Meter frequency measurement module

[electronium]

Hello guys, I hope you are doing well
Is it possible to measure city electricity frequency and pwm peak of power transistor with this module? How is it possible?

[TizianoHV]

Hi,
this "DIY Digital LED Frequency Counter 1Hz-50MHz USB 5V Crystal Oscillator Meter Tester Kit" is not able to measure directly mains voltage (max 5V). You'll need a step down transformer and probably a voltage divider.
If you search online you can find cheap 220V-12Vac lamps transformers and add a voltage divider to step down 12VAC to around 1.5VAC (2.2k / 220R). Or you can use one ZMPT101B module (https://it.aliexpress.com/item/32810872584.html?spm=a2g0o.productlist.main.1.235d72f1KsgXg1&algo_pvid=5cedd623-1aa3-43be-aafb-4a6810c65149&algo_exp_id=5cedd623-1aa3-43be-aafb-4a6810c65149-0&pdp_npi=4%40dis%21EUR%211.29%211.29%21%21%211.38%21%21%402103853f17030696575861289e8150%2110000000419948036%21sea%21IT%213408016261%21&curPageLogUid=pECiFK0w13YZ) and regulate it to the correct voltage. Before connecting to mains put everything in a box to avoid touching mains.

What do you mean with "pwm peak of power transistor"?