INSTRUCTIONS MODEL AVR-G1-C-PN-MITC1-OP1 PULSE GENERATOR S.N.: __________________________________________________________________ WARRANTY Avtech Electrosystems Ltd. warrants products of its manufacture to be f ree from defects in material and workmanship under conditions of normal use. If, within one year after delivery to the original owner, and after prepaid return by the origina l owner, this Avtech product is found to be defective, Avtech shall at its option repair or replace said defective item. This warranty does not apply to units which have been dissembled, modified or subjected to conditions exceeding the applicable specificat ions or ratings. This warranty is the extent of the obligation assumed by Avtech with re spect to this product and no other warranty or guarantee is either expressed or impli ed. TECHNICAL SUPPORT Phone: 613-226-5772 or 1-800-265-6681 Fax: 613-226-2802 or 1-800-561-1970 E-mail: info@avtechpulse.com World Wide Web: http://www.avtechpulse.com __________________________________________________________________ TABLE OF CONTENTS WARRANTY............................................................... ............................................. TECHNICAL SUPPORT...................................................... .................................... FIG. 1 PULSE GENERATOR TEST ARRANGEMENT............................... ........... GENERAL OPERATING INSTRUCTIONS......................................... .................... FIG. 2 FRONT PANEL CONTROLS........................................... ........................... FIG. 3 BACK PANEL CONTROLS............................................ ............................. TOP COVER REMOVAL AND RACK MOUNTING.................................... ............. SYSTEM DESCRIPTION AND REPAIR PROCEDURE................................ ......... PERFORMANCE CHECK SHEET................................................ .......................... QUOTATION, SPECIFICATIONS.............................................. ............................. OP1 OPERATING INSTRUCTIONS (AN-102-AVR-G1)............................. ............ __________________________________________________________________ F IG. 1 PULSE GENERATOR TEST ARRANGEM E NT __________________________________________________________________ GENERAL OPERATING INSTRUCTIONS 1) For front panel manual control of the output parameters, the rear panel LOCAL-REMOTE switch must be in the LOCAL position. For remote control using a personal computer, the switch should be in the REMOTE position. See the AN-102-AVR-G1 section (at the end of the manual) for the instructio ns for this mode of operation. It is strongly recommended that the manual ope ration of the instrument be mastered before attempting the computer control opera tion. 2) The bandwidth capability of components and instruments used to display the pulse generator output signal (attenuators, cables, connectors, et c.) should exceed 100 MHz. Note that this unit is designed to operate into a high impedance (> 10K) and may fail if operated into 50 Ohms. 3) The TRIG output channel provides TTL level signals. To avoid overdriv ing the TRIG input channel of some scopes, a 30 dB attenuator should be placed at the input to the scope trigger channel. The TRIG output precedes the main output when the front panel ADVANCE-DELAY switch is in the ADVANCE position. The TRIG output lags the main output when the switch is in the DELAY po sition. The DELAY control controls the relative delay between the re ference output pulse provided at the TRIG output and the main output. This delay is variable over the range of 0.1 us to 100 us: MIN MAX Range 1 0.1 us 1.0 us Range 2 1.0 us 10 us Range 3 10 us 100 us __________________________________________________________________ 4) The output pulse width is controlled by means of the front panel one t urn PW control and by the PW RANGE control (units with -PWT option have a ten turn PW control). Note that the MODE A-B switch must be in the A position . The minimum and maximum PW for each range and the corresponding maximum PRF are as follows. Note that the unit may fail if operated at duty c ycles exceeding 20%: PW min PW max Range 1 0.1 us 1.0 us PRF max 1 kHz PRF max 1 kHz Range 2 1.0 us 10 us PRF max 1 kHz PRF max 1 kHz Range 3 10 us 100 us PRF max 1 kHz PRF max 1 kHz 5) To obtain a stable output display the PRF control on the front panel sh ould be set mid range. The front panel INT-EXT toggle switch should be in the INT position and the MODE A-B switch should be in the A position. The DELA Y controls and the scope triggering controls are then adjusted to obtain a stable output. The scope may then be used to set the desired PRF by rotating the PRF and PRF FINE controls. 6) The output pulse amplitude is controlled by means of the two front pane l ten turn AMP controls. 7) An external clock may be used to control the output PRF of the AVR uni t by setting the front panel INT-EXT toggle switch in the EXT position and a pplying a 50 ns (or wider) TTL level pulse to the TRIG BNC connector input. Wit h the MODE A-B switch in the A position, the output pulse width will be contr olled by the front panel PW controls. If the switch is in the B position, the o utput pulse width equals the input trigger pulse width. 8) For single pulse manual operation, set the front panel INT-EXT-MAN swit ch in the MAN position and push the SINGLE PULSE button. __________________________________________________________________ 9) CAUTION: The output stage is protected against overload condition by a 0.25A slow blow fuse on the main frame back panel. However, the output switc hing elements may fail if the unit is triggered at a PRF exceeding 1 kHz or at duty cycles exceeding 20%. Heating and subsequent likely failure of the o utput stage is reduced if the following action is taken where possible: a) PRF is kept to a minimum, i.e. operate in a low PRF range when poss ible rather than in a high PRF range b) Keep the output PW to a minimum. 10) OVERLOAD INDICATOR. AVR-G-C units with a serial number higher than 5600 are protected by an automatic overload protective circuit which c ontrols the front panel overload light. If the unit is overloaded (by operati ng at an exceedingly high duty cycle or by operating into a short circuit), the protective circuit will turn the output of the instrument OFF and turn the indicat or light ON. The light will stay ON (i.e. output OFF) for about 5 seconds after whic h the instrument will attempt to turn ON (i.e. light OFF) for about 1 second. If the overload condition persists, the instrument will turn OFF again (i.e. light ON) for another 5 seconds. If the overload condition has been removed, the ins trument will turn on and resume normal operation. Overload conditions may be removed by: 1) Reducing PRF (i.e. switch to a lower range) 2) Reducing pulse width (i.e. switch to a lower range) 3) Removing output load short circuit (if any) 11) The unit can be converted from 110 to 220V 50-60 Hz operation by adjus ting the voltage selector card in the rear panel fused voltage selector cab le connector assembly. 12) For further assistance: Tel: 613-226-5772 Fax: 613-226-2802 __________________________________________________________________ FIG. 2 FRONT PANEL CONTROLS __________________________________________________________________ (1) ON-OFF Switch. Applies basic prime power to all stages. (2) PRF Control. Varies PRF from 1.0 Hz to 1.0 kHz as follows: Range 1 1 Hz to 10 Hz Range 2 10 Hz to 100 Hz Range 3 100 Hz to 1 kHz (3) DELAY Control. Controls the relative delay between the reference outp ut pulse provided at the TRIG output (4) and the main output (5). This delay i s variable over the range of 0.1 to about 1 ms. Delay LEADS or LAGS depending on the position of the ADVANCE-DELAY switch. MIN MAX Range 1 0.1 us 1.0 us Range 2 1.0 us 10 us Range 3 10 us 100 us (4) TRIG Output. This output is used to trigger the scope time base. The output is a TTL level 100 ns (approx.) pulse capable of driving a fifty Ohm load . This output precedes the output at (5) if the two-position ADVANCE-DELAY sw itch is in the ADVANCE position. This output follows the output at (5) if the switch is in the DELAY position. The delay range is variable from 0.1 us to 100 us. The external trigger signal is applied at this input when the EXT-INT togg le switch is in the EXT position. (5) OUT Connectors. BNC connectors provide outputs to 10K (or higher) load s. __________________________________________________________________ (6) PW Control. A one turn control (ten turn control for units with the -P WT option) and 4-position range switch which varies the positive output pulse wid th from 0.1 us to 1 ms (when the MODE A-B switch is in the A position). The minim um and maximum PW for each range and the corresponding maximum PRF are as follows. Note that the unit may fail if operated at duty cycles exce eding the above. PW min PW max Range 1 0.1 us 1.0 us PRF max 1 kHz PRF max 1 kHz Range 2 1.0 us 10 us PRF max 1 kHz PRF max 1 kHz Range 3 10 us 100 us PRF max 1 kHz PRF max 1 kHz (7) AMP Controls. Two ten turn controls which varies the output pulse ampl itudes (POS and NEG). (8) EXT-INT-MAN Control. With this toggle switch in the INT position, the PRF of the AVR unit is controlled via an internal clock which in turn is contr olled by the PRF control. With the toggle switch in the EXT position, the AVR unit requires a 50 ns (or wider) TTL level pulse applied at the TRIG input in order to trigger the output stages. In addition, in this mode, the scope time base must be triggered by the external trigger source. With the MODE A-B switch in the A posi tion the output pulse width is controlled by the PW controls. With the MODE A-B switch in the B position, the output pulse width equals the input trigger puls e width. For single pulse operation, set the INT-EXT-MAN switch in the MAN position. (9) SINGLE PULSE. For single pulse manual operation, set the front panel INT- EXT-MAN switch in the MAN position and push the SINGLE PULSE button. (10) MODE A-B. For output pulse width control via the PW controls, the MOD E switch should be in the A position. When triggering via an externally applied TTL level trigger pulse, the output pulse width equals the input trigger pulse width if the MODE switch is in the B position. __________________________________________________________________ (11) OVERLOAD INDICATOR. AVR units with a serial number higher than 5600 a re protected by an automatic overload protective circuit which controls t he front panel overload light. If the unit is overloaded (by operating at an ex ceedingly high duty cycle or by operating into a short circuit), the protective circuit will turn the output of the instrument OFF and turn the indicator light ON. The light will stay ON (i.e. output OFF) for about 5 seconds after which the instrumen t will attempt to turn ON (i.e. light OFF) for about 1 second. If the overloa d condition persists, the instrument will turn OFF again (i.e. light ON) for anoth er 5 seconds. If the overload condition has been removed, the instrument will turn on and resume normal operation. Overload conditions may be removed by: 1) Reducing PRF (i.e. switch to a lower range) 2) Reducing pulse width (i.e. switch to a lower range) 3) Removing output load short circuit (if any) __________________________________________________________________ FIG. 3 BACK PANEL CONTROLS __________________________________________________________________ (1) FUSED CONNECTOR, VOLTAGE SELECTOR. The detachable power cord is connected at this point. In addition, the removable cord is adjusted t o select the desired output operating voltage. The unit also contains the main powe r fuse (0.5A SB) (2) 0.25A SB. Fuse which protects the output stage if the output duty cycl e rating is exceeded. (3) LOCAL REMOTE SWITCH. This two-position switch must be in the LOCAL position to operate the instrument from the front panel controls. To c ontrol the instrument using your personal computer, the switch must be in the REMO TE position. (4) OP1 CONNECTOR. GPIB cable (supplied) connects between this connector and your personal computer. __________________________________________________________________ TOP COVER REMOVAL AND RACK MOUNTING 1) The interior of the instrument may be accessed by removing the four Phi llips screws on the top panel. With the four screws removed, the top cover m ay be slid back (and off). 2) The -R rack mount kit may be installed after first removing the one Phillips screw on the side panel adjacent to the front handle. __________________________________________________________________ SYSTEM DESCRIPTION AND REPAIR PROCEDURE The AVR-G1-C consists of the following basic modules: 1) AVR-G1-PG pulse generator module 2) AVR-G1-CL clock module 3) +24V power supply board 4) AVR-G1-PS power supply module 5) AVR-G1-PW pulse width module 6) AVR-OL overload module The modules are interconnected as shown in Fig. 4. The clock module co ntrols the output PRF and the relative delay between the main output and the S YNC outputs. The PG pulse generator modules generate the output pulse. Th e PS module generates 0 to ±200 Volts to power the pulse generator module. The PW module controls the output pulse width. In the event of an instrume nt malfunction, it is most likely that the rear panel 0.25A SB fuse or som e of the output switching elements (SL4T) may have failed due to an output short circuit condition or to a high duty cycle condition. The switching elements ma y be accessed by removing the cover plate on the bottom side of the instrume nt. NOTE: First turn off the prime power. CAUTION: Briefly ground the S L4T tabs to discharge the 200 Volts power supply potential. The elements may b e removed from their sockets by means of a needle nosed pliers. The SL4T is a selected MOSFET power transistor in a TO 220 package and may be checked on a curve tracer. If defective, replacement units should be ordered directly from Avtech. When replacing the SL4T switching elements, take care to insure that the short lead (of the three leads) is adjacent to the back of the chassis. If the switching elements are not defective, then the four Phillips screw s on the back panel should be removed. The top cover may then be slid off and operation of the clock and power supply modules should be checked. The clock module is functioning properly if: a) 0.1 us TTL level outputs are observed at pins 2 and 3. b) The PRF of the outputs can be varied over the range of 1 Hz to 1 kHz using the PRF controls. c) The relative delay between the pin 2 and 3 outputs can be varied by at least 0.1 us to 1.0 us by the DELAY controls. __________________________________________________________________ __________________________________________________________________ PERFORMANCE CHECK SHEET __________________________________________________________________ QUOTATION, SPECIFICATIONS __________________________________________________________________ __________________________________________________________________ OP1 OPERATING INSTRUCTIONS (AN-102-AVR-G1) __________________________________________________________________ Document Outline * [1]WARRANTY * [2]TECHNICAL SUPPORT * [3]FIG. 1 PULSE GENERATOR TEST ARRANGEMENT * [4]GENERAL OPERATING INSTRUCTIONS * [5]FIG. 2 FRONT PANEL CONTROLS * [6]FIG. 3 BACK PANEL CONTROLS * * [7]TOP COVER REMOVAL AND RACK MOUNTING * [8]SYSTEM DESCRIPTION AND REPAIR PROCEDURE * [9]PERFORMANCE CHECK SHEET * [10]QUOTATION, SPECIFICATIONS * [11]OP1 OPERATING INSTRUCTIONS (AN-102-AVR-G1) __________________________________________________________________ References Visible links: 1. file:///root/tmp.html#2 2. file:///root/tmp.html#2 3. file:///root/tmp.html#4 4. file:///root/tmp.html#5 5. file:///root/tmp.html#8 6. file:///root/tmp.html#12 7. file:///root/tmp.html#14 8. file:///root/tmp.html#15 9. file:///root/tmp.html#17 10. file:///root/tmp.html#18 11. file:///root/tmp.html#20 Hidden links: 13. file://localhost/root/tmp.html#13