 Volts into a 50 Ohm load. Serial Port This is a 9-pin D-sub connector for the RS232 interface that comes standard with the 9412/9412A. It is pinned to be directly connected to a standard IBM-PC serial port -- use a straight-through cable (not a null modem cable) to connect to a PC. AC Input A standard IEC instrument-type cord should be used. The 9412/9412A is supplied with a power cord that fits the type of socket used in your country. Before plugging in, please make sure that the voltage selection switch is set to the proper setting for your country (either 110V or 220V). Line Voltage Selection This switch is used to select the voltage level used in your country -- make sure that it is on the proper setting or the 9412/9412A could be damaged.

Overview The 9412/9412A uses a single-line LCD to display menu selections. The front panel keys are used to "navigate" through sets of menus to set various options and control the pulse genera- tor. Some keys are only active at certain times or have different behavior depending on what state the menus are in -- once understood, the menus can be quickly and easily manipulated. The 9412/9412A also contains non-volatile memory for storing up to four (4) (eight (8) for the 9412A) configurations, so you need not go through the entire setup process each time the in- strument is used. Selecting Menu Items The menu items in the 9412/9412A are arranged in sets. Pressing the key will toggle be- tween sets of menus, while the key will toggle between menu items within the current set. Hold down the Left arrow key to receive a short description of the current menu item. Press- ing and holding the Right arrow key will display the valid range for that item. Numeric Input Mode When the current item is numeric, the system enters the Numeric Input mode. In this mode, the Left and Right arrow keys are used to select a digit to edit. The selected digit blinks to identify itself as the active digit. The Up and Down arrow keys are then used to increment or decrement this digit. When the left most digit is active, pressing and holding the Left arrow key will display a brief description of the current item. When the right most digit is active, pressing and holding the Right arrow key will display the range and units for the current item. Item Edit Mode When the current item is non-numeric, the Up and Down arrow keys are used to select among different options for the entry. The Left and Right arrow keys are used to display a description of the item.

riod and frequency of the 9412/9412A. MODE - Pulse Modes There are five (5) different Pulse modes available. Continuous Mode While in Continuous mode, the 9412/9412A will generate pulses at the rate set by the internal To Period as set in the ToPer menu. The delay of Channel 1 is relative to To, while the delay for Channel 2 is from the active edge of Channel 1. The Ext/Gate input may be used as a gate or interlock by setting the GATE menu to Low or High. Pulses will then only be generated while the Ext/Gate input is active. Selecting Low will make the gate active low, while selecting High will make the gate active high. Set to Off to disable the gate function. Note: No pulses are generated until the Run key has been pressed. External Trigger Mode In the External Trigger mode, one pulse is output each time an active edge occurs on the Ext/Gate input. The external trigger polarity menu (TRIG) is used to determine whether the 9412/9412A is triggered on the rising or falling edge of the external trigger. The delay of each output is relative to the active edge of the external trigger, except for Channel 2 which is delayed from the active edge of Channel 1. Since it is being used as a trigger source, the Ext/Gate input cannot be used as a gate in this mode. Single Shot Mode During Single Shot operation, one pulse is generated each time the Run key is pressed. The rate at which pulses are produced is totally dependent on how fast the Run key is pressed. The external trigger input may be used as a gate or interlock by setting the GATE menu to Low or High. Pulses will then only be generated while the external trigger input is active. Se- lecting Low will make the gate active low, while selecting High will make the gate active high.

output. The exception is the outputs are only active for a set number of seconds (DC:On menu), then disabled for another set time period (DC:Off menu) before being re-enabled. This cycle is repeated for a set number of times (CYCLES menu), after which all outputs cease. Setting the number of cycles to zero results in continuous cycling, until the Stop Key is pressed. The Ext/Gate input may be used as a gate or interlock by setting the GATE menu to Low or High. Pulses will then only be generated while the external trigger input is active. Selecting Low will make the gate active low, while selecting High will make the gate active high. The Run key must be pressed to start the Duty Cycle mode. Burst Burst mode is similar to Continuous, except only a certain number of pulses will be output (#/BURST menu), after which outputs are disabled. The Ext/Gate input may be used as a gate or interlock by setting the GATE menu to Low or High. Pulses will then only be generated while the external trigger input is active. Selecting Low will make the gate active low, while selecting High will make the gate active high. The Run key must be pressed to start Burst mode. GATE - Gate Select When not in External Trigger mode, the Ext/Gate input on the 9412/9412A can be used as a gate signal. When the gate is enabled, pulses will only be output while the signal into the Ext/Gate input is active -- thus, this signal will act as a safety interlock or external control sig- nal. The Ext/Gate input may be used as a gate or interlock by setting the GATE menu to Low or High. Pulses will then only be generated while the external trigger input is active. Selecting Low will make the gate active low, while selecting High will make the gate active high. Set- ting the GATE menu to Off will disable the Gate function. The setting of the GATE menu is used to determine when the signal is active. If the gate menu is set (active) High, pulses will only be generated if the Ext/Gate input signal is greater than 3.5 Volts. If set to (active) Low, outputs will be enabled as long as the Ext/Gate input signal is less than 2.0 Volts.

Except when in External Trigger or Single Shot mode, all pulse outputs are based on an inter- nal timer called To. This menu is used to select the rate at which To runs by selecting the time period in microseconds between timer pulses. When in Continuous, Burst, or Duty Cycle mode, pulses are output at the rate determined by To. The frequency of pulse outputs in these modes can be found by taking the reciprocal of the To Period setting. Width and Delay Menus This set of menus is used to set the delay and pulse width for each of the output channels. Note: Channel 2 delay is relative to the Channel 1 (T1) output. Tn:Dly - Tn Delay Each of the two channels has an independent delay setting which is set from the Tn:Dly, where n = 1 or 2. When in any mode but External Trigger, the Delay setting sets the delay from the time the in- ternal timer To goes high until a pulse is output on a particular channel. Note: In the case of Channel 2 (T2), the output is delayed from the active edge of T1 - not To as with the other channels. When in External Trigger mode, the delays are with respect to the active edge of the external trigger input signal. Tn:Wid - Tn Pulse Width Each of the two channels has an independent pulse width setting which is set from the Tn:Wid menu, where n = 1 or 2. The pulse width is used to specify the duration of the output pulse in µS. The setting of the output polarity (the Tn:Pol menu) for a particular channel determines whether the output is high for this duration or is low. Tn:Pol - Tn Polarity Each channel has an independent output polarity setting set from the Tn:Pol menu, where n = 1 or 2.

specified pulse width time, after which it will return to 0. The voltage level while high will de- pend upon the load and the setting of the output voltage adjustment on the back panel. If set to Negative, the output will normally be at the high voltage level. When the output is activated, it will go to 0 Volts for the specified pulse width time, after which it will return to the high level again. T2 Menus Channel 2 (T2) has some special features designed to be particularly useful when used as a Q-switch trigger. T2:Enable This menu is used to separately enable or disable the output of Channel 2, independent of the other channels. If set to On, Channel 2's output will be active under the same conditions as the other channels. When set to Off, Channel 2's output will remain disabled under all condi- tions. T2:Gate When not in External Trigger mode, the Ext/Gate input can be used to gate the output of all output channels or just the output of Channel 2. In order to use the input to gate Channel 2, the GATE selection in the Main Menu set must be set to Off and the T2:Gate selection must be set to Low or High. The setting of the T2:Gate menu is used to determine when the signal is active. If the gate menu is set (active) High, Channel 2 pulses will only be generated if the Ext/Gate input signal is greater than 3.5 Volts. If set to (active) Low, outputs will be enabled as long as the Ext/Gate input signal is less than 2.0 Volts.

number of pulses that must occur on the other channels before the output of Channel 2 is en- abled. This is particularly useful when using Channel 2 as a Q-switch trigger, as it allows the laser to thermally stabilize before activating the Q-switch. This function is active only in Continuous, Burst, and Duty Cycle modes. Channel 2 is delayed at the start of each burst in the Burst mode or at the start of each cycle in the Duty Cycle mode. T2*n - T2 Period Factor The period at which Channel 2 (T2) is pulsed can be set to be a multiple of the other channels. This menu item is used to select the multiplier. For example, if the To period ToPer) is set to .100 sec (10Hz), setting T2*n to 2 will cause the channel 2 period to be .200 sec (5Hz). Store/Recall/Misc. Menus The 9412/9412A contains non-volatile memory for storing four (4) (eight (8) for the 9412A) different configurations. The settings of all menu selections are stored and can be quickly re- called. STORE Configuration Stores the current menu settings in the specified memory location (one (1) - four (4) (eight (8) for 9412A). Note: If you overwrite a particular location, its previous contents are destroyed. To store a configuration use the Up and Down arrow keys to select the memory location number and press the Left or Right arrow key. You will be prompted to press the key to verify that you want to overwrite the existing stored configuration. If you press any other key, the configuration will not be saved.

configuration use the Up and Down arrow keys to select the memory location number and press the Left or Right arrow key. You will be prompted to press the key to verify that you want to overwrite the active configuration. If you press any other key, the configuration will not be recalled. Note: A zero configuration is available for recall. This configuration resets the instrument to the factory default settings. Shot Counter The 9412/9412A includes a nine (9) digit shot counter. The maximum count displayed is 4,294,967,295 after which the count rolls over to zero. To manually reset the counter to zero, press the Left or Right arrow key, at which time you will prompted to press the key to ver- ify that you want to zero the counter. If you press any other key, the shot counter will not be reset. Fmark The character used as a decimal point can be set to either a "." (period) or a "," (comma). The period is generally used in North America, while the comma is used in Europe. Volume The key click volume may be adjusted from 0 (disabled) to 9. The default value is 2.

and retrieved over the computer interface using a simple command language. Serial (RS232) Pinout The serial port is located on the back of the 9412/9412A and uses a 9-pin D-type connector with the following pinout (as viewed from the back of the 9412/9412A): 1. No connection 2. Tx - Transmit (to computer) 3. Rx - Receive (from computer) 4. DTR - connected to pin 6 5. Ground 6. DSR - connected to pin 4 7. RTS - connected to pin 8 8. CTS - connected to pin 7 9. No connection The voltage level of the Transmit signal is +/-10V, the Receive signal should be at least +/-5V. Command Language All menu items can be accessed and selected via the computer interface using a simple com- mand language. Command Protocol All commands have the following syntax: $ <##>CR where PP $ indicates a command follows. PP is the command name. No spaces are allowed between the $ and the . The name is case sensitive. PP <##> is an unsigned, integer associated with the command. A space must be inserted between and <##>.

With echo enabled, all characters sent will be echoed back to the sender. Unidentified commands and most out of range conditions result in the pulse generator ignoring the command. If the command is properly identified, the pulse generator returns an ok fol- lowed by a carriage return and a line feed (ASCII 13, ASCII 10), otherwise it returns a ?1 (a question mark, followed by the number "one", a carriage return and a line feed). A ?2 is sent if a valid command is received but the parameter is out of range. Example - send the following command to set the number of cycles: $CYCLES 100 The pulse generator will return the following: Echo Enabled: CYCLES 100 ok Echo Disabled: ok Only one command will be processed per message. Commands are not processed until the carriage return is sent. If an error is made and identified prior to sending the carriage return, sending a new $ will reset the input buffer and allow a corrected command to be sent. To determine the current value of a parameter the syntax is: $ ?CR where name = a valid command name. This will return an integer followed by a space, carriage return, and a line feed character (ASCII 10). Example - the following command would retrieve the current Cycles setting: $CYCLES ? The pulse generator will return the following: Echo Enabled: CYCLES ? 100 Echo Disabled: 100

establish RS232 communications, the pulse generator emits the characters QC approximately every 200 ms after power up and until the 9412/9412A receives a $.

Note: The name of each command is identical to how it appears on the display of the 9412/9412A.

Command Name Parameters Description MODE 0 = Continuous mode 1 = Burst mode 2 = Duty Cycle mode 3 = Single Shot mode 4 = External Trigger mode Sets the pulse generator mode. GATE 0 = off 1 = active low 2 = active high Enables the external trigger input to function as a gate controlling all outputs. Cannot be used with external trigger mode. ToPer 1000 - 99999999 µs 500 - 99999999 µs (400B) Sets the To internal sync period, used only in Continu- ous, Burst and Duty Cycle modes. DC:On 1 - 10000 Sec Sets the on time, in seconds, for the Duty Cycle mode. DC:Off 1 - 10000 Sec Sets the off time, in seconds, for the Duty Cycle mode. TRIG 0 = falling edge 1 = rising edge Sets the active edge of the Ext/Gate signal when used as an external trigger. CYCLES 0 - 10000 cycles Sets the number of cycles for the Duty Cycle mode. #/BURST 1 - 50000 pulses Sets the number pulses in the Burst mode. T1:Wid 1 - 99999999 µs Sets the pulse width, in microseconds, for Channel 1. T1:Dly 0 - 99999999 µs Sets the delay, in microseconds, for Channel 1. T1:Pol 0 = Negative (active low) 1 = Positive (active high) Sets the polarity of the output for Channel 1. T2:Wid 1 - 99999999 µs Sets the pulse width, in microseconds, for Channel 2. T2:Dly 0 - 99999999 µs Sets the delay, in microseconds, for Channel 2. Note: The delay is relative to Channel 1. T2:Pol 0 = Negative (active low) 1 = Positive (active high) Sets the polarity of the output for Channel 2. T2:Enable 0 = Off 1 = On Turns the output of Channel 2 on and off. T2:Gate 0 = Off 1 = Active low 2 = Active high Enables the external input to act as a gate for Channel 2's output. T2:Wait 0 - 10000 pulses Set the number of pulses to wait after starting T1 before enabling T2. Note: This is used to allow time for the la- ser to stabilize when T1 is used as a flashlamp trigger and T2 is the Q-switch trigger. T2*n 1 - 10000 Sets the period of T2 relative to T1. The period of T2 is the period of T1 multiplied by n. BEEP 1 - 1000 Beeps the buzzer inside the 9412/9412A the specified number of times. RUN 0 = Disable 1 = Enable Enable / disables the pulse generator output.

RECALL 0 - 4 (9412) 0 - 8 (9412A) Recall a stored configuration. STORE 1 - 4 (9412) 1 - 8 (9412A) Store a configuration. SHOTS (9412A Only) 0 = Reset to zero Resets shot counter. SHOT ? will return the number of shots. ECHO 0 = Disable 1 = Enable Enables/Disables the RS232 echo. The result string is always sent back. Fmark, 0 = , (comma) 1 = . (period) Sets the character used as a decimal point on the display. VOLUME 0 - 9 Sets the key click volume level.

P DELAY 0 to 99.999999 sec P PULSEWIDTH 10 µs to 99.999999 sec P RESOLUTION 1 µs P ACCURACY 100 ns + .0002 x delay P TIMEBASE 8 MHz, 50 PPM crystal oscillator P RMS JITTER 50 ns + .0002 x period, 200 ns max P TRIG DELAY Ext Trig to To < 100 ms EXTERNAL TRIG / GATE P RATE Dc to 1/ (100 µs + largest delay + period) P THRESHOLD 3 VDc (3 mA into optoisolator) P TRIGGER SLOPE Rising or falling edge P GATE Active low or active high P IMPEDANCE 1000 Ω INTERNAL RATE GENERATOR P MODES Single shot, burst, duty cycle, continuous, external trigger, exter- nal gate P RATE (To period) 1000 µs to 99.999999 sec (.01 Hz to 1 KHz) (400A) 500 µs to 99.999999 sec (.01 Hz to 2 KHz) (400B) P ACCURACY 100 ns + .0002 x period P RMS JITTER 50 ns + .0002 x period BURST MODE 1 to 50,000 pulses

P OVERSHOOT < 100 mV + 10% of pulse amplitude P AMPLITUDE 1-10V into 50Ω load 2-20V into high impedance load manually adjusted, all outputs at same level P PEAK CURRENT 400 mA per channel P AVERAGE CURRENT 200 mA average (total for all channels) COMPUTER INTERFACE P RS232 9600 Baud. All instrument functions and settings may be con- trolled over the interface bus. GENERAL P STORAGE Four (4) complete configurations (8 - 9412A), may be stored and recalled from the front panel or the computer interface. P DIMENSIONS 7.5" x 9.0" x 4.0" P WEIGHT 5 lbs.

Replacing the Fuse The fuse is mounted on the circuit board located inside the 9412/9412A. Remove the top cover to access and follow the instructions given below to replace the fuse: 1. Unplug the 9412/9412A from power source and remove power cord from the back panel. 2. Remove the two screws located on the sides of the 9412/9412A (they hold the front plastic bezel in place) and remove bezel. 3. Remove the two screws located on the sides of the 9412/9412A (they hold the back plastic bezel in place) and remove the bezel. 4. Lift the top cover to remove. 5. Locate the fuse on the circuit board (small glass cylinder located in the right rear corner) at- tached to the circuit board by metal spring clips. 6. Remove faulty fuse and replace with one of a similar rating (5 x 20 mm, .125 Amp). 7. Replace top cover and bezels. 8. Reattach the power cord.