BK Precision 4017B User Manual
INSTRUCTION
10MHz DDS SWEEP/FUNCTION GENERATOR
MANUAL
Model 4017B
0
Table of Contents
1. Introduction to the Model 4017B 2
1.1. Description ...................................................................................................................................................................................2
1.2.
Feature Summary
2.
Front panel
2.1. Brief description. Using the controls. ..........................................................................................................................................2
2.2.
.........................................................................................................................................................................................2
Buttons and knobs. LED functionality description.
3. Operating the Model 4017B........................................................................................................................................... 6
3.1. Parameter’s setting....................................................................................................................................................................6
3.1.1. Frequency setting (except FREQCOUNTER mode). ..........................................................................................................6
3.1.2. Level setting (except FREQCOUNTER mode)...................................................................................................................8
3.1.3. Offset setting (except FREQCOUNTER mode)..................................................................................................................8
3.1.4. Duty cycle setting (except FREQCOUNTER mode). .........................................................................................................9
3.1.5. CMOS level setting (except FREQCOUNTER mode). ......................................................................................................9
3.1.6. Sweep time setting (only for INTERNAL SWEEP mode). ................................................................................................9
3.1.7. Sweep width setting (only for INTERNAL SWEEP mode). ............................................................................................10
3.1.8.
3.2. Mode description......................................................................................................................................................................10
3.2.1 EXTERNAL VCG (External Voltage Control Generator...........................................................................................10
3.2.2 INTERNAL SWEEP........................................................................................................................................................12
3.2.3 FREQCOUNTER (Frequency Counter mode).............................................................................................................13
3.2.4 Saving the default loaded mode at power-up ................................................................................................................14
3.2.5 Setting parameters examples...........................................................................................................................................14
3.3 Remote operation.....................................................................................................................................................................25
3.3.1 Brief command description ................................................................................................................................................25
3.3.2 Commands description .......................................................................................................................................................25
3.3.3 Remote program examples..............................................................................................................................................34
Gate setting (only for FREQCOUNTER mode).
3.2.1.1 Selecting EXTERNAL VCG mode.............................................................................................................................12
3.2.1.2 Selecting output waveform..........................................................................................................................................12
3.2.1.3 Selecting the frequency ...............................................................................................................................................12
3.2.1.4 Selecting the level........................................................................................................................................................13
3.2.1.5 Selecting the offset ......................................................................................................................................................13
3.2.1.6 Selecting the duty cycle...............................................................................................................................................13
3.2.1.7 Selecting output TTL/CMOS level .............................................................................................................................13 .
3.2.2.1 Selecting INTERNAL SWEEP mode .........................................................................................................................12
3.2.2.2 Selecting output waveform..........................................................................................................................................12
3.2.2.3 Selecting the frequency ...............................................................................................................................................12
3.2.2.4 Selecting the level........................................................................................................................................................13
3.2.2.5 Selecting the offset ......................................................................................................................................................13
3.2.2.6 Selecting the duty cycle...............................................................................................................................................13
3.2.2.7 Selecting output TTL/CMOS level .............................................................................................................................13
3.2.2.8 Selecting sweep width .................................................................................................................................................13
3.2.2.9 Selecting sweep time ...................................................................................................................................................13
3.2.2.10
3.2.3.1 Selecting FREQCOUNTER mode ..............................................................................................................................14
3.2.3.2 Selecting gate period ...................................................................................................................................................14
3.2.5.1 Example of setting parameters in EXTERNAL VCG mode ......................................................................................14
3.2.5.2 Example of setting parameters in INTERNAL SWEEP mode ..................................................................................16
3.2.5.3 Example of setting gate period in FREQCOUNTER mode .......................................................................................19
3.2.5.4 Example of saving the default mode at power-up ......................................................................................................19
3.2.5.5 Waveform examples ....................................................................................................................................................20
3.3.2.1 General rules................................................................................................................................................................25
3.3.2.2 Commands description ................................................................................................................................................26
3.3.3.1 Example of setting parameters in EXTERNAL VCG mode using REMOTE control mode ....................................34
3.3.3.2 Example of setting parameters in INTERNAL SWEEP mode using REMOTE control mode ................................35
3.3.3.3
Selecting type of sweeping ....................................................................................................................... 13
Example of setting parameters in FREQCOUNTER mode using REMOTE control mode
4 Specifications ............................................................................................................................................................... 37
5 Service Information.................................................................................................................................................... 38
........................................................................................................................................................ 2
........................................................................................................ 3
................................................................................................. 10
................................. 36
1
1. Introduction to the 4017B.
1.1 Description
The B&K Precision Model 4017B Sweep/Function Generator is the newest 40XX family member. The 4017B enhances the
performance achieved by its successful predecessor, BK Precision Model 4017A Sweep/Function Generator. These performances are
achieved by using direct digital waveform synthesis (DDS) techniques for generating high accuracy and precision frequencies. A high
performance Digital Signal Processor (DSP) controls every aspect of the DDS system, and is used for precise generation and processing
of waveforms. The 4017B has a vast number of applications in both analog and digital electronics, in the engineering, manufacturing,
servicing, educational and hobbyist fields. This versatile signal source is capable of generating waveform (such as sine, triangle and
square), pulse generation (through variable symmetry) and frequency sweep. Additionally, the instrument provides a built-in frequency
counter.
The core of the function generator is a DSP, which is used to generate precision sine, square or triangle waveforms over 0.01Hz to
10MHz range. This encompasses subaudible, audio, ultrasonic and RF applications. The symmetry of the waveforms can be changed
between 0% to 100% in 1% step, converting the instrument to a pulse generator capable of generating rectangular waves or pulses, ramp
or sawtooth waves and slued sine waves. An external voltage may be used to control operating frequency that can be changed using a
ratio between 1:1 and 1:100. Frequency sweep can be adjusted by changing the rate and the time sweep, and also the manner in which
frequency is changed, linear or logarithmic.
The B&K Precision Model 4017B has 3 jacks: 2 for output and 1 input. The OUTPUT jack is the main signal output. The TTL/CMOS
jack is a TTL/CMOS compatible square wave output. The VCG/SWEEP jack is an input used for controlling the operating frequency
and input to frequency counter.
The 4017B is capable of supplying an output level of 20.0V
the OUTPUT jack. The output impedance is 50 ohms; therefore the 50 ohm loaded output level is 10.0V
capability of ±5.0 V
worked on. The offset level can be adjusted with a resolution of 1mV.
The 4017B is capable of generating a TTL/CMOS compatible square wave on TTL/CMOS jack. The output level can be up to 14.0
V
(unloaded).
pp
On the VCG/SWEEP input jack, DC levels can be applied between 0V to 10.0V in order to change the output operating frequency with
a ratio between 1:1 and 1:100. This jack is also used as a frequency counter input, for frequencies between 5Hz and 100MHz.
The front panel of the Model 4017B includes LCD display, buttons, “intelligent” knobs and an LED in order to operate the unit quick
and easy. The “intelligent” knobs are one of the main features of this new model, which reduces the number of controls needed for
changing the value of a parameter. The LCD display is a large 2-line 16 columns back lighted display.
The unit also features an EIA-RS232 connector on the rear of the unit. This permits the user to remote control the 4017B using ASCII
characters. No special hardware or protocols are needed; any dumb terminal or computer serial port can be used. The baud rate is fixed
to 9600 BPS.
. The output level can be adjusted with a resolution of 1mV and 10mV, depending on the level range being
pp
with an offset voltage of ± 10.0V
pp
(unloaded) on the main signal output,
pp
, with an offset voltage
pp
1.2 Feature Summary
2. Front panel.
2.1 Brief description.
Located on the Front Panel is the LCD display, controls, power switch, connection jacks and LED (see the figure 2 for details).
The LCD display is a backlit, 2-row 16-columns LCD display.
There are two kinds of controls: buttons and knobs.
All buttons are implemented as 1-parameter single function control, except the range buttons that have a second function. Pressing the
range buttons (UP and DOWN buttons) twice at the same time will save the current working state as the default loaded state at powerup. Pressing any other buttons at the same time will have no effect upon the current working state. There are 2 kinds of buttons: one
category has no LED’s, the other category has LED’s. Pressing one of the buttons from the first category will change the values on the
LCD display.
The knobs are implemented as 3-parameter single function control, with “intelligent” control. The parameters defining an knob are:
value, rotation’s direction, and rotation’s speed. The value identifies the parameter being changed. The rotation’s direction, clockwise or
counter clockwise, determines whether the value of the parameter is increment or decrement respectively, by an amount of 1. The speed
of rotation sets the position in the parameter’s digits of the digit being modified. The “intelligent knob” implementation allows a very
simple and intuitive way of changing parameter values and reducing the number of controls used.
2
®
p
Ω
2.2 Buttons and knobs. LED functional description.
7
1
4 3 2
POWER
FREQUENCY
22.222KHz 100k
1.01 V Out
LEVEL
Peak-to-Peak
(into 50Ω)
FREQUENCY
UP
DOWN
ut
Range
WIDTHTIME
SWEEP
INT
EXT
-20dB
LIN
LOG
20
23
21
24 25 26
29
22
27 28
30 31
waveform frequency or the frequency measured sampling COUNTER IN input. The second line is used to display other parameters of
the generated waveform, depending on the mode being worked: level, offset introduced, TTL/CMOS level, duty cycle when in
EXTERNAL VCG mode, and additional parameters, time and width sweep when in INTERNAL SWEEP mode. In
FREQCOUNTER mode on the second line, the gate used in sampling COUNTER IN input is displayed.
depending on the working mode. If in EXTERNAL VCG or INTERNAL SWEEP, the value represents the generated waveform
frequency on the main output source, OUTPUT jack, and it is a 5-digit resolution value. If in FREQCOUNTER mode, the value
represents the frequency of the signal sampled on COUNTER IN input, and can be a 9-digit resolution value.
Frequency unit value. This field will display the multiplying factor used for displaying frequency value. It changes when the
user modifies the range using “UP” and “DOWN” buttons.
Frequency range. This field will display the range in which the frequency value displayed in frequency field can be changed.
It changes when user modifies the range using “UP” and “DOWN” buttons.
LCD Display. This is a 2 line X 16 columns LCD-large type display. The first line will always display the generated
1
2
Frequency field. This field is used for displaying parameter frequency. The value displayed has a different meaning
3
4
9
85 6
COUNTER
VCG
SWEEP
32
10
33
12 13
11
CMOS
TTL
COUNTER IN
34
14
TTL CMOS VCG SWEEP
35
36
15
16
WAVEFORM
37
38
17 19
18
OUTPUT LEVELDUTY CYCLE CMOS LEVEL DC OFFSET
OUTPUT
50
39
40
3
5
Range buttons. Pressing those buttons will change the frequency range. Pressing the UP and DOWN buttons means that
frequency range will change up and down, respectively. If reaching the upper or lower range by pressing the UP or DOWN buttons, it
will pass to the lower range or upper range, respectively. Changing the range will affect the frequency field, frequency unit value and
frequency range.
By pressing these two buttons together twice, the current mode and parameters will be saved as the default power-up working state.
-20 dB button. Pressing this button will engage/disengage 20dB attenuation in the signal on OUTPUT jack. Pressing this
6
button will change the level field. A light at - 20dB LED indicates engaging the attenuator. No light at –20dB LED indicates
disengaging the attenuator.
7
– 20 dB LED. LED associated with the – 20 dB button has a solid light when the attenuator is active, and no light when
attenuator is disabled.
8
COUNTER/VCG SWEEP button. Pressing this button will engage/disengage FREQCOUNTER mode. Engaging
FREQCOUNTER mode will change the content of LCD display and will also be indicated by a lighted COUNTER LED only.
Disengaging FREQCOUNTER mode will change the content of the LCD display and will also be indicated by a lighted VCG
SWEEP LED only.
9
COUNTER LED. LED is associated with COUNTER/VCG SWEEP button that lights when FREQCOUNTER mode is
active.
10
VCG SWEEP LED. LED is associated with COUNTER/VCG SWEEP button and lights when EXTERNAL VCG or
INTERNAL SWEEP mode is active, and it is associated with a lighted EXT LED or INT LED respectively.
11
TTL/CMOS button. Pressing this button will enable/disable the use of CMOS LEVEL knob. If enabled, the CMOS LED is
lighted and the output level on TTL/CMOS output jack can be changed. If disabled, the TTL LED is lighted and there will be a fixed
level on TTL/CMOS output jack.
12
TTL LED. LED is associated with TTL/CMOS button, and lights when there is an output of a fixed TTL style signal on
TTL/CMOS output jack.
13
CMOS LED. LED is associated with TTL/CMOS button and lights when there is an output of a variable CMOS style signal
on TTL/CMOS output jack.
14
SINE WAVE SELECT button. Pressing this button will enable outputting of a sine style waveform on main output,
OUTPUT jack, and will be indicated by a lighted SINE WAVE LED.
15
SINE WAVE SELECT LED. LED associated with
style signal on OUTPUT jack.
16
SQUARE WAVE SELECT button. Pressing this button will enable outputting of a square style waveform on main output,
OUTPUT jack, and it will be indicated by a lighted SQUARE WAVE SELECT LED.
17
SQUARE WAVE SELECT LED. LED associated with SQUARE WAVE SELECT button, it lights when unit outputs a
square wave style signal on OUTPUT jack.
SINE WAVE SELECT button, it lights when unit outputs a sine wave
4
18
TRIANGLE WAVE SELECT button. Pressing this button will enable outputting of a triangle style waveform on main
output, OUTPUT jack, and it will be indicated by a lighted TRIANGLE WAVE SELECT LED.
19
TRIANGLE WAVE SELECT LED. LED associated with TRIANGLE WAVE SELECT button, it lights when unit
outputs a triangle wave style signal on OUTPUT jack.
20
OTHER PARAMETERS field. This field is used for showing other parameters’ values of the output signal on the OUTPUT
jack such as level, offset, duty cycle, sweep time, sweep width or the CMOS output level on TTL/CMOS jack. As long as the value of
a parameter during a 7-second period is not changed, the unit will automatically show the output level on the OUTPUT jack.
21
OTHER PARAMETERS identifiers. This field is associated with OTHER PARAMETERS field and will show a message
relevant to the nature of the parameter value shown in OTHER PARAMETERS field. As long as the value of a parameter during a 7-
second period is not changed, the unit will automatically display the message identifying the output level parameter.
22
POWER switch. Turns power on and off.
23
FREQUENCY knob. This knob controls the changing of the frequency within the current frequency range. The value is
displayed in frequency field. The changes are applied upon the start frequency in EXTERNAL VCG and INTERNAL SWEEP mode.
(See chapter x for a detailed explanation).
This knob has no meaning in FREQCOUNTER mode.
24
SWEEP TIME knob. This knob controls the changing of the time value set for sweeping the range between start frequency
and stop frequency. This knob has no meaning except INTERNAL SWEEP mode.
25
SWEEP WIDTH knob. This knob controls the changing of the ratio used for calculation of the width of frequency range,
swept in INTERNAL SWEEP mode. This knob has no meaning except in INTERNAL SWEEP mode.
26
SWEEP INT/EXT button. Pressing this button will change the working mode between EXTERNAL VCG and
INTERNAL SWEEP. The new mode will be indicated by the lighting of the corresponding LED, INT LED or EXT LED.
27
EXT LED. LED is associated to SWEEP INT/EXT button and lights when EXTERNAL VCG mode is active.
28
INT LED. LED is associated to SWEEP INT/EXT button and lights when INTERNAL SWEEP mode is active.
29
SWEEP LIN/LOG button. Pressing this button will change the way the frequency range in INTERNAL SWEEP mode will
sweep between linear mode and logarithm mode. The lighting of the corresponding LED, LIN LED or LOG LED will indicate the
working sweep mode. Button is valid only in INTERNAL SWEEP mode.
30
LOG LED. LED is associated to SWEEP LIN/LOG button and lights when logarithm sweep mode is engaged.
31
LIN LED. LED is associated to SWEEP LIN/LOG button and lights when linear sweep mode is engaged.
32
DUTY CYCLE knob . This knob controls the changing of the duty cycle of the output waveform on OUTPUT jack. It has
meaning only for EXTERNAL VCG and INTERNAL SWEEP.
5
33
DUTY CYCLE LED. LED is associated with DUTY CYCLE knob and lights when the waveform is asymmetric.
34
CMOS LEVEL knob. This knob controls the changing of the CMOS level on the output of TTL/CMOS jack. This knob has
meaning only for EXTERNAL VCG and INTERNAL SWEEP. It is only active if TTL/CMOS button enables it. The CMOS LED
must be lit.
35
VCG SWEEP/COUNTER IN jack. Input jack is used to control the output frequency in EXTERNAL VCG mode or as
frequency count input in FREQCOUNTER mode.
36
TTL/CMOS jack. Output jack is used for supplying a fixed TTL style signal or variable CMOS style signal, depending of
the TTL/CMOS button, whose frequency is the same as the signal’s frequency on the main output, OUTPUT jack.
37
DC OFFSET knob. This knob controls the offset level added to the signal outputted on the OUTPUT jack. It has an LED
associated, DC OFFSET LED, which lights when the offset added is not zero. This knob has meaning only in EXTERNAL VCG and
INTERNAL SWEEP.
38
DC OFFSET LED. LED associated with DC OFFSET knob, lights when the value of offset added to the signal on the
OUTPUT jack is not zero.
39
OUTPUT LEVEL knob. This knob controls the output level on main output, OUTPUT jack. This knob has meaning only in
EXTERNAL VCG and INTERNAL SWEEP.
40
OUTPUT jack. The main output jack, used to supply the desired waveform, defined by frequency, level, offset, duty cycle
for EXTENAL VCG mode and moreover time and width sweep for INTERNAL SWEEP mode.
3. Operating the Model 4017B.
There are 2 modes of controlling the unit and 3 modes of operating the unit. One of the control modes uses the front panel; the other
mode is by remote, using the RS232 interface. Each mode of control excludes the other. When you are using the front panel you cannot
control the unit by remote. Engaging remote mode, using special command, deactivates the use of front panel controls. Disengaging the
remote control by using a special command enables the use of front panel button.
The 3 modes of operating are EXTERNAL VCG (external voltage control generator), INTERNAL SWEEP and FREQCOUNTER
(frequency counter).
Section 3.1. - Mode description will describe the setting of operating modes using front panel controls. Section 3.2.-Remote operation,
will have a complete description of the remote control mode.
3.1.
Parameter’s setting
3.1.1. Frequency setting (except FREQCOUNTER mode).
The f
requency setting depends on the mode being worked. On EXTERNAL VCG mode, output frequency depends on the value set by
turning the FREQUENCY knob and the DC value applied to VCG/SWEEP input jack. On INTERNAL SWEEP mode, since
frequency is sweeping a range, the value set by turning the FREQUENCY knob represents the start frequency of the range being swept.
For all modes (except FREQCOUNTER mode), frequency is displayed on the first line, using a 5-digit field and a decimal point,
whose position depends on the selected range. The unit is displayed after the frequency value field. The frequency range used is always
displayed on the right of the first line.
6
There are 5 frequency ranges available, which allows the user to set desired frequency between 0.00Hz and 10.000MHz. Pressing UP
and DOWN buttons will change the range. Within every range the frequency can be changed with a 5-digit resolution using
FREQUENCY knob.
The table below shows the frequency limits for every range, measuring unit and how it displays the frequency range:
Range Lower Value Upper Value Unit Displayed frequency range
1 0.00 999.99 Hz 1k
2 1.0000 9.9999 KHz 10k
3 10.000 99.999 KHz 100k
4 100.00 999.99 KHz 1M
5 1.0000 10.000 MHz 10M
On the TTL/CMOS output jack there is a CMOS or TTL style signal, depending on the selection of TTL/CMOS button, with the
same frequency as the signal outputted on OUTPUT jack (see section 3.1.z. for details).
Table 1: Frequency ranges
Frequency setting in EXTERNAL VCG mode.
Whether or not a DC level is applied on the VCG/SWEEP input jack, turning the FREQUENCY knob will force the unit to display the
frequency value outputted on the LCD display if 0 volts is applied on VCG/SWEEP input jack (but only on the period that the knob is
being turned). To have certain results, 0 volts must be applied on the VCG/SWEEP input jack.
Use UP and DOWN buttons to select the appropriate range then turn the FREQUENCY knob till you reach the desired frequency (see
Table1 for range’s details).
Applying a DC value between 0 V and +10V will cause a frequency decrease, on a ratio between 1:1 and 1:100. Applying 0 V DC value
will have no effect on the output frequency but applying a + 10.0V will decrease the output frequency 100 times.
For certain output frequencies, apply fixed DC levels on VCG/SWEEP jack.
Varying the positive DC level on VCG/SWEEP jack will cause the output frequency to sweep. The output frequency will follow the
changes in DC level.
ATTENTION: If the DC level applied on VCG/SWEEP jack causes the output frequency to decrease under the range limit, then
output frequency will not be limited to the lowest frequency allowed in that range. It will be displayed using the
current range displaying rules.
INTERNAL SWEEP mode frequency setting.
The value displayed on the frequency value field on the LCD display represents the instant output frequency and is updated on the LCD
display every 0.1s.
Use UP and DOWN buttons to select the appropriate range of the sweep start frequency. The FREQUENCY knob is used to select the
sweep start frequency within a range (see Table1 for range’s details).
The sweep is always done from the start frequency down to stop frequency. The start frequency is always greater then the stop
frequency. The stop frequency can reach a maximum of 1:100 of start frequency (see subchapter 3.1.x for learning how to set the stop
frequency). The unit reaches the stop frequency after a time, which can be set between 0.01s and 30.00s, with 0.01s resolution (see
subchapter 3.1.y for learning how to set the time sweep).
Turning the FREQUENCY knob will force the unit to display the sweep start frequency. Each time the sweep start frequency is
modified, either by pressing the UP or DOWN button or turning the FREQUENCY knob, the sweep will be reinitialized and the unit
will start outputting from the start frequency again.
INTERNAL SWEEP mode frequency setting.
7
The value displayed on the frequency value field on the LCD display represents the instant output frequency and is updated on the LCD
display every 0.1s.
Use the UP and DOWN buttons to select the appropriate range of the sweep start frequency. The FREQUENCY knob is used to select
the sweep start frequency within a range (see Table1 for range’s details).
The sweep is always done from the start frequency down to stop frequency, thus start frequency is always greater then the stop
frequency. The stop frequency can reach a maximum of 1:100 of start frequency (see subchapter 3.1.x for learning how to set the stop
frequency). The unit reaches the stop frequency after a time, which can be set between 0.01s and 30.00s, with 0.01s resolution (see
subchapter 3.1.y for learning how to set the time sweep).
Turning the FREQUENCY knob will force unit to display the sweep start frequency. Each time the sweep start frequency is modified,
either by pressing the UP or DOWN button or turning the FREQUENCY knob, the sweep will reinitialized and unit will start
outputting again from the start frequency.
ATTENTION:
instant frequencies will be displayed using the current range displaying rules.
If stop frequency is under the current lower range limit, the frequency sweep will not stop at the range limit; the
3.1.2. Level setting (except FREQCOUNTER mode).
This section describes the setting of the signal level at the main output jack, OUTPUT jack.
Level can be set between 10mV
engaging/disengaging the –20dB attenuate on the signal path (see Table2 for details). The –20dB LED associated with the button will
light when the –20dB attenuate is engaged. Turning the OUTPUT LEVEL knob will change the level value within the current range.
and 10.0V
p-p
(on 50Ω load), using 2 ranges. Pressing –20dB button will change the level range by
p-p
Range Lowest value Highest value Unit Resolution -20dB LED
1 10 1000 MV 1 Lighted
2 1.01 10.00 V 0.01 No light
Level is displayed on the second line of the LCD display, using a 4-digit value field, followed by the unit. The decimal point is used
only for the upper range. On the right of the second line, the word “Output” will be displayed to identify that the level parameter has
changed. Since the second line is used for displaying other parameters when they are modified, the unit will display the output level
again automatically 7 seconds after the last parameter modification,
Note: The level displayed on the LCD is considered a LOADED value which is the level that will appear across a 50Ω load connected
to the OUTPUT jack. If you are connecting the output to a high impedance load, the output voltage will be twice what is
entered.
Table2: Level ranges
3.1.3. Offset setting (except FREQCOUNTER mode).
This section describes the setting of the DC level added to the signal at the main output, OUTPUT jack.
Offset can be set between – 5.000 V and + 5.000 V (on 50Ω load), by turning the DC OFFSET knob and using 0.001V resolution (see
Table 3). The DC Offset LED associated to DC OFFSET knob will be lighted when the DC level added to the signal is not zero.
Offset is displayed on the second line of the LCD display using a sign digit and a 4-digit value field, followed by the measuring unit. On
the right of the second line the word “Offset will be displayed” to identify that the offset parameter has changed. Automatically, 7
seconds after the last change of the offset value, the unit will display the output level.
Note:
Range Lowest value Highest value Unit Resolution
1 - 5.000 + 5.000 V 0.001
1. The offset voltage specified is a 50Ω LOADED value. This is the voltage that will appear across a 50Ω load
connected to the OUTPUT jack. If the output is being connected to a high impedance load, the output voltage will
be twice what is entered.
2. Care must be taken when specifying an output offset voltage and level such that the output does not clip. The loaded
output cannot swing higher than + 5.000 V or lower than – 5.000 V. Therefore:
Table 3: Offset range
8
3.1.4. Duty cycle setting (except FREQCOUNTER mode).
This section describes the duty cycle setting of the signal outputted at the main output, OUTPUT jack.
Duty cycle can be set between 0% - 100%, by turning the DUTY CYCLE knob, using 1% resolution (see Table 4). The DUTY
CYCLE LED associated to DUTY CYCLE knob will be lighted when set duty cycle differs 50%, thus the signal on main output is
asymmetric.
Duty cycle is displayed on the second line of the LCD display, using a 3-digit value field, followed by the measuring unit. On the right
of the second line, the words “Duty Cycle” will be displayed to identify that the duty cycle parameter is shown. Automatically, 7
seconds after the last change of the duty cycle value, the unit will display the output level.
3.1.5. CMOS level setting (except FREQCOUNTER mode).
This section describes the level setting of the TTL/CMOS style signal outputted at the TTL/CMOS output jack.
Output level at the TTL/CMOS jack can be fixed or adjustable, depending on the TTL/CMOS button. The button enables/disables the
use of CMOS LEVEL knob.
If CMOS LEVEL knob is disabled, it will output a fixed level TTL style signal at 4.5V (unloaded). The TTL LED will be lit. The fixed
TTL level is displayed on the second line of the LCD display using a 2-digit value field followed by the measuring unit. The words
“TTL OUT” will be displayed on the right of the second line to identify that the TTL level is shown. The unit will display the output
level automatically 7 seconds after the last turning of CMOS LEVEL knob,
If CMOS LEVEL knob is enabled, the CMOS output level can be set between 4.0V and 14.0V (unloaded) by turning it using 0.1V
resolution (see Table 5). The CMOS LED will be lighted. The CMOS level is displayed on the second line of the LCD display using a
3-digit value field followed by the measuring unit. the words “CMOS OUT” will be displayed on the right of the second line to identify
that the CMOS level is shown. The unit will automatically display the output level 7 seconds after the last turning of CMOS LEVEL
knob.
Signal
Pressing this button will enable/disable the use of CMOS LEVEL knob. If enabled, the CMOS LED is lighted and the output level on
TTL/CMOS output jack can be changed. If disabled, the TTL LED is lighted and there is a fixed level on TTL/CMOS output jack.
| offset voltage | + ½ * V
Range Lowest value Highest value Unit Resolution
1 0 100 % 1
< 5.0 V
p-p
Table 4: Duty cycle range
Lowest value Highest value Unit Resolution LED lighted
TTL 4.5 4.5 V - TTL LED
CMOS 4.0 14.0 V 0.1 CMOS LED
Table 5: CMOS level range
3.1.6. Sweep time setting (only for INTERNAL SWEEP mode).
This section describes the sweep time setting of the signal outputted on OUTPUT jack when INTERNAL SWEEP mode is active
(INT LED and LIN/LOG LED are lighted).
Sweep time parameter represents the time needed by the unit to perform a frequency sweep between two frequencies, a start frequency
and a stop frequency. Sweep time can be set between 0.01 s and 30.00 s by turning the SWEEP TIME knob using a 0.01s resolution
(see Table 6).
Range Lowest value Highest value Unit Resolution
1 0.01 30.00 s 0.01
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Sweep time parameter is displayed on the second line of the LCD display using a 4-digit value field and a decimal point, followed by
the measuring unit. The words “Sweep Time” will be displayed on the right of the second line to identify that the sweep time parameter
is shown. The unit will automatically display the output level 7 seconds after the last change of the sweep time value.
Table 6: Sweep time range
3.1.7. Sweep width setting (only for INTERNAL SWEEP mode).
This section describes the sweep width setting of the signal outputted on the OUTPUT jack when INTERNAL SWEEP mode is active
(INT LED and LIN/LOG LED are lighted).
Frequency sweep is performed by changing the output frequency within a range. The start frequency is always greater than the stop
frequency. The start frequency setting is performed by turning the FREQUENCY knob. The stop frequency represents a fraction of the
start frequency; the fraction set by turning the SWEEP WIDTH knob. The sweep width value is not directly obtained by turning a
knob; we must calculate it using the formula:
where “value_SWEEP_WIDTH_knob” represents the value set by turning the SWEEP WIDTH knob.
The fraction of the start frequency can be set between 1 and 100 by turning SWEEP WIDTH knob, using 1-unit resolution (see Table
7).
Value Stop frequency Sweep width Resolution Observation
1 Start frequency 0 Lowest value
100 (Start frequency)/100 0.99*(start frequency)
Sweep width parameter is displayed on the second line of the LCD display using a 3-digit value field and a decimal point followed by
the measuring unit. The words “Sweep Width” will be displayed on the right of the second line to identify that the sweep width
parameter is shown. The unit will automatically display the output level 7 seconds after the last change of the sweep width value.
sweep_width = start_frequency * [1 – 1/(value_SWEEP_WIDTH_knob)] [Hz]
1
Table 7:
sweep
width calculation
Highest Value
3.1.8. Gate setting (only for FREQCOUNTER mode).
This section describes the gate period time setting used for measuring the signal frequency applied on COUNTER IN jack.
By pressing the range buttons, UP and DOWN, we can switch gate period time. There are 4 available period times for the gate: 0.01 s,
0.1 s, 1 s, and 10 s.
Gate period time is displayed on the second line of the LCD display. The mode identifier is displayed first, then the word “Counter”,
followed by the value of the gate period time.
3.2. Mode description
3.2.1. EXTERNAL VCG (External Voltage Control Generator).
This mode is used for generating an output waveform whose output frequency depends on the value set using the range buttons, the
FREQUENCY knob, and the external positive DC level applied on VCG SWEEP/COUNTER IN jack. The positive DC value applied
on VCG SWEEP/COUNTER IN jack will cause the output frequency to decrease proportionally, with a ratio between 1:1 and 1:100
(for DC value between 0.0 V and +10.0 V, respectively).
3.2.1.1. Selecting EXTERNAL VCG mode.
EXT LED lighting indicates active EXTERNAL VCG mode.
Otherwise there are 2 modes of selecting EXTERNAL VCG mode using front panel buttons depending on the current working mode
and the current value of SWEEP INT/EXT button.
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If in the INTERNAL SWEEP mode (INT LED lights), pressing the SWEEP INT/EXT button will engage the EXTERNAL VCG
mode. By engaging this mode, the EXT LED lights, and INT LED stops lighting.
If in the FREQCOUNTER mode (COUNTER LED lights), pressing the COUNTER/VCG SWEEP button will engage the mode
selected by the SWEEP INT/EXT button. If the button activates the INTERNAL SWEEP, the case will be the same as described in
the previous paragraph otherwise the button will activate EXTERNAL VCG mode.
3.2.1.2. Selecting output waveform.
Pressing one of the “WAVEFORM” buttons: SINE WAVE SELECT, SQUARE WAVE SELECT or TRIANGLE WAVE
SELECT, will engage one of the desired waveform: sine, square or triangle respectively. The current selected type of waveform will
have their corresponding LED lighted.
The shape of the waveform can be changed by modifying the duty cycle parameter (see example from section 3.2.5.4, where there are
displayed waveforms, with different duty cycle parameters).
3.2.1.3. Selecting the frequ en cy.
The output frequency can be set on the OUTPUT jack between 0.00Hz and 10.000MHz. See section 3.1.1 for details regarding setting
of the frequency value. This will also set the output frequency of the TTL/CMOS style signal outputted on TTL/CMOS jack.
To set certain frequency values it is preferable that the VCG/SWEEP input jack is disconnected from any source signal before pressing
the range buttons or turning the FREQUENCY knob. This way the VCG/SWEEP input jack does not affect the setting of the current
output frequency.
After setting the frequency using front panel controls, the selected output frequency can be modified by applying positive DC levels on
the VCG/SWEEP input jack. The DC levels must be within [0V, 10.0V] range, causing the output frequency to decrease with a ratio of
the original value with the ratio varying between 1:1 and 1:100, respectively.
ATTENTION: Appl
Applying certain positive DC levels on VCG/SWEEP jack will decrease the output frequency; the resulting fixed output frequency
represents a fraction of the original output frequency (see example 1).
Changing the DC level in a ramp style will cause a frequency sweep on the main signal output, the OUTPUT jack (see example from
section 3.2.5.1).
3.2.1.4. Selecting the level.
ying in excess DC levels above +10.0 V on VCG SWEEP input jack can damage the input.
The signal’s output level on OUTPUT jack can be set using the OUTPUT LEVEL knob between 10mV
regardless of the waveform type. See section 3.1.2 for details regarding setting of the level value (see example from section 3.2.5.1).
and 10.0V
p-p
(on 50Ω load),
p-p
The –20dB LED will be lighted if the –20dB attenuation is engaged on the main signal output path.
3.2.1.5. Selecting the offset .
The DC level added to the output signal on OUTPUT jack can be set using the DC OFFSET knob between – 5.000V and + 5.000V (on
50ohm load), regardless of the waveform type. See section 3.1.3 for details regarding setting of the offset value (see example from
section 3.2.5.1).
The DC OFFSET LED lights if the offset value is not 0.
3.2.1.6. Selecting the dut y cycle.
The duty cycle of the output signal on the OUTPUT jack can be set using the DUTY CYCLE knob, between 0% and 100%, regardless
of the waveform type. See section 3.1.4 for details regarding the setting of the offset value (see also examples 1, 2 and 3 on section
3.2.1.8).
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Attention:
The DUTY CYCLE LED lights when output signal is asymmetric.
See section 3.2.5.5 for waveform examples.
The square wave has the true meaning of duty cycle. By turning the DUTY CYCLE knob, the symmetry of the waveform
will change for the sine wave and triangle wave. For sine wave, a distorted wave shape will be obtained and for the
triangle wave, a ramp wave will be obtained.
3.2.1.7. Selecting output TTL/CMOS level.
The TTL/CMOS signal level can be changed using the TTL/CMOS button and CMOS LEVEL knob.
If CMOS output style is enabled, the output level can be set between + 4.0V and +14.0V, unloaded.
See section 3.1.5 for details regarding setting of the CMOS level (see also examples 1 and 2 on section 3.2.1.8).
3.2.2. INTERNAL SWEEP
This mode is used for outputting a signal on the OUTPUT jack that sweeps a frequency range. The output frequency does not depend
on any value applied on the input jack, VCG SWEEP/COUNTER IN.
3.2.2.1. Selecting INTERNAL SWEEP mode .
INT LED lighting indicates active INTERNAL SWEEP mode.
There are 2 modes of selecting INTERNAL SWEEP mode using the front panel buttons depending on the current working mode and
the current value of SWEEP INT/EXT button.
In EXTERNAL VCG mode (EXT LED lights), pressing the SWEEP INT/EXT button will engage the INTERNAL SWEEP mode.
By engaging this mode, the INT LED lights and EXT LED stops lighting.
In FREQCOUNTER mode (COUNTER LED lights), pressing COUNTER/VCG SWEEP button will engage the mode selected by
SWEEP INT/EXT button. If the button activates EXTERNAL VCG, the case is the same as described in the previous paragraph,
otherwise the button will activate the INTERNAL SWEEP mode.
3.2.2.2. Selecting output waveform.
Pressing one of the “WAVEFORM” buttons: SINE WAVE, SELECT, SQUARE WAVE SELECT or TRIANGLE WAVE
SELECT, will engage one of the desired waveform: sine, square or triangle respectively. The current selected type of waveform will
have their corresponding LED lighted.
The shape of the waveform can be changed by modifying the duty cycle parameter (see section 3.2.5.4, where there are displayed
waveforms for different duty cycle parameters).
3.2.2.3. Selecting the frequ en cy.
The sweep start frequency can be set directly on the OUTPUT jack using the range buttons and the FREQUENCY knob. Sweep start
frequency can be set between 0.00Hz and 10.000MHz (see section 3.1.1 for details regarding the setting of the frequency value).
The sweep stop frequency cannot be set directly. The SWEEP WIDTH knob must be turned in order to modify the sweep stop
frequency (see sections 3.1.7 and 3.2.1.9 for details).
Modifying any sweep parameter will restart the sweep with the new loaded parameters from the start frequency. Turning the
FREQUENCY knob will always display the sweep start frequency on LCD display (see section 3.2.5.2 for example of setting sweep
start frequency).
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