Avtech AVR-D3-B User manual

INSTRUCTIONS
MODEL AVR-D3-B
UP TO ±250 VOLTS, ±5 AMP
BIPOLAR TRANSISTOR
SEMICONDUCTOR TEST PULSER
WITH IEEE 488.2 / RS-232 / ETHERNET CONTROL
SERIAL NUMBER: 4 7
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 9 7 5
[e-mail]
http://www.avtechpulse.com/
Tel: [phone] (USA & Canada) or + -6 3-686-6675 (Intl)
Fax: 800-56 - 970 (USA & Canada) or + -6 3-686-6679 (Intl)
BOX 5 20, LCD MERIVALE
OTTAWA, CANADA K2C3H5

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 + -6 3-686-6675 (International)
Fax: 800-56 - 970 (USA & Canada) or + -6 3-686-6679 (International)
E-mail: [e-mail]
World Wide Web: http://www.avtechpulse.com
2

TABLE OF CONTENTS
WARRANTY......................................................................................................................2
TECHNICAL SUPPORT...................................................................................................2
TABLE OF CONTENTS....................................................................................................3
INTRODUCTION...............................................................................................................5
SPECIFICATIONS.............................................................................................................7
REGULATORY NOTES....................................................................................................9
FCC PART 18.......................................................................................................................... 9
EC DECLARATION OF CONFORMITY..................................................................................9
DIRECTIVE 2011/65/EU (RoHS)..........................................................................................10
DIRECTIVE 2002/96/EC ( EEE)..........................................................................................10
FIRM ARE LICENSING.......................................................................................................11
INSTALLATION..............................................................................................................12
VISUAL CHECK....................................................................................................................12
PO ER RATINGS................................................................................................................12
CONNECTION TO THE PO ER SUPPLY...........................................................................12
PROTECTION FROM ELECTRIC SHOCK...........................................................................13
ENVIRONMENTAL CONDITIONS........................................................................................14
LABVIE DRIVERS.............................................................................................................14
FUSES.............................................................................................................................15
AC FUSE REPLACEMENT...................................................................................................15
DC FUSE REPLACEMENT...................................................................................................16
FUSE RATINGS....................................................................................................................16
FRONT PANEL CONTROLS..........................................................................................17
REAR PANEL CONTROLS............................................................................................19
GENERAL INFORMATION............................................................................................21
BASIC PULSE CONTROL....................................................................................................21
TRIGGER MODES................................................................................................................22
GATING MODES...................................................................................................................23
MINIMIZING WAVEFORM DISTORTIONS....................................................................24
USE 50 OHM TRANSMISSION LINES.................................................................................24
USE LO -INDUCTANCE LOADS........................................................................................24
TYPICAL USAGE AND WAVEFORMS..........................................................................25
3

TURN-ON TEST....................................................................................................................25
TURN-OFF TEST.................................................................................................................. 26
IMPEDANCE NOTES............................................................................................................28
TRANSITION TIME NOTES..................................................................................................28
PROGRAMMING YOUR PULSE GENERATOR............................................................29
KEY PROGRAMMING COMMANDS....................................................................................29
ALL PROGRAMMING COMMANDS.....................................................................................30
OTHER INFORMATION.................................................................................................32
APPLICATION NOTES.........................................................................................................32
MANUAL FEEDBACK...........................................................................................................32
MECHANICAL INFORMATION......................................................................................33
TOP COVER REMOVAL.......................................................................................................33
RACK MOUNTING................................................................................................................ 33
ELECTROMAGNETIC INTERFERENCE..............................................................................33
MAINTENANCE..............................................................................................................34
REGULAR MAINTENANCE..................................................................................................34
CLEANING............................................................................................................................ 34
WIRING DIAGRAMS.......................................................................................................35
IRING OF AC PO ER.......................................................................................................35
PCB 158R5 - LO VOLTAGE PO ER SUPPLY................................................................36
PCB 168C - HIGH-VOLTAGE PO ER SUPPLY.................................................................37
PCB 228C - NEGATIVE UV CONTROL PCB.......................................................................38
PCB 241C - DUAL P PCB.................................................................................................39
PCB 335A - DUAL TRIGGER ENCODER............................................................................40
PCB 104G - KEYPAD / DISPLAY BOARD...........................................................................41
MAIN IRING.......................................................................................................................42
PERFORMANCE CHEC SHEET..................................................................................43
Manual Reference: /fileserver2/officefiles/instructword/avr-d3/AVR-D3-B,ed2.odt.
Last modified April 3, 202 .
Copyright © 202 Avtech Electrosystems Ltd, All Rights Reserved.
4

INTRODUCTION
The AVR-D3-B is a high performance, GPIB and RS232-equipped instrument capable
of generating the bipolar waveform shown below:
In the waveform shown above, a wide negative pulse (with pulse width PW2 and
amplitude -V2) is interrupted by a shorter positive pulse (PW , +V ). The three
highlighted transition have switching times of 20 ns or less. (The final transition to
ground is slower).
This waveform allows both turn-on and turn-off transitions to be tested, without biasing
the devices with thermally-troublesome DC currents.
The main output is normally connected to a user-supplied test circuit, similar to that
shown below:
VPULSE
ROUT = 50Ω User's
coaxial
cabling
Typical user-supplied
test circuit
AVR-D3-B-MS
OUT
MON
RMON = 50Ω
VOUT, to
oscilloscope
VCC = +30V
.25Ω
4Ω
VBB = -4V
N9 4
2N5686
VMON, to
oscilloscope VIN, to
oscilloscope
VCURR-MON, to
oscilloscope
5
V ,
+ V to +250V
V2,
- V to -250V
0V
Delay,
0 to 00 us
PW ,
0 to 00 us
tR ≤ 20 ns (20%-80%)
VPULSE
PW2,
30 to 300 us

A 50 Ohm output impedance exists between the internal pulse generator circuit and the
output connector on the front panel of the instrument.
A monitor output (“MON”) is provided as well, for monitoring the internal pulse
waveform. It can be used to sense the voltage drop across the main output resistance,
thus providing a measure of the actual output current. However, the user of a dedicated
current transformer or current probe is normally recommended for current sensing.
The AVR-D3-B features front panel keyboard and adjust knob control of the output
pulse parameters along with a four line by 40-character backlit 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.
The instrument is protected against overload conditions (such as short circuits) by an
automatic control circuit. An internal power supply monitor removes the power to the
output stage for five seconds if an average power overload exists. After that time, the
unit operates normally for one second, and if the overload condition persists, the power
is cut again. This cycle repeats until the overload is removed.
This instrument is intended for use in research, development, test and calibration
laboratories by qualified personnel.
6

SPECIFICATIONS
Model : AVR-D3-B
V amplitude: + V to +250V
V2 amplitude: - V to -250V
PW pulse width: 0 to 00 us
PW2 pulse width: 30 to 300 us
Output impedance (ROUT): 50 Ohms
Maximum output current: ±250V / ROUT = ±5 Amps
Maximum power dissipated
internally, in ROUT:(5A)2 × 50Ω × 300 us × 0 Hz = 3.75 W
Switching time (tR): ≤ 20 ns (20%-80%), as measured at the “MON” connector. The switching
times at the “OUT” connector may be slower due to the effective of ROUT
and and the cabling / circuit capacitance (CLOAD). The time constant of any
degradation will be given by τ = ROUT × CLOAD. This switching time (tR)
applies to the three transitions noted in the waveform above. The fourth
transition will be much slower.
Pulse repetition frequency Hz to 0 Hz, adjustable, or single-shot.
Supplied test jigs: None (user-supplied)
Propagation delay: ≤ 50 ns (Ext trig in to pulse out)
Jitter: ± 00 ps ± 0.03% of sync delay (Ext trig in to pulse out)
Trigger required: External trigger mode: TTL, 50 ns or wider
Sync delay: Variable 0 to ± second (sync out to pulse out)
Sync output: +3 Volts, 00 ns, will drive 50 Ohm loads
Gated operation: Active high or low, switchable.
Connectors: Out, Trig, Sync, Gate: BNC
GPIB & RS-232 control : Standard feature on all -B units.
LabView drivers: Available for download at http://www.avtechpulse.com/labview.
Ethernet port, for remote Included. Recommended as a modern alternative to GPIB / RS-232.
7
V ,
+ V to +250V
V2,
- V to -250V
0V
Delay,
0 to 00 us
PW ,
0 to 00 us
tR ≤ 20 ns (20%-80%)
VPULSE
PW2,
30 to 300 us

control using VXI- .3, ssh,
telnet, & web: See http://www.avtechpulse.com/options/vxi for details.
Settings resolution: The resolution of the timing parameters varies, but is always
better than 0. 5% of the set value. The amplitude resolution is
typically 0.02% of the maximum amplitude.
Settings accuracy: Typically ± 3% (plus ± V or ± 2 ns) after 0 minute warmup.
For high-accuracy applications requiring traceable calibration,
verify the output parameters with a calibrated oscilloscope2.
Power requirements: 00 - 240 Volts, 50 - 60 Hz
Dimensions: 00 mm x 430 mm x 375 mm (3.9” x 7” x 4.8”)
Chassis material: Cast aluminum frame and handles, blue vinyl on aluminum cover plates
Mounting: Any. Add -R5 to the model number to add a rack-mount kit.
Temperature range: +5°C to +40°C
) -B suffix indicates IEEE-488.2 GPIB and RS-232 control of amplitude and frequency. See http://www.avtechpulse.com/gpib for
details.
2) These instruments are provided with a basic calibration checksheet, showing a selection of measured output parameters. These
measurements are performed with equipment that is calibrated on a regular basis by a third-party ISO/IEC 7025:2005 accredited
calibration laboratory. However, Avtech itself does not claim any accreditation. For applications requiring traceable performance,
use a calibrated measurement system rather than relying on the accuracy of the pulse generator settings.
8

REGULATORY NOTES
FCC PART 8
This device complies with part 8 of the FCC rules for non-consumer industrial,
scientific and medical (ISM) equipment.
This instrument is enclosed in a rugged metal chassis and uses a filtered power entry
module (where applicable). The main output signal is provided on a shielded connector
that is intended to be used with shielded coaxial cabling and a shielded load. Under
these conditions, the interference potential of this instrument is low.
If interference is observed, check that appropriate well-shielded cabling is used on the
output connectors. Contact Avtech ([email protected]) for advice if you are unsure
of the most appropriate cabling. Also, check that your load is adequately shielded. It
may be necessary to enclose the load in a metal enclosure.
If any of the connectors on the instrument are unused, they should be covered with
shielded metal “dust caps” to reduce the interference potential.
This instrument does not normally require regular maintenance to minimize interference
potential. However, if loose hardware or connectors are noted, they should be
tightened. Contact Avtech ([e-mail]) if you require assistance.
EC DECLARATION OF CONFORMITY
We Avtech Electrosystems Ltd.
P.O. Box 5 20, LCD Merivale
Ottawa, Ontario
Canada K2C 3H5
declare that this pulse generator meets the intent of Directive 2004/ 08/EG for
Electromagnetic Compatibility. Compliance pertains to the following specifications as
listed in the official Journal of the European Communities:
EN 5008 - Emission
EN 50082- Immunity
9

and that this pulse generator meets the intent of the Low Voltage Directive 2006/95/EC.
Compliance pertains to the following specifications as listed in the official Journal of the
European Communities:
EN 6 0 0- :200 Safety requirements for electrical equipment for
measurement, control, and laboratory use
DIRECTIVE 20 /65/EU (RoHS)
We Avtech Electrosystems Ltd.
P.O. Box 5 20, LCD Merivale
Ottawa, Ontario
Canada K2C 3H5
declare that, to the best of our knowledge, all electrical and electronic equipment (EEE)
sold by the company are in compliance with Directive 20 /65/EU of the European
Parliament and of the Council of 8 June 20 on the restriction of the use of certain
hazardous substances in electrical and electronic equipment (also known as “RoHS
Recast”). In addition, this declaration of conformity is issued under the sole
responsibility of Avtech Electrosystems Ltd. Specifically, products manufactured do not
contain the substances listed in the table below in concentrations greater than the listed
maximum value.
Material/Substance Threshold level
Lead (Pb) < 000 ppm (0. % by mass)
Mercury (Hg) < 000 ppm (0. % by mass)
Hexavalent Chromium (Cr6+) < 000 ppm (0. % by mass)
Polybrominated Biphenyls (PBB) < 000 ppm (0. % by mass)
Polybrominated Diphenyl ethers (PBDE) < 000 ppm (0. % by mass)
Cadmium (Cd) < 00 ppm (0.0 % by mass)
Bis(2-ethylhexyl) phthalate (DEHP) < 000 ppm (0. % by mass)
Butyl benzyl phthalate (BBP) < 000 ppm (0. % by mass)
Dibutyl phthalate (DBP) < 000 ppm (0. % by mass)
Diisobutyl phthalate (DIBP) < 000 ppm (0. % by mass)
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 WEEE
compliance (as mandated in Directive 2002/96/EC of the European Union and local
0

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.
FIRMWARE LICENSING
Instruments with firmware versions 5.00 or higher use open-source software internally.
Some of this software requires that the source code be made available to the user as a
condition of its licensing. This source code is available upon request (contact
[email protected]m).
Earlier firmware versions do not contain any open source software.

INSTALLATION
VISUAL CHECK
After unpacking the instrument, examine to ensure that it has not been damaged in
shipment. Visually inspect all connectors, knobs, liquid crystal displays (LCDs), and the
handles. Confirm that a power cord, a GPIB cable, and two instrumentation manuals
(this manual and the “Programming Manual for -B Instruments”) 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 00 - 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:
2

Destination Region Description Option Manufacturer Part Number
United Kingdom, Hong Kong,
Singapore, Malaysia
BS 363,
230V, 50 Hz -AC00 Qualtek 37000 -E0
Australia, New Zealand AS 3 2:2000,
230-240V, 50 Hz -AC0 Qualtek 374003-A0
Continental Europe, Korea,
Indonesia, Russia
European CEE 7/7
“Schuko” 230V, 50 Hz -AC02 Qualtek 364002-D0
North America, Taiwan NEMA 5- 5,
20V, 60 Hz -AC03 Qualtek 3 2007-0
Switzerland SEV 0 ,
230V, 50 Hz -AC06 Qualtek 37800 -E0
South Africa, India SABS 64- ,
220-250V, 50 Hz -AC 7 Volex 2 3 H 0 C3
Japan JIS 8303,
00V, 50-60 Hz -AC 8 Qualtek 397002-0
Israel SI 32,
220V, 50 Hz -AC 9 Qualtek 39800 -0
China GB 002- / 2099- ,
220V, 50 Hz -AC22 Qualtek 3990 2-0
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:
. 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.
3

ENVIRONMENTAL CONDITIONS
This instrument is intended for use under the following conditions:
. indoor use;
2. altitude up to 2 000 m;
3. temperature 5 °C to 40 °C;
4. maximum relative humidity 80 % for temperatures up to 3 °C decreasing
linearly to 50 % relative humidity at 40 °C;
5. Mains supply voltage fluctuations up to ± 0 % of the nominal voltage;
6. no pollution or only dry, non-conductive pollution.
LABVIEW DRIVERS
A LabVIEW driver for this instrument is available for download on the Avtech web site,
at http://www.avtechpulse.com/labview. A copy is also available in National Instruments'
Instrument Driver Library at http://www.natinst.com/.
4

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:
5
Fuse
Drawer
Pry out the fuse
drawer using a
screwdriver.
Fuses #1 and #2
AC fuses)
Fuse #4
DC fuse)
Fuse #3
DC fuse)

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
# , #2 (AC) 00-240V 0.5A, 250V,
Time-Delay 5×20 mm 02 8.500HXP F24 6-ND
#3 (DC) N/A .0A, 250V,
Time-Delay 5×20 mm 02 800 .HXP F24 9-ND
#4 (DC) N/A .6A, 250V,
Time-Delay 5×20 mm 02 80 .6HXP F2424-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.
6

FRONT PANEL CONTROLS
. POWER Switch . This is the main power switch. When turning the instrument on,
there is normally a delay of 0 seconds before anything is shown on the main
display, as the internal operating system boots up.
If the main menu does not appear after 30 seconds, turn off the instrument and
leave it off for at least 60 seconds before applying power again.
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
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.
Note that the output stage will safely withstand a short-circuited load condition.
3. OUT CONNECTOR . This BNC connector provides the main output signal, into load
impedances of 0Ω or higher.
Caution: Voltages as high as ±250V 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.
4. SYNC OUT . This connector supplies a SYNC output that can be used to trigger
other equipment, particularly oscilloscopes. This signal leads (or lags) the main
output by a duration set by the "DELAY" controls and has an approximate amplitude
2
3
4
6
5
7

of +3 Volts to RL > 50Ω with a pulse width of approximately 00 ns.
5. LIQUID CRYSTAL DISPLAY (LCD) . This LCD is used in conjunction with the
keypad to change the instrument settings. Normally, the main menu is displayed,
which lists the key adjustable parameters and their current values. The
“Programming Manual for -B Instruments” describes the menus and submenus in
detail.
6. KEYPAD .
Control Name Function
MOVE This moves the arrow pointer on the display.
CHANGE This is used to enter the submenu, or to select the operating
mode, pointed to by the arrow pointer.
× 0 If one of the adjustable numeric parameters is displayed, this
increases the setting by a factor of ten.
÷ 0 If one of the adjustable numeric parameters is displayed, this
decreases the setting by a factor of ten.
+/- If one of the adjustable numeric parameters is displayed, and
this parameter can be both positive or negative, this changes
the sign of the parameter.
EXTRA FINE This changes the step size of the ADJUST knob. In the extra-
fine mode, the step size is twenty times finer than in the normal
mode. This button switches between the two step sizes.
ADJUST This large knob adjusts the value of any displayed numeric
adjustable values, such as frequency, pulse width, etc. The
adjust step size is set by the "EXTRA FINE" button.
When the main menu is displayed, this knob can be used to
move the arrow pointer.
8

REAR PANEL CONTROLS
Note: some connectors may be in different positions than shown above, depending on
the exact combination of options ordered.
. AC POWER INPUT . An IEC-320 C 4 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. GATE . This TTL-level (0 and +5V) logic input can be used to gate the triggering of
the instrument. This input can be either active high or active low, depending on the
front panel settings or programming commands. (The instrument triggers normally
when this input is unconnected). When set to active high mode, this input is pulled-
down to ground by a kΩ resistor. When set to active low mode, this input is pulled-
up to +5V by a kΩ resistor.
5. TRIG . This TTL-level (0 and +5V) logic input can be used to trigger the instrument, if
the instrument is set to triggering externally. The instrument triggers on the rising
edge of this input. The input impedance of this input is kΩ. (Depending on the
length of cable attached to this input, and the source driving it, it may be desirable to
add a coaxial 50 Ohm terminator to this input to provide a proper transmission line
termination. The Pasternack (www.pasternack.com) PE6008-50 BNC feed-thru 50
Ohm terminator is suggested for this purpose.)
9
GATE
RS-232
GPIB
TRIG
MON
3
45 9
2
6 7
8

6. GPIB Connector . A standard GPIB cable can be attached to this connector to allow
the instrument to be computer-controlled. See the “Programming Manual for -B
Instruments” for more details on GPIB control.
7. RS-232 Connector. A standard serial cable with a 25-pin male connector can be
attached to this connector to allow the instrument to be computer-controlled. A user
name (“admin”) and a password (“default”, as shipped from the factory) are required
when logging into a serial terminal session. The internal controller attempts to auto-
sense the parity setting. It may be necessary to send a few return characters before
attempting a login in order to provide enough data to allow this auto-sensing to work.
(A standard Linux “agetty” process is used to implement serial control internally.) See
the “Programming Manual for -B Instruments” for more details on RS-232 control.
8. Network Connector . This Ethernet connector allows the instrument to be remotely
controlled using the VXI- .3, ssh (secure shell), telnet, and http (web) protocols. See
the “Programming Manual for -B Instruments” for more details.
9. MON Connector. This output may be used to sense the voltage drop across the main
output resistance, thus providing a measure of the actual output current. It is
connected to the internal pulse generator (VPULSE) through a 50Ω resistance. The MON
output should operate into a load impedance of 50Ω or higher. If a 50Ω load is used,
note that a 2: voltage divider effect will occur. If this output is not used, it should be
covered with a metal BNC dust cap, to prevent interference with other equipment.
Caution: Voltages as high as ±250V 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.
20