Circuitrocks

<t>Daily-driver pa rin Fluke 117 sa shop. Hindi ko maipakita yung pera difference sa customer, pero yung peace of mind when probing a board na hindi mo alam yung max voltage, walang katumbas.<br/>
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Yung Aneng AN-870 yung dressier-than-it-deserves cheap option. PHP 1200, 4-1/2 digit, true RMS ...

<r>Common repair: lifted pad from rough rework. Customer brings phone or board, pad torn off, trace exposed. Throw-away rate dropping kasi here is how I save 70% of them.<br/>
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<B><s>[b]</s>Tools:<e>[/b]</e></B> flux paste, fine kynar wire (30AWG), hot air at 280C, microscope (or 10x loupe), UV ...

<r>Sharing yung patterns na nakita ko sa shop. Cheap phone chargers and small wall warts ang pinaka-common na PSU failures we get.<br/>
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<B><s>[b]</s>Top 3 failure modes (most to least common):<e>[/b]</e></B><br/>
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<B><s>[b]</s>1. Capacitor failure<e>[/b]</e></B>, yung mga electrolytic ...

<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 ...