Signal Generators: Principles, Brands,Operation Guides, and Troubleshooting

Signal Generators: Principles, Operation Guides, and Troubleshooting

I. Overview

Signal generators, also known as signal sources or oscillators, are devices capable of producing various waveforms, frequencies, and amplitudes of electronic signals. They play a crucial role in the field of electronic technology, widely used in testing, calibration, and experimentation. By simulating the excitation signals required by devices under test in real-world environments, signal generators assist engineers and technicians in accurately measuring and analyzing the performance parameters of electronic circuits and equipment.

II. Principles

[Image 2: Principles of Signal Generators]

The working principle of signal generators is based on oscillator theory, which generates stable electronic signals through internal circuit oscillations. Specifically, signal generators produce a reference frequency through a signal source (such as a crystal oscillator or reference signal). This frequency is then adjusted in terms of output signal frequency and amplitude through frequency control circuits and amplitude control circuits. Different types of signal generators may employ various oscillation circuits and modulation techniques to produce signals of specific waveforms. For example, sine wave signal generators typically utilize RC or LC oscillation circuits, while pulse signal generators may leverage gate circuits or switching circuits to generate pulse signals.

III. Operation Methods

1. Power Connection: First, connect the signal generator to an appropriate power source and ensure a stable connection.
2. Parameter Setting: Set the output signal type (e.g., sine wave, square wave, pulse wave), frequency, amplitude, and phase of the signal generator as needed, using knobs, keyboard inputs, or menu options.
3. Output Connection: Connect the output port of the signal generator to the device or measurement system under test, ensuring correct connection.
4. Calibration and Verification: Before formal testing, calibrate and verify the signal generator to ensure the accuracy and stability of the output signal.
5. Testing Initiation: Start the signal generator to produce the required signal and proceed with experimentation, testing, or debugging.
6. Output Monitoring: Use appropriate measurement equipment (e.g., oscilloscopes, spectrum analyzers) to monitor the output signal of the signal generator, checking parameters such as frequency, amplitude, waveform, and stability for consistency with expectations.
7. Parameter Adjustment: Adjust the parameters of the signal generator as needed to meet specific testing requirements or application needs.
8. Testing Completion: After testing, stop the signal generator and gradually disconnect it from the test equipment or measurement system.

IV. Troubleshooting and Repair Methods

[Image 4: Troubleshooting and Repair Methods]

1. Power Issues: Power failures are common in signal generators. Check for secure power cord connections and normal power supply. Replace the power cord or faulty power supply if necessary.
2. Display Issues: If the display is unreadable, unstable, or shows incorrect content, it may be due to display screen failure, display driver circuit failure, or system firmware issues. Check for secure display connections, restart the device, update firmware, or replace the display screen.
3. Output Issues: Unstable output signal amplitude, incorrect frequency, or waveform distortion may result from output circuit failure, clock synchronization issues, or interference from external sources. Check output circuit connections, inspect clock synchronization circuits, and eliminate interference sources.
4. Control Issues: Malfunctioning control buttons or inaccurate adjustments may be caused by control circuit failure, control software issues, or faulty buttons. Check control circuit connections, restart the device, update software, or replace buttons.
5. Connection Issues: Loose connections, poor contact, or line failures between the signal generator and the device under test can lead to abnormal test signal output. Ensure secure connections, reinsert connection cables, and repair line failures.
6. Calibration Issues: An improperly calibrated signal generator can result in output errors, frequency deviations, or amplitude distortions. Perform regular calibration and adjust parameters and signal sources according to calibration requirements to ensure accurate output.
7. Cooling Issues: Signal generators generate heat during operation and require an effective cooling system. Cooling system failures can lead to device overheating, affecting performance and lifespan. Check for properly functioning cooling fans, clean ventilation holes, and ensure a smooth cooling system.
8. Noise Issues: Noise in the output signal can affect the accuracy of test results. Check for interference in signal source input and output lines, and add shielding and filters to eliminate noise.

In summary, signal generators are vital equipment in the field of electronic testing, and their principles, operation methods, and troubleshooting methods are crucial for ensuring test accuracy and device reliability. By operating and maintaining signal generators correctly, their important role in the field of electronic technology can be fully leveraged.

V. Brands and Models of Signal Generators Repaired by Longi Electromechanical

1. Keysight Technologies
   • MXG X-Series: N5181B (Analog), N5182B (Vector)
   • EXG X-Series: N5171B (Analog), N5172B (Vector)
   • UXG X-Series: N5193A (Vector)
2. Rohde & Schwarz
   • SMW200A: High-Performance Vector Signal Generator
   • SMB100A: Analog Signal Generator
   • SMA100B: High-Performance Analog Signal Generator
   • SGT100A: Vector Signal Generator
3. Tektronix
   • AWG70000 Series: AWG70001B, AWG70002B
   • AFG31000 Series: AFG31151, AFG31251
4. Anritsu
   • MG3690C Series: MG3691C, MG3692C, MG3693C
   • MG3710E: Vector Signal Generator
5. National Instruments (NI)
   • PXIe-5451: Vector Signal Generator
   • PXIe-5653: Vector Signal Generator
6. Signal Hound
   • USB-SG44: USB Vector Signal Generator
   • USB-SG44A: High-Performance USB Vector Signal Generator
7. B&K Precision
   • 4050B Series: 4051B, 4052B, 4053B
8. Rigol Technologies
   • DSG800 Series: DSG815, DSG830
   • DSG3000 Series: DSG3060, DSG3030
9. Stanford Research Systems (SRS)
   • SG380 Series: SG382, SG384
10. Tabor Electronics
    • WW1071: High-Performance Arbitrary Waveform Signal Generator
    • WX2184C: High-Speed Arbitrary Waveform Signal Generator
11. Aim-TTi
    • TGR2051: General-Purpose Signal Generator
    • TGR2050: High-Performance Signal Generator
12. Boonton
    • SGX1000 Series: SGX1003, SGX1006
13. Marconi Instruments
    • 2024: General-Purpose Signal Generator
    • 2031: High-Performance Signal Generator
14. Aeroflex / IFR
    • 2025: General-Purpose Signal Generator
    • 3410 Series: 3410, 3412
15. Agilent: E4421B/E4421A/E4422B/E4422A

Longi Electromechanical has nearly 30 years of experience in repairing signal generators and can quickly repair various types of instruments. Additionally, we recycle and sell various signal generators. Welcome to consult.