NE555 Pulse Generator Pulse Starter Duty Cycle and Frequency Adjustable Module DIY Kit Oscillator
Aliexpress UK
The product can not only output 7.83Hz Schumann wave, but also can be adjusted in the range of 0.1Hz ~ 100KHz frequency, digital circuit crystal oscillator frequency reference, more stable, stronger anti-interference.
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NE555 Pulse Generator Pulse Starter Duty Cycle and Frequency Adjustable Module DIY Kit Oscillator
Aliexpress UK
The product can not only output 7.83Hz Schumann wave, but also can be adjusted in the range of 0.1Hz ~ 100KHz frequency, digital circuit crystal oscillator frequency reference, more stable, stronger anti-interference.
eBay
DC 4.2-9V to10-20KV 10W High Voltage Pulse Generator Super Arc Pulse Ignition Coil Module Power
Aliexpress UK
Powers on but no further testing done.
eBay
AC 220V High Voltage Generator Module Continuous Igniter Pulse Generator Inverter Board for Power
Aliexpress UK
Output with LED indication(low level ,LED will on; high level,LED will off;low frequency, the LED flashes);. Adjustable pulse for the use of MCU. M-H frequency: C=0.1UF; High frequency: C=0.001UF. Output amplitude: 4.2V V-PP to 11.4V V-PP.
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DC6-12V NE555 Pulse Generator Module Sine/Triangle/Square Wave Generator Multi-Channel Waveform
Aliexpress UK
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High Voltage Generator DC 3.7V-7.4V to 1000kV Boost Step-Up Inverter Arc Pulse Generator Power
Aliexpress UK
Overall good condition.
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1/5/10PCS DC 5V 12V NE555 Adjustable Resistance Frequency Pulse Generator Module Single Channel
Aliexpress UK
The product can not only output 7.83Hz Schumann wave, but also can be adjusted in the range of 0.1Hz ~ 30KHz frequency, digital circuit crystal oscillator frequency reference, more stable, stronger anti-interference.
eBay
10/50Pcs NE555 NE555N 555 NE555DR NE555DT SMD Precision Timers IC Chip SOP-8 New for Pulse Generator
Aliexpress UK
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