Avtech AVR-5B-B User manual

INSTRUCTIONS
MODEL AVR-5B-B
500 VOLT, 10 kHz PULSE GENERATOR
WITH IEEE 488.2 AND RS-2 2 CONTROL
SERIAL NUMBER: 142 2
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
[e-mail]
http://www.avtechpulse.com/
Tel: [phone] (USA & Canada)
or [phone] (Worldwide)
BOX 5120, LCD MERIVALE
OTTAWA, CANADA K2C H5

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] (Worldwide)
E-mail: [email protected]
World Wide Web: http://www.avtechpulse.com
2

TABLE OF CONTENTS
WARRANTY......................................................................................................................2
TECHNICAL SUPPORT...................................................................................................2
TABLE OF CONTENTS....................................................................................................3
INTRODUCTION...............................................................................................................5
AVAILABLE OPTIONS.....................................................................................................6
HIGH-VOLTAGE PRECAUTIONS....................................................................................7
SPECIFICATIONS............................................................................................................8
REGULATORY NOTES..................................................................................................10
FCC PART 18........................................................................................................................10
EC DECLARATION OF CONFORMITY................................................................................10
DIRECTIVE 2011/65/EU (RoHS)...........................................................................................11
DIRECTIVE 2002/96/EC ( EEE)..........................................................................................11
FIRM ARE LICENSING.......................................................................................................12
INSTALLATION..............................................................................................................13
VISUAL CHECK.................................................................................................................... 13
PO ER RATINGS................................................................................................................ 13
CONNECTION TO THE PO ER SUPPLY...........................................................................13
PROTECTION FROM ELECTRIC SHOCK...........................................................................14
ENVIRONMENTAL CONDITIONS........................................................................................15
LABVIE DRIVERS..............................................................................................................15
FUSES.............................................................................................................................16
AC FUSE REPLACEMENT...................................................................................................16
DC FUSE REPLACEMENT...................................................................................................17
FUSE RATINGS.................................................................................................................... 17
FRONT PANEL CONTROLS..........................................................................................1
REAR PANEL CONTROLS............................................................................................21
GENERAL INFORMATION............................................................................................23
BASIC PULSE CONTROL....................................................................................................23
TRIGGER MODES................................................................................................................25
PULSE IDTH MODES........................................................................................................25
GATING MODES...................................................................................................................25
PREVENTING OUTPUT STAGE FAILURE..........................................................................26
OUTPUT AND LOAD IMPEDANCE (STANDARD UNITS)...........................................27

OUTPUT IMPEDANCE..........................................................................................................27
LOAD IMPEDANCE..............................................................................................................27
OUTPUT AND LOAD IMPEDANCE (-R50 UNITS)........................................................28
-R50 OPTION........................................................................................................................ 28
SAMPLE AVEFORMS FOR VARIOUS ROUT / RLOAD VALUES....................................28
DRIVING A DIODE LOAD DIRECTLY..................................................................................29
OPERATIONAL CHECK.................................................................................................31
PROGRAMMING YOUR PULSE GENERATOR...........................................................34
KEY PROGRAMMING COMMANDS....................................................................................34
ALL PROGRAMMING COMMANDS.....................................................................................35
MECHANICAL INFORMATION......................................................................................37
TOP COVER REMOVAL.......................................................................................................37
RACK MOUNTING................................................................................................................37
ELECTROMAGNETIC INTERFERENCE..............................................................................37
MAINTENANCE..............................................................................................................38
REGULAR MAINTENANCE..................................................................................................38
CLEANING............................................................................................................................38
WIRING DIAGRAMS.......................................................................................................3
IRING OF AC PO ER (STANDARD UNITS)....................................................................39
IRING OF DC PO ER....................................................................................................... 40
PCB 158R6 - LO VOLTAGE PO ER SUPPLY................................................................41
PCB 156D - POLARITY CONTROL PCB (-PN UNITS)........................................................42
PCB 197J - HIGH VOLTAGE DISCHARGE CIRCUIT..........................................................43
PCB 183A-S AND 183A-P CAPACITOR BANKS.................................................................44
PCB 104G - KEYPAD / DISPLAY BOARD...........................................................................45
MAIN IRING - POSITIVE (-P) OR NEGATIVE (-N) UNITS................................................46
MAIN IRING - DUAL-POLARITY (-PN) UNITS..................................................................47
PERFORMANCE CHECK SHEET.................................................................................48
Manual Reference: /fileserver2/officefiles/instructword/avr-5/AVR-5B-B,ed27.odt.
Last modified February 15, 2022.
Copyright © 2022 Avtech Electrosystems Ltd, All Rights Reserved.
4

INTRODUCTION
The AVR-5B-B is a high performance, GPIB and RS2 2-equipped instrument capable
of generating up to 500V at repetition rates up to 10 kHz. The pulse width is variable
from 100 ns up to 100 us, and the duty cycle may be as high as 1% (or up to 2% with
the -XP1 option, or 4% with the -XP2 option). Rise and fall times are fixed at less than
20 ns (or 0 ns for units with the -R50 option). The AVR-5B-B includes an internal
trigger source, but it can also be triggered or gated by an external source. A front-panel
pushbutton can also be used to trigger the instrument. The output pulse width can be
set to follow an input trigger pulse width.
The output voltage polarity depends on the model number:
"-P" units: up to +500 Volts
"-N" units: up to -500 Volts
"-PN" units: up to ±500 Volts
The AVR-5B-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.
5

AVAILABLE OPTIONS
-HN Option: The standard N-type output connector is replaced with an HN-type
connector.
-MHV Option: The standard N-type output connector is replaced with an MHV-type
connector.
-SHV Option: The standard N-type output connector is replaced with an SHV-type
connector.
-R5 Option: Rack-mount kit.
-R50 Option: Switchable output impedance. This allows the output impedance to be
switched between the standard value of 0Ω (nominally) or 50Ω (for
back-matching purposes).
-XP1 Option: Boosts the maximum duty cycle to 2%.
-XP2 Option: Boosts the maximum duty cycle to 4%.
6

HIGH-VOLTAGE PRECAUTIONS
CAUTION: This instrument provides output voltages as high as 500 Volts under
normal operating conditions, and generates up to 550V 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.
. 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.
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.
7

SPECIFICATIONS
Model1: AVR-5B-B
Amplitude (VOUT)2,1 : < 20 to 500 Volts
Maximum output current: 10 Amps
Output resistance (in series with
output):
Standard: Nominally zero (< 2Ω)
Optional14: Nominally zero (< 2Ω), or 50Ω, switchable
Rise & fall times (20%-80%)
into RLOAD = 50Ω: ≤ 20 ns14
Pulse width (FWHM) : 100 ns to 100 us
PRF: external trigger mode:
internal trigger:
0 to 10 kHz
1 Hz to 10 kHz
Maximum duty cycle (DCMAX), and
maximum average output power
(PMAX)16:
DCMAX, PMAX
Standard: 1%, 50W
-XP1 opt: 2%, 100W
-XP2 opt: 4%, 200W
Maximum droop at maximum pulse
width, into 50Ω12:4%
Amplitude discharge time constant,
τDIS (typical)9:2 seconds
Minimum time between full
discharges of the HV PS10:10 seconds
Amplitude charge-up time11: < 8 seconds
Polarity4: Positive or negative or both (specify -P, -N, or -PN).
Dual polarity not available with -XP2 option.
GPIB and RS-2 2 control: Standard on -B units. See http://www.avtechpulse.com/gpib for more information.
LabView Drivers: Available at http://www.avtechpulse.com/labview.
Ethernet port, for remote control
using VXI-11. , ssh, telnet, web:
Included. Recommended as a modern alternative to GPIB / RS-2 2.
See http://www.avtechpulse.com/options/vxi for details.
Settings resolution: The resolution of the timing parameters (pulse width, delay, period) varies, but is always better than
0.15% of (|set value| + 20 ns). The amplitude resolution is < 0.1% of the maximum amplitude.
Settings accuracy (into 50Ω): Typically ± % (plus ±1V or ± 2 ns) after 10 minute warmup. For high-accuracy applications
requiring traceable calibration, verify the output parameters with a calibrated oscilloscope15.
Propagation delay: ≤ 200 ns (Ext trig in to pulse out)
Jitter (Ext trig in to pulse out): ± 100 ps ± 0.0 % of sync delay
Trigger modes: Internal trigger, external trigger (TTL level pulse, > 10 ns, 1 kΩ input impedance), front-panel “Single
Pulse” pushbutton, or single pulse trigger via computer command. In the external trigger mode, the
pulse width may be set by the instrument, or it may be set to track the input pulse width.
Variable delay: Sync to main out: 0 to 1.0 seconds, for all trigger modes (including external trigger).
Sync output: > + Volts, > 50 ns, will drive 50 Ohm loads
Gated operation: Synchronous or asynchronous, active high or low, switchable. Suppresses triggering when active.
Connectors: OUT: N5,6. Trig, Sync, Gate: BNC
Power requirements: 100 - 240 Volts, 50 - 60 Hz
Dimensions (H x W x D): 100 mm x 4 0 mm x 75 mm ( .9” x 17” x 14.8”)
Chassis material: cast aluminum frame and handles, blue vinyl on aluminum cover plates
Temperature range: +5°C to +40°C
1) -B suffix indicates GPIB-equipped model.
2) For operation at amplitudes of less than 10% of full-scale, best results will be obtained by setting the amplitude near full-scale and using external
attenuators on the output.
) The output pulse width may also be controlled externally by applying a TTL-level trigger of the desired width to a rear-panel BNC connector (PWIN =
PWOUT mode).
4) Indicate desired polarity by suffixing the model number with -P or -N (i.e. positive or negative) or -PN for dual polarity option.
5) SHV, MHV or HN output connectors can also be provided. To specify, suffix the model number with -SHV, -MHV or -HN as required.
6) An N-male to BNC-female adapter (Amphenol P/N 1-216) is available. Add the suffix -ADPT2 to the model number to order this adapter.
7) An adapter kit, consisting of an SHV PLUG to MHV FEMALE adapter and an MHV MALE to BNC FEMALE adapter, is available. Add the suffix -
ADPT1 to the model number to order this kit.
8) MHV, N or HN output connectors can also be provided. To specify, suffix the model number with -MHV, -NC or -HN as required.
9) The output amplitude is controlled by internal high-voltage DC power supplies. When the amplitude setting is reduced, the high voltage decays in an
exponential fashion, with the typical time constant noted in this specification. The -QD option provides a fast active-discharge circuit.
10)More frequent discharges will cause the instrument to overheat, and may cause damage.
8

11)The output amplitude is controlled by internal high-voltage DC power supplies. This is the time required for the power supplies to rise from 5% to
95% of their full value in response to a change in settings from zero to the maximum setting.
12)Valid for 50 Ohm loads. The droop will be proportionally higher into lower resistance loads.
1 ) The instrument may be used to drive resistive loads of less than 50 Ohms, as long as the maximum output current specification is not exceeded. The
rise and fall times may increase.
14)Add the suffix -R50 to specify the switchable 0/50Ω output resistance feature. The -R50 option will increase the specified rise and fall times by 10 ns.
Not available with the -XP1 or -XP2 options. This option is useful for applications where a proper 50Ω termination at the load is impossible (for
example, testing semiconductors in cryostats), because it provides 50Ω “back-matching” at the pulser end of the transmission line (absorbing
reflections from the mismatched load).
15)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 17025:2005 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.
16)The maximum average output power is only obtainable at maximum amplitude.
9

REGULATORY NOTES
FCC PART 18
This device complies with part 18 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 ([e-mail]) 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 ([email protected]) if you require assistance.
EC DECLARATION OF CONFORMITY
We Avtech Electrosystems Ltd.
P.O. Box 5120, LCD Merivale
Ottawa, Ontario
Canada K2C H5
declare that this pulse generator meets the intent of Directive 2004/108/EG 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
10

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 61010-1:2001 Safety requirements for electrical equipment for
measurement, control, and laboratory use
DIRECTIVE 2011/65/EU (RoHS)
We Avtech Electrosystems Ltd.
P.O. Box 5120, LCD Merivale
Ottawa, Ontario
Canada K2C H5
declare that, to the best of our knowledge, all electrical and electronic equipment (EEE)
sold by the company are in compliance with Directive 2011/65/EU of the European
Parliament and of the Council of 8 June 2011 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) < 1000 ppm (0.1% by mass)
Mercury (Hg) < 1000 ppm (0.1% by mass)
Hexavalent Chromium (Cr6+) < 1000 ppm (0.1% by mass)
Polybrominated Biphenyls (PBB) < 1000 ppm (0.1% by mass)
Polybrominated Diphenyl ethers (PBDE) < 1000 ppm (0.1% by mass)
Cadmium (Cd) < 100 ppm (0.01% by mass)
Bis(2-ethylhexyl) phthalate (DEHP) < 1000 ppm (0.1% by mass)
Butyl benzyl phthalate (BBP) < 1000 ppm (0.1% by mass)
Dibutyl phthalate (DBP) < 1000 ppm (0.1% by mass)
Diisobutyl phthalate (DIBP) < 1000 ppm (0.1% 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
11

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]om).
Earlier firmware versions do not contain any open source software.
12

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 100 - 240 V, 50 - 60 Hz.
The maximum power consumption is 150 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- 20 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:
1

Destination Region Description Option Manufacturer Part Number
United Kingdom, Hong Kong,
Singapore, Malaysia
BS 1 6 ,
2 0V, 50 Hz -AC00 Qualtek 70001-E01
Australia, New Zealand AS 112:2000,
2 0-240V, 50 Hz -AC01 Qualtek 7400 -A01
Continental Europe, Korea,
Indonesia, Russia
European CEE 7/7
“Schuko” 2 0V, 50 Hz -AC02 Qualtek 64002-D01
North America, Taiwan NEMA 5-15,
120V, 60 Hz -AC0 Qualtek 12007-01
Switzerland SEV 1011,
2 0V, 50 Hz -AC06 Qualtek 78001-E01
South Africa, India SABS 164-1,
220-250V, 50 Hz -AC17 Volex 21 1H 10 C
Japan JIS 8 0 ,
100V, 50-60 Hz -AC18 Qualtek 97002-01
Israel SI 2,
220V, 50 Hz -AC19 Qualtek 98001-01
China GB 1002-1 / 2099-1,
220V, 50 Hz -AC22 Qualtek 99012-01
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.
. 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.
14

ENVIRONMENTAL CONDITIONS
This instrument is intended for use under the following conditions:
1. indoor use;
2. altitude up to 2 000 m;
. temperature 5 °C to 40 °C;
4. maximum relative humidity 80 % for temperatures up to 1 °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.
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/.
15

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:
16
Fuses #1 and #2
(AC fuses)
Fuse #4
(DC fuse)
Fuse #
(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 for standard positive (-P) models:
Fuses
Nominal
Mains
Voltage
Rating Case Size
Recommended Replacement Part
Littelfuse Part
Number
Digi-Key Stock
Number
#1, #2
(AC)
115 V 1.6A, 250V,
Time-Delay 5×20 mm 021801.6HXP F2424-ND
2 0 V 0.8A, 250V,
Time-Delay 5×20 mm 0218.800HXP F2418-ND
#
(DC) N/A 1.0A, 250V, Time-Delay 5×20 mm 0218001.HXP F2419-ND
#4
(DC) N/A 4.0A, 250V, Time-Delay 5×20 mm 0218004.HXP F2421-ND
Units with the dual-polarity (-PN) or switchable output impedance (-R50) options have
slightly different fuse requirements:
Fuses
Nominal
Mains
Voltage
Rating Case Size
Recommended Replacement Part
Littelfuse Part
Number
Digi-Key Stock
Number
#1, #2
(AC)
115 V 1.6A, 250V,
Time-Delay 5×20 mm 021801.6HXP F2424-ND
2 0 V 0.8A, 250V,
Time-Delay 5×20 mm 0218.800HXP F2418-ND
#
(DC) N/A 1.6A, 250V, Time-Delay 5×20 mm 021801.6HXP F2424-ND
#4
(DC) N/A 4.0A, 250V, Time-Delay 5×20 mm 0218004.HXP F2421-ND
17

Units with the -XP1 option (all polarities) have different fuse requirements:
Fuses
Nominal
Mains
Voltage
Rating Case Size
Recommended Replacement Part
Littelfuse Part
Number
Digi-Key Stock
Number
#1, #2
(AC)
115 V 1.6A, 250V,
Time-Delay 5×20 mm 021801.6HXP F2424-ND
2 0 V 0.8A, 250V,
Time-Delay 5×20 mm 0218.800HXP F2418-ND
#
(DC) N/A 1.0A, 250V, Time-Delay 5×20 mm 0218001.HXP F2419-ND
#4
(DC) N/A 5.0A, 250V, Time-Delay 5×20 mm 0218005.HXP F2422-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.
18

FRONT PANEL CONTROLS
1. POWER Switch . This is the main power switch. When turning the instrument on,
there is normally a delay of 10 seconds before anything is shown on the main
display, as the internal operating system boots up.
If the main menu does not appear after 0 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 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.
. OUT CONNECTOR . This N-type connector provides the output to a 50Ω (or higher)
load.
Caution: Voltages as high as ±500V 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
56
19
4
2
3
1

of + Volts to RL > 1kΩ with a pulse width of approximately 100 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.
×10 If one of the adjustable numeric parameters is displayed, this
increases the setting by a factor of ten.
÷10 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.
20