There is a waveform only after connecting to a load. Internal schematic is shown below PWM Generator & Pulse Generator Frequency Duty Cycle Adjustable PWM Driver with Shell ZK-PP2K. - Two modes can be selected: PWM mode: frequency (continuous), duty cycle.
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ADF4351 Signal Source VFO Variable-Frequency Oscillator 5MHz to 4000MHz RF Frequency Counter Tester Meter Signal Generator
Aliexpress UK
Display: LCD1602 LCD English display. High frequency accuracy, frequency accuracy can reach 10 ~ 6 levels; high frequency resolution, full range frequency defense rate 10MHz. Infinite line restrictions, the full range of frequency regardless of gear, direct digital settings.
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FG-100 FG-200 DDS Function Signal Generator Frequency Counter 0.01Hz - 500KHz Signal Source Module Sine+Square+Sawtooth Waveform
Aliexpress UK
1 RF Noise Signal Generator. Frequency range:0.2-2000MHz.
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Portable TinySA Spectrum Analyzer Upgraded V0.3.1 Tiny Frequency Analyzer 100kHz to 960MHz MF/HF/VHF UHF Input Signal Generator
Aliexpress UK
High frequency accuracy, frequency accuracy can reach 10 ~ 6 levels; high frequency resolution, full range frequency defense rate 10MHz. Infinite line restrictions, the full range of frequency regardless of gear, direct digital settings.
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XR2206 High Precision Function Signal Generator DIY Kit Sine Triangle Square Output 1Hz-1MHz Adjustable Frequency Amplitude
Aliexpress UK
35MHz-4400MHz RF signal generator ADF4351 module sweep generator PLL with for OLED display. The module can realize frequency output of 35MHz-4.4GHz, basic functions such as point frequency, frequency sweep, and frequency hopping.
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High-Precision XR2206 Signal Generator Kit - 1Hz to 1MHz Adjustable Frequency, Sine/Triangular/Square Wave Output (DIY Build)
Aliexpress UK
Frequency: 1Hz -1MHz. Flatness: +0.05DB 1Hz -100kHz. It can produce sine waves, triangular waves, Square waves. WaveForms: Square, Sine & Triangle. Sine wave：. Triangle wave：. 1 XR2206 High - for precision signal generator.
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XR2206 High Precision Function Signal Generator DIY Kit Sine Triangle Square Output 1Hz-1MHz Adjustable Frequency Amplitude
Aliexpress UK
Scanning : linear scanning, pairing scanning. High frequency accuracy, frequency accuracy can reach 10 ~ 6 levels; high frequency resolution, full range frequency defense rate 10MHz. Infinite line restrictions, the full range of frequency regardless of gear, direct digital settings.
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JDS6600 15/30/40/50/60MHz DDS Function Signal Generator/Source Dual/2-CH Frequency Meter Arbitrary Waveform Pulse Generator
Aliexpress UK
High frequency accuracy, frequency accuracy can reach 10 ~ 6 levels; high frequency resolution, full range frequency defense rate 10MHz. Scanning : linear scanning, pairing scanning. Infinite line restrictions, the full range of frequency regardless of gear, direct digital settings.
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NE555 Pulse Generator Pulse Starter Duty Cycle and Frequency Adjustable Module DIY Kit Oscillator Square Wave Signal Generator
Aliexpress UK