Avtech AVR-A-1-S2-C User manual

INSTRUCTIONS
MODEL AVR-A-1-S2-C
0 TO 200 VOLTS, 2 ns RISE TIME
HIGH PERFORMANCE PULSE GENERATOR
WITH IEEE 488.2 AND RS-232 CONTROL
SERIAL NUM ER: ____________
A V T E C H E L E C T R O S Y S T E M S L T D .
N A N O S E C O N D W A V E F O R M E L E C T R O N I C S
S I N C E 1 9 7 5
P.O. OX 265
OGDENS URG, NY
U.S.A. 13669-0265
TEL: [phone] (USA & Canada) or [phone] (Intl)
FAX: [phone] (USA & Canada) or [phone] (Intl)
[e-mail] - http://www.avtechpulse.com/
X
OX 5120, LCD MERIVALE
OTTAWA, ONTARIO
CANADA K2C 3H4

WARRANTY
Avtech Electrosystems Ltd. warrants products of its manufacture to be free
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 original 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 specifications or ratings. This warranty is the extent of
the obligation assumed by Avtech with respect to this product and no other
warranty or guarantee is either expressed or implied.
TECHNICAL SUPPORT
Phone: [phone] (USA & Canada) or [phone] (Intl)
Fax: [phone] (USA & Canada) or [phone] (Intl)
E-mail: [e-mail]
World Wide Web: http://www.avtechpulse.com
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TA LE OF CONTENTS
WARRANTY......................................................................................................................2
TECHNICAL SUPPORT...................................................................................................2
TABLE OF CONTENTS....................................................................................................3
INTRODUCTION...............................................................................................................5
AVAILABLE OPTIONS............................................................................................................5
HIGH-VOLTAGE PRECAUTIONS....................................................................................6
SPECIFICATIONS............................................................................................................7
EUROPEAN REGULATORY NOTES..............................................................................8
EC DECLARATION OF CONFORMITY..................................................................................8
DIRECTIVE 2002/95/EC (RoHS).............................................................................................8
DIRECTIVE 2002/96/EC (WEEE)............................................................................................8
INSTALLATION..............................................................................................................10
VIS AL CHECK....................................................................................................................10
POWER RATINGS................................................................................................................10
CONNECTION TO THE POWER S PPLY...........................................................................10
PROTECTION FROM ELECTRIC SHOCK...........................................................................11
ENVIRONMENTAL CONDITIONS.........................................................................................11
FUSES.............................................................................................................................13
AC F SE REPLACEMENT...................................................................................................13
DC F SE REPLACEMENT...................................................................................................14
F SE RATINGS....................................................................................................................14
FRONT PANEL CONTROLS..........................................................................................15
REAR PANEL CONTROLS............................................................................................17
GENERAL INFOR ATION.............................................................................................18
BASIC TEST ARRANGEMENT.............................................................................................18
BASIC P LSE CONTROL....................................................................................................18
AMPLIT DE DYNAMIC RANGE...........................................................................................19
INI IZING WAVEFOR DISTORTIONS....................................................................21
SE 50Ω TRANSMISSION LINES AND LOADS..................................................................21
SE LOW-IND CTANCE LOADS........................................................................................21
PREVENTING DA AGE................................................................................................21
ECHANICAL INFOR ATION......................................................................................22
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TOP COVER REMOVAL.......................................................................................................22
RACK MO NTING................................................................................................................22
ELECTROMAGNETIC INTERFERENCE..............................................................................22
AINTENANCE..............................................................................................................23
REG LAR MAINTENANCE..................................................................................................23
CLEANING............................................................................................................................23
WIRING DIAGRA S.......................................................................................................24
WIRING OF AC POWER.......................................................................................................24
PCB 158M - LOW VOLTAGE POWER S PPLY, 1/3...........................................................25
PCB 158M - LOW VOLTAGE POWER S PPLY, 2/3...........................................................26
PCB 158M - LOW VOLTAGE POWER S PPLY, 3/3...........................................................27
PCB 168B - HIGH-VOLTAGE POWER S PPLY..................................................................28
PCB 126C - OSCILLATOR....................................................................................................29
MAIN WIRING.......................................................................................................................30
PERFOR ANCE CHECKSHEET..................................................................................31
Manual Reference: Z:\officefiles\instructword\avr-a-1\AVR-A-1-S2-C,ed2.odt.
Last modified August 19, 2008.
Copyright © 2008 Avtech Electrosystems Ltd, All Rights Reserved.
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INTRODUCTION
The AVR-A-1-S2-C is a high performance, GPI and RS232-equipped instrument
capable of generating 200V into 50Ω loads at repetition rates up to 10 kHz. The output
pulse width is variable from 10 to 200 ns, and the sync delay is variable up to ±200 ns.
The rise time is fixed at less than 2 ns.
Instruments with the "-P" model suffix can generate 0 to +200V, whereas instruments
with the "-N" model suffix can generate 0 to -200V. Instruments with the "-PN" suffix can
generate both polarities.
The AVR-A-1-S2-C is a highly flexible instrument. Aside from the internal trigger source,
it can also be triggered or gated by external TTL-level signals. A front-panel pushbutton
or a computer command can also be used to trigger the instrument.
The AVR-A-1-S2-C features front panel keyboard and adjust knob control of the output
pulse parameters along with a four line by 40 character back-lit LCD display of the
output amplitude, pulse width, pulse repetition frequency, and delay. The instrument
includes memory to store up to four complete instrument setups. The operator may use
the front panel or the computer interface to store a complete “snapshot” of all key
instrument settings, and recall this setup at a later time.
This instrument is intended for use in research, development, test and calibration
laboratories by qualified personnel.
AVAILA LE OPTIONS
The AVR-A-1-S2-C is available with several options:
-OS Option: an externally generated DC offset can be added to the output.
-EA Option: the amplitude can be controlled by an externally generated 0 to +10V
analog control voltage.
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HIGH-VOLTAGE PRECAUTIONS
CA TION: This instrument provides output voltages as high as 200 Volts under
normal operating conditions, and generates > 230V internally, so extreme caution must
be employed when using this instrument. The instrument should only be used by
individuals who are thoroughly skilled in high voltage laboratory techniques. The
following precautions should always be observed:
1. Keep exposed high-voltage wiring to an absolute minimum.
2. Wherever possible, use shielded connectors and cabling.
3. Connect and disconnect loads and cables only when the amplifier is turned off.
4. Keep in mind that all cables, connectors, oscilloscope probes, and loads must have
an appropriate voltage rating.
Do not attempt any repairs on the instrument, beyond the fuse replacement procedures
described in this manual. Contact Avtech technical support (see page 2 for contact
information) if the instrument requires servicing.
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SPECIFICATIONS
Model: AVR-A-1-S2-C1
Amplitude3,4,5: (50 Ohm load) 0 to 200 Volts
Pulse width3,5: 10 ns to 200 ns
PRF: 0 to 10 kHz
Rise and fall time: ≤ 2 ns
Maximum duty cycle: 0.2%
Maximum avg. output power: 1.6 Watts
Polarity6: Positive or negative or both (specify)
Front-panel controls: Decade range switches & one-turn dials for PRF, pulse width & delay; one-turn dial for
amplitude.
Propagation delay: 30 ns (Ext trig in to pulse out)
Jitter: ± 100 ps ± 0.03% of sync delay, Ext trig in to pulse out
DC offset or bias insertion: Option available. Apply required DC offset or bias in the range of ± 50 Volts,
(250 mA max) to back panel solder terminal. See note 7.
Trigger required: External trigger mode: +5 Volts, 50 ns to 5 us (TTL)
Variable sync delay: 0 to ± 200 ns (Sync out to pulse out)
Sync output: +3 Volts, 200 ns, will drive 50 Ohm loads
Connectors: Out, Trig / Sync: NC
Dimensions (H x W x D): 100 mm x 430 mm x 375 mm (3.9” x 17” x 14.8”)
Power requirements: 100 - 240 Volts, 50 - 60 Hz
Chassis material: Cast aluminum frame & handles, blue vinyl on aluminum cover plates
Mounting: Any
Temperature range: +5°C to +40°C
1) -C suffix indicates stand-alone lab instrument with internal clock and line powering. No suffix indicates miniature module requiring DC power and
external trigger. (See http://www.avtechpulse.com/formats for details of the four basic instrument formats).
2) - suffix indicates IEEE-488.2 GPI and RS-232 control of amplitude, pulse width, PRF and delay (See http://www.avtechpulse.com/gpib).
3) For analog electronic control (0 to +10V) of the amplitude, suffix model number with -EA. Electronic control units also include standard front-panel
controls.
4) For operation at amplitudes of less than 20% of full-scale, best results will be obtained by setting the amplitude near full-scale and using external
attenuators on the output.
5) For 10-turn dial control of pulse width (or amplitude) suffix model number with -PWT (or -AT). For -C units only.
6) Indicate desired polarity by suffixing model No. by -P or -N (i.e. positive or negative) or -PN for dual polarity option. Polarity reversal is achieved by
means of a two-position switch on -C units and by keypad control on - units.
7) For DC offset option suffix model number with -OS.
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EUROPEAN REGULATORY NOTES
EC DECLARATION OF CONFORMITY
We Avtech Electrosystems Ltd.
P.O. ox 5120, LCD Merivale
Ottawa, Ontario
Canada K2C 3H4
declare that this pulse generator meets the intent of Directive 89/336/EEC for
Electromagnetic Compatibility. Compliance pertains to the following specifications as
listed in the official Journal of the European Communities:
EN 50081-1 Emission
EN 50082-1 Immunity
and that this pulse generator meets the intent of the Low Voltage Directive 72/23/EEC
as amended by 93/68/EEC. Compliance pertains to the following specifications as listed
in the official Journal of the European Communities:
EN 61010-1:2001 Safety requirements for electrical equipment for
measurement, control, and laboratory use
DIRECTIVE 2002/95/EC (RoHS)
This instrument is exempt from Directive 2002/95/EC of the European Parliament and
of the Council of 27 January 2003 on the Restriction of the use of certain Hazardous
Substances (RoHS) in electrical and electronic equipment. Specifically, Avtech
instruments are considered "Monitoring and control instruments" (Category 9) as
defined in Annex 1A of Directive 2002/96/EC. The Directive 2002/95/EC only applies to
Directive 2002/96/EC categories 1-7 and 10, as stated in the "Article 2 - Scope" section
of Directive 2002/95/EC.
DIRECTIVE 2002/96/EC (WEEE)
European customers who have purchased this equipment directly from Avtech will have
completed a “WEEE Responsibility Agreement” form, accepting responsibility for
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WEEE compliance (as mandated in Directive 2002/96/EC of the European Union and
local laws) on behalf of the customer, as provided for under Article 9 of Directive
2002/96/EC.
Customers who have purchased Avtech equipment through local representatives
should consult with the representative to determine who has responsibility for WEEE
compliance. Normally, such responsibilities with lie with the representative, unless other
arrangements (under Article 9) have been made.
Requirements for WEEE compliance may include registration of products with local
governments, reporting of recycling activities to local governments, and financing of
recycling activities.
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INSTALLATION
VISUAL CHECK
After unpacking the instrument mainframe and the transformer module, examine to
ensure that they have not been damaged in shipment. Visually inspect all connectors,
knobs, and handles. Confirm that a power cord and an instrumentation manual (this
manual), are with the instrument. If the instrument has been damaged, file a claim
immediately with the company that transported the instrument.
POWER RATINGS
This instrument is intended to operate from 100 - 240 V, 50 - 60 Hz.
The maximum power consumption is 57 Watts. Please see the “FUSES” section for
information about the appropriate AC and DC fuses.
This instrument is an “Installation Category II” instrument, intended for operation from a
normal single-phase supply.
CONNECTION TO THE POWER SUPPLY
An IEC-320 three-pronged recessed male socket is provided on the back panel for AC
power connection to the instrument. One end of the detachable power cord that is
supplied with the instrument plugs into this socket. The other end of the detachable
power cord plugs into the local mains supply. Use only the cable supplied with the
instrument. The mains supply must be earthed, and the cord used to connect the
instrument to the mains supply must provide an earth connection. (The supplied cord
does this.)
Warning: Failure to use a grounded outlet may result in injury or death due to
electric shock. This product uses a power cord with a ground connection. It must be
connected to a properly grounded outlet. The instrument chassis is connected to the
ground wire in the power cord.
The table below describes the power cord that is normally supplied with this instrument,
depending on the destination region:
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Destination Region Description Manufacturer Part Number
Continental Europe European CEE 7/7
“Schuko” 230V, 50Hz Qualtek (http://www.qualtekusa.com) 319004-T01
United Kingdom S 1363,
230V, 50Hz Qualtek (http://www.qualtekusa.com) 370001-E01
Switzerland SEV 1011, 2
30V, 50Hz Volex (http://www.volex.com) 2102H-C3-10
Israel SI 32,
220V, 50Hz Volex (http://www.volex.com) 2115H-C3-10
North America,
and all other areas
NEMA 5-15,
120V, 60 Hz Qualtek (http://www.qualtekusa.com) 312007-01
PROTECTION FROM ELECTRIC SHOCK
Operators of this instrument must be protected from electric shock at all times. The
owner must ensure that operators are prevented access and/or are insulated from
every connection point. In some cases, connections must be exposed to potential
human contact. Operators must be trained to protect themselves from the risk of
electric shock. This instrument is intended for use by qualified personnel who recognize
shock hazards and are familiar with safety precautions required to avoid possibly injury.
In particular, operators should:
1. Keep exposed high-voltage wiring to an absolute minimum.
2. Wherever possible, use shielded connectors and cabling.
3. Connect and disconnect loads and cables only when the instrument is turned off.
4. Keep in mind that all cables, connectors, oscilloscope probes, and loads must
have an appropriate voltage rating.
5. Do not attempt any repairs on the instrument, beyond the fuse replacement
procedures described in this manual. Contact Avtech technical support (see
page 2 for contact information) if the instrument requires servicing. Service is to
be performed solely by qualified service personnel.
ENVIRONMENTAL CONDITIONS
This instrument is intended for use under the following conditions:
1. indoor use;
2. altitude up to 2 000 m;
3. temperature 5 °C to 40 °C;
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4. maximum relative humidity 80 % for temperatures up to 31 °C decreasing
linearly to 50 % relative humidity at 40 °C;
5. Mains supply voltage fluctuations up to ±10 % of the nominal voltage;
6. no pollution or only dry, non-conductive pollution.
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FUSES
This instrument contains four fuses. All are accessible from the rear-panel. Two protect
the AC prime power input, and two protect the internal DC power supplies. The
locations of the fuses on the rear panel are shown in the figure below:
AC FUSE REPLACEMENT
To physically access the AC fuses, the power cord must be detached from the rear
panel of the instrument. The fuse drawer may then be extracted using a small flat-head
screwdriver, as shown below:
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Fuses #1 and #2
(AC fuses)
Fuse #4
(DC fuse)
Fuse #3
(DC fuse)
Fuse
Drawer
Pry out the fuse
drawer using a
screwdriver.

DC FUSE REPLACEMENT
The DC fuses may be replaced by inserting the tip of a flat-head screwdriver into the
fuse holder slot, and rotating the slot counter-clockwise. The fuse and its carrier will
then pop out.
FUSE RATINGS
The following table lists the required fuses:
Fuses
Nominal
Mains
Voltage
Rating Case Size
Recommended Replacement Part
Littelfuse Part
Number
Digi-Key Stock
Number
#1, #2 (AC) 100-240V 0.5A, 250V,
Time-Delay 5×20 mm 0218.500HXP F2416-ND
#3 (DC) N/A 1.0A, 250V,
Time-Delay 5×20 mm 0218001.HXP F2419-ND
#4 (DC) N/A 0.5A, 250V,
Time-Delay 5×20 mm 0218.500HXP F2416-ND
The recommended fuse manufacturer is Littelfuse (http://www.littelfuse.com).
Replacement fuses may be easily obtained from Digi-Key (http://www.digikey.com) and
other distributors.
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FRONT PANEL CONTROLS
1) POWER Switch . This is the main power switch. When turning the instrument on,
there may be a delay of several seconds before the instrument appears to respond.
2) OVERLOAD Indicator . When the instrument is powered, this indicator is normally
green, indicating normal operation. If this indicator is yellow, an internal automatic
overload protection circuit has been tripped. If the unit is overloaded (by operating
at an exceedingly high duty cycle or by operating into a very low impedance), the
protective circuit will disable the output of the instrument and turn the indicator light
yellow. The light will stay yellow (i.e. output disabled) for about 5 seconds after
which the instrument will attempt to re-enable the output (i.e. light green) for about
1 second. If the overload condition persists, the output will be disabled again (i.e.
light yellow) for another 5 seconds. If the overload condition has been removed, the
instrument will resume normal operation.
This overload indicator may flash yellow briefly at start-up. This is not a cause for
concern.
3) PRF Range Switch . This switch sets the pulse repetition frequency (PRF) range of
the internal oscillator. The marked value of each position is the upper limit of the
0: range, approximately. The vernier dial directly below the switch varies the PRF
within the set range.
If this switched is set to the “EXT” position, the instrument is triggered by a signal
applied to the TRIG connector, rather than by the internal oscillator.
4) TRIG Connector . When the PRF Range Switch is set to “EXT”, the instrument is
triggered by a TTL pulse applied to this connector. The pulse must be at least 50 ns
wide.
When the PRF Range Switch is set to one of the four internal oscillator ranges, this
connector is an output, which supplies a 2V, 200 ns wide pulse for each trigger
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3
24
578
9
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event. This output may be used to trigger oscilloscopes or other equipment.
5) Delay Controls . When the PRF Range Switch is set to one of the four internal
oscillator ranges, the main output is advanced or delayed relative to the TRIG
output pulse (item 4). The delay is variable up to 200 ns, approximately, using the
DELAY and DELAY FINE dials.
6) Advance/Delay Switch . When the PRF Range Switch is set to one of the four
internal oscillator ranges, this switch determines whether the TRIG output precedes
the main output (ADVANCE mode), or whether the TRIG output occurs after the
main output (DELAY mode).
7) Pulse Width Control . This dial controls the pulse width.
8) Amplitude Control . This dial controls the amplitude.
9) OUT Connector . This SMA connector provides the main output. This output
requires a 50Ω load to function properly.
Caution: Voltages as high as ±200V may be present on the center conductor of
this output connector. Avoid touching this conductor. Connect to this connector
using standard coaxial cable, to ensure that the center conductor is not exposed.
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REAR PANEL CONTROLS
1. AC POWER INPUT . An IEC-320 C14 three-pronged recessed male socket is
provided on the back panel for AC power connection to the instrument. One end of
the detachable power cord that is supplied with the instrument plugs into this socket.
2. AC FUSE DRAWER . The two fuses that protect the AC input are located in this
drawer. Please see the “FUSES” section of this manual for more information.
3. DC FUSES . These two fuses protect the internal DC power supplies. Please see the
“FUSES” sections of this manual for more information.
4. OS INPUT CONNECTOR . (Present on units with -OS option only.) A DC offset in
the range of ±50V (250 mA max) may be applied to this solder terminal. The DC
offset will appear on the output. When this feature is not used, the OS input should
be connected to ground (using the adjacent GND connector). This is especially
important when driving loads containing a diode.
5. GND CONNECTOR . (Present on units with -OS option only.) This solder terminal is
connected to ground. It may be used to ground the OS input connector.
6. AMP SWITCH & INPUT . (Present on units with -EA option only.) To control the
output amplitude with an external voltage, set the rear-panel switch to the “EXT”
position and apply 0 to +10V to the adjacent connector (RIN ≥ 10kΩ).
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OS GND
INT EXT A
AMP
2
31
5
4
6

GENERAL INFORMATION
ASIC TEST ARRANGEMENT
The AVR-A-1-S2-C should be tested with a sampling oscilloscope with a bandwidth of
at least 2 GHz to properly observe the high-speed waveform. (The cables and
attenuators must also have a bandwidth of at least 2 GHz.) A typical test arrangement
is shown below:
The attenuators are required to prevent damage to the sampling oscilloscope. A 60 d
attenuator with sufficient voltage rating should be used on the main output.
ASIC PULSE CONTROL
This instrument can be triggered by its own internal clock or by an external TTL trigger
signal. When triggered internally, two mainframe output channels respond to the trigger:
OUT and SYNC.
•OUT. This is the main output. The maximum output voltage is 10V.
•TRIG. The TRIG pulse is a fixed-width TTL-level reference pulse used to trigger
oscilloscopes or other measurement systems.
When the ADVANCE/DELAY switch is set to the ADVANCE mode, the TRIG output
precedes the main output. These pulses are illustrated below:
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AVTECH
P LSER
MAIN OUTPUT
CONNECTOR
TRIG
CONNECTOR
AC
POWER
ALL CA LES: 50 OHM COAXIAL
SAMPLING
OSCILLOSCOPE
BW > 2 GHz
50 OHM INPUT
TRIG
CONNECTOR
60 d
ATTENUATOR

When the ADVANCE/DELAY switch is set to the DELAY mode, the TRIG output lags
the main output. These pulses are illustrated below:
When triggered externally, the TRIG connector acts as an input. The delay controls do
not function in this mode. This is illustrated below:
AMPLITUDE DYNAMIC RANGE
Avtech high-speed pulse generators are optimized to operate near their maximum rated
amplitude. Generally, operation below 20% of the maximum rated amplitude is not
recommended. To generate pulses below this level, the pulse generator should be
operated near its maximum rated amplitude, and one or more coaxial attenuators
should be connected to the output.
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TRIG
(generated by the
internal oscillator)
200 ns, FIXED
MAIN OUTPUT
PULSE WIDTHDELAY
AMPLITUDE,
VARIA LE
2V, FIXED
MAIN OUTPUT
PULSE WIDTH
AMPLITUDE,
VARIA LE
> 50 ns
TTL LEVELS
(0V and 3V-5V)
TRIG
(external input)
PROPAGATION DELAY (FIXED)
TRIG
(generated by the
internal oscillator)
200 ns, FIXED
MAIN OUTPUT
PULSE WIDTH
DELAY
AMPLITUDE,
VARIA LE
2V, FIXED

Avtech suggest the Midwest Microwave ATT-0527-XX-SMA-07 family of fixed 12 GHz,
20 Watt attenuators for use with the AVR-A-1-S2-C.
For more information, please see the Avtech application note “How Can I Extend the
Amplitude Range to Low Levels?” at http://www.avtechpulse.com/appnote/techbrief11/.
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