Circuitrocks

<t>Customer brought in a project last week — claims his 5V regulator is "fluctuating". Showed me his multimeter reading 4.9V → 5.2V → 4.7V randomly. Naka-charged yung battery ng meter, decent unit (Fluke 17B+).<br/>
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Nag-probe ako with my own scope side by side. Scope: rock-stable 5.00V flat ...

Electronics tech, repair shop owner. Mostly phone and gadget repairs ngayon pero side passion ko yung older equipment — solving the weird stuff na walang school nagtuturo. May tendency akong mag-share ng failure modes na natutunan ko sa shop. Hindi ako nag-sugarcoat. Pero willing mag-help.

<t>Confirming this from the shop side — about half ng "ESP32 not working" customers namin are brownout-from-USB issues. Yung other half are CH340 driver or counterfeit boards.<br/>
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Trick na natutunan ko: probe yung 3.3V rail with an oscilloscope habang nag-bo-boot at nagco-connect sa WiFi yung ...

<r>For ferrite rods, try these in order:<br/>

<LIST><s>[list]</s>
<LI><s>[*]</s><B><s>[b]</s>Deeco Surplus<e>[/b]</e></B> sa Quiapo, second floor — may section pa rin ng older AM/FM components. Dalhin mo yung sirang isa for size reference.</LI>
<LI><s>[*]</s><B><s>[b]</s>Alexan along Raon<e>[/b]</e ...

<t>+1 sa watchdog. Pasok din sa shop yung mga IoT board na "biglang patay" — usually USB regulator failure from voltage spikes, hindi naman firmware crash. Add a TVS diode sa USB rail kung deployment is unattended. Mga PHP 5 lang yung diode, sasalbahin ka sa repeat trips.<br/>
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Power supply ...