B&K 4070A User Manual

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User’s Manual

Model 4070A

21.5MHz Multi Function Arbitrary Waveform Generator

B&K Precision

Model 4070A

User’s Manual

B+K Precision Corp.

ALL RIGHTS RESERVED

PRODUCT AND DOCUMENTATION NOTICE: B+K Precision reserves the right to change this product and its documentation without prior notice.

Information furnished by B+K Precision is believed to be accurate and reliable. However, B+K Precision assumes no responsibility for its use, nor for any infringement of patents, or other rights of third parties, which may result from its use. No license is granted by implication or otherwise under the patent rights of B+K Precision.

PRINTED IN U.S.A.

Printing History

Second Edition 12/2002

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

B+K Precision Corp.

Tel: (714)921-9095Internet: http://www.bkprecision.com

28820 Savi Ranch Parkway

Fax: (714)921-6422

Yorba Linda, CA 92887-4604

 

____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

 

Table of Contents

 

1.0 Introduction

 

1.1 Description ..................................................................................................................................................................

2

1.2 Feature summary .........................................................................................................................................................

3

2.0 Installation and setup

 

Detail explanation of input and output connectors .......................................................................................................

4

3.0 Operating controls and keys

 

3.1

Mode key...................................................................................................................................................................

8

3.2

Field arrow keys........................................................................................................................................................

8

3.3

Store/Recall key ........................................................................................................................................................

8

3.4

Offset key...................................................................................................................................................................

8

3.5

Trigger key.................................................................................................................................................................

9

3.6

Numeric keys (0 to 9, -.) .........................................................................................................................................

9

3.7

é,ê,è,ç keys ....................................................................................................................................................

9

3.8

Clear key.....................................................................................................................................................................

10

3.9

MHz/dBm, KHz/Vp -p/Sec,Hz/mVp-p/mSkeys....................................................................................................

10

3.10 One Touch Mode keys............................................................................................................................................

10

4.0 Operating guide.

 

4.1 Changing frequency...................................................................................................................................................

11

4.2 Changing level............................................................................................................................................................

11

4.3 Changing operating modes .......................................................................................................................................

11

4.4 Operating mode selections........................................................................................................................................

11

4.5 Changing values .........................................................................................................................................................

12

4.3.1 Modifying an existing value ..................................................................................................................................

12

4.3.2 Entering a new value...............................................................................................................................................

12

5.0 Mode descriptions

 

5.1 Basic Sinewave (CW) mode.....................................................................................................................................

13

5.2

Internal AM mode.....................................................................................................................................................

14

5.3

External AM mode.....................................................................................................................................................

15

5.4

Internal FM mode......................................................................................................................................................

16

5.5

External FM mode......................................................................................................................................................

17

5.6

Internal PM mode......................................................................................................................................................

18

5.7

External PM mode......................................................................................................................................................

19

5.8

Sweep mode ...............................................................................................................................................................

20

5.9

Internal FSK mode.....................................................................................................................................................

22

5.10 External FSK mode ....................................................................................................................................................

23

5.11 Burst mode ................................................................................................................................................................

24

5.12 Internal SSB mode....................................................................................................................................................

25

5.13 External SSB mode....................................................................................................................................................

26

5.16 DTMF Generation mode..........................................................................................................................................

27

5.17 DTMF Detection mode............................................................................................................................................

29

5.18 Power & Voltage Measurement mode...................................................................................................................

30

5.19 Arbitrary mode..........................................................................................................................................................

31

5.20 Remote mode.............................................................................................................................................................

31

5.21 Other mode................................................................................................................................................................

31

5.22 Internal BPSK mode.................................................................................................................................................

32

5.23 External BPSK mode.................................................................................................................................................

33

5.24 Dual tone Generation mode ....................................................................................................................................

34

5.25 Data Modulation mode............................................................................................................................................

36

5.26 Voltage Controlled Oscillator (VCO) mode...........................................................................................................

39

6.0 Remote operation

 

6.1

Introduction..................................................................................................................................................................

40

6.2 Hookup..........................................................................................................................................................................

40

6.3

Checking your connection with Hyper Terminal....................................................................................................

40

6.4

Operation ......................................................................................................................................................................

41

6.5 Programming Rules......................................................................................................................................................

41

6.6 Remote control command List...................................................................................................................................

42

6.7 Examples........................................................................................................................................................................

45

7.0 Arbitrary waveform system

 

7.1 Arbitrary Waveform Quick Start Guide....................................................................................................................

46

7.2

Introduction to the Arbitrary Waveform Generator

 

7.2.1 Description of the Arbitrary Waveform System..................................................................................................

47

7.2.2 Feature Summary ......................................................................................................................................................

48

7.3

Switching to the Arbitrary/Function/Pulse Generator Modes .............................................................................

48

7.4 Arbitrary Waveform Mode ........................................................................................................................................

49

7.5

Function Generator Mode..........................................................................................................................................

50

7.6

Pulse Generator Mode ................................................................................................................................................

51

7.7 Downloading Arbitrary Waveforms

 

7.7.1 Using WAVELOAD.EXE........................................................................................................................................

52

7.7.2 Using your own program.........................................................................................................................................

53

7.8 Arbitrary Waveform Data Formats

 

7.8.1 Floating Point Format...............................................................................................................................................

54

7.8.2 Time & Value Floating Point Format (.CSV, .PRN) ..............................................................................................

55

7.8.3 Digital Format............................................................................................................................................................

56

7.8.4 Integer Format...........................................................................................................................................................

57

7.8.5 Hexadecimal Format..................................................................................................................................................

58

7.8.6 Binary Format............................................................................................................................................................

59

7.9

Multiple Units Locking

 

7.9.1 Introduction and Hookup........................................................................................................................................

60

7.10 Example Arbitration Program ARB.BAS................................................................................................................

62

8.0 DC Operation Option

 

8.1

Specifications and hookup.........................................................................................................................................

69

9.0 Specifications.....................................................................................................................................................

70

10.0 Software CD

 

10.1 Contents of the accompanying disk.......................................................................................................................

71

Appendix A

Appendix B

RS-232remote control example host program.....................................................................................

72

Application example: Television remote control................................................................................

77

Warranty information

......................................................................................................................................81

1.0 Introduction

Figure 1.0-1:The BK Precision model 4070A

This manual contains operating instructions for the BK Precision Model 4070A Signal Generation and Processing Engine. Complete specifications for the Model 4070A are given in Chapter 9.

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BK Precision 4070A User Manual Rev.2.2

1.1 Description

Figure 1.1-1:4070A front panel

The Model 4070A is a versatile signal source capable of generating a variety of waveforms, including CW and wideband sweeps from D.C. to 21.5 MHz in steps of .01 Hz. The signals are generated using direct digital waveform synthesis (DDS) techniques for high accuracy and precision. AM, FM, PM, and FSK modulation types are available. A high speed Digital Signal Processor (DSP) controls every aspect of the DDS system and is used internally for the precise generation and processing of all modulating waveforms. DSP technology in 4070A allowed implementing additional modes to analyzes an externally applied signal such as DTMF detection and power level measurement.

The 4070A is designed to supply an output signal level of 20.0 Vp -pwith an offset voltage of +/- 6.0V. The output impedance is 50O; therefore the 50O loaded output level is 10.0 Vp-p,with an offset voltage capability of +/- 6.0V. The output level and offset voltages can be adjusted with a resolution of 1 mV. Output levels can also be specified in dBm with 0.1dBm resolution.

The front panel, shown in figure 1.1-1,has two output connectors. The SIG Out connector is the main signal output. The SYNC Out connector is a TTL/CMOS compatible square wave output. It is a "hard limited" version of the main output and is available in all modes. The SYNC Output is signal +5V and is useful for driving digital circuitry.

The front panel of the Model 4070A includes a full numeric keypad and rotary knob to allow quick adjustment of any numeric value and gives the user the ability to manually adjust a value across a wide range.

The LCD display is a large 2 line by 40-columndisplay with backlight. It is large enough to display all operating parameters simultaneously and thus eliminate tedious submenus.

The user can select a modulating waveform that is either internally generated or externally supplied. External signals in the DC to 35 KHz range could be used for 4070A external modulation. External modulation connector is located on the back of the unit. This input is high impedance (about 30KO) to avoid loading the source of the signal.

The unit also features an external digital input, located on the back of the unit, which serves several purposes depending on the mode. For most modes, it serves as a gate to switch the RF output signal on and off. In external FSK or BPSK mode, it is a high-speeddata input for FSK or BPSK digital modulation of the output waveform at rates up to 3 MHz. In modes that have a trigger function (Burst, Triggered Sweep, etc.) this input serves as an external trigger which triggers a sweep or burst on the rising edge of the input.

The unit also features an RS232 connector on the back panel of the unit. This permits the user to remotely control the 4070A using ASCII characters. No special hardware or protocols are needed; any dumb terminal or computer serial port can be used. On-linehelp menu that lists all remote control commands to the terminal is available. The baud rate is adjustable up to 115.2 Kbps. Software upgrades are also downloaded to internal Flash memory using this port.

An Arbitrary Waveform Generator lets the user design custom waveforms on a PC and downloads them to the 4070A for generation. Up to 32,768 unique points may be specified and generated by a 12 bit DAC with a sampling adjustable from 0 Hz to 40 MHz in .01 Hz steps. A logic waveform may also be generated simultaneously with the analog waveform. The unit will accept many popular data formats for maximum flexibility. Arbitrary Waveforms may be conveniently saved to nonvolatile memory.

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BK Precision 4070A User Manual Rev.2.2

Included with the Arbitrary Waveform Generator is a full featured Function Generator and Pulse Generator. The function generator offers a set of pre -storedwaveforms, which are generated using the Arbitrary Waveform system. The Pulse Generator allows the user to generate pulse waveforms with varying amplitude, offset, frequency and duty cycle.

1.2 Feature summary

Each unit is individually calibrated to ensure accurate output frequency, level, and offset voltage.

Output level: 4mVp -pto 20Vp-p(unloaded). Output level can be entered with 1 mV or .1 dBm resolution.

Output offset: 0 mV to +/- 6.0 V. Output offset can be entered with 1 mV resolution.

TTL/CMOS compatible logic output drives digital circuits directly.

Flash Memory is used for code storage to enable easy software updates.

10 complete instrument setups can be individually stored or recalled.

Unit has a large, easy-to-readilluminated LCD display, which shows all operating parameters for each setup. No confusing submenus.

Full numeric keypad and rotary encoder make entering and adjusting parameter values easy.

Standard RS232 port included. Remote control operation requires no special hardware or software. Baud rate is programmable. All commands use ASCII characters. Programming examples are included.

External modulation input is wideband: DC to 35 KHz. High input impedance (30K O avoids loading the source signal.

External logic input allows user to gate output signal on/off under logic control. It can also be used as an external trigger signal.

External FSK and BPSK data is also brought in on this connector.

Modes

∙ Basic Sinewave

∙ DTMF Generation

∙ Internal/External AM

∙ DTMF Detection

∙ Internal/External FM

∙ Voltage & Power Measurement

∙ Internal/External PM

∙ Burst (Continuous or Int/Ext trig)

∙ Internal/External SSB

∙ Sweep

∙ Internal/External BPSK

(Linear/Log/Continuous/Triggered/Up/Down)

∙ Internal/External FSK

∙ Dualtone Generation

∙ Data Modulation

∙ Voltage Controlled Oscillator (VCO)

Options (contact factory for availability):

 

High stability time-base

DC Operation

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BK Precision 4070A User Manual Rev.2.2

2.0 Installation and setup.

This section discusses how to properly connect the 4070A to your equipment. The following diagrams identify the connectors and show typical hookups.

Figure 2.0-1:Front Panel Connectors

1. SYNC out connector

This connector provides a TTL/CMOS signal, +5V logic level useful for driving digital circuitry. This output is capable of driving TTL or CMOS loads with current capability +/- 24 mA.

In all sinewave and modulation modes except sweep, this connector supplies squarewave version of the signal on the SIG Out connector. It has a fixed 50% duty cycle.

In the Sweep mode, this connector provides a high going pulse at the beginning of each sweep.

In the Arbitrary Waveform Generator mode, the user may set this output high or low on any data point(s) in the Arbitrary Waveform. This feature could be used to create a pattern of logic pulses or a triggering or synchronizing signal, which accompanies an analog waveform.

In the Function Generator mode, a high going pulse is given on this output at the start of each function waveform. This useful feature allows the user to synchronize the functions to other events.

In the Pulse Generator mode, this output follows the SIG Out signal. The signal on this output has the same frequency and duty cycle as signal on the SIG out connector. However the signal on this connector is not variable in amplitude and offset; it set to +5V, to provide a convenient interface with TTL/CMOS digital logic.

2. SIG Out connector

This is the main signal output. It has a source impedance of 50? , and can supply signals as large as 20 Vp -pinto an open circuit or 10Vp-pinto a 50O load. It can also supply a DC offset voltage of +/- 6.0V into a 50O load.

*** Caution ***

Although the output is protected against short circuits, you should NEVER connect SIG Out to a voltage or signal source. This may overload the output and damage the 4070A.

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BK Precision 4070A User Manual Rev.2.2

3. External Modulation In connector

The External Modulation In connector, located on the rear of the 4070A, accepts an external analog signal as illustrated here:

Figure 2.0-3:Connecting an external signal

On this connector, the user supplies a base band signal (below 50 KHz) that is used to modulate an output carrier. (microphone is shown here as an example). It also serves as the input connector for DTMF signals in DTMF Detection mode, and signals to be measured in the Power Level and Voltage Measurement mode.

This input is high impedance (about 30KO). It was made high impedance to avoid loading down the circuit supplying the signal.

This input is DC coupled within the 4070A. The signal on this input is internally low pass filtered to a cutoff frequency of 50KHz.

The input level for this connector is ±5V max. For external modulation modes, a 1Vp-psignal will fully modulate the carrier. If you apply ahigher-levelsignal than 1 Vp-p,the input signal will be distorted. The distortion that will take place under these conditions is a "hard limiting" type (i.e. the waveform will "flat top" at the positive and negative extremes). Under these conditions, the word "Overld" will be printed to the LCD for input levels that are too high.

*** Caution ***

External signals greater then ±25Vp-prange on external applied to modulation input may damage the 4070A.

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BK Precision 4070A User Manual Rev.2.2