EEVblog #1020 - Is A $7 LCR / Component Tester Any Good?
Why Electrical Engineering Stack Exchange recommends it
Electronics Stack Exchange answerers link it as proof that cheap LCR/component testers can identify unmarked parts and measure capacitance and MOSFET pinouts.
Recommended by 2 people across 2 different months, 2019 to 2022.
What it is
Dave Jones of EEVblog tests a roughly $7 eBay M328 (LCR-T4) component tester, checking how well it identifies parts and measures values. He also points to the large forum thread and the community-maintained AVR Transistortester firmware.
What people said
Recommends Harry Svensson · 2019-01 · Electrical Engineering Stack Exchange · on “How can you conduct a simple test for a MOSFET?”
You could... change your question to include a minimalistic circuit. Or just get a cheap multimeter [this video] . Notice how all 3 terminals are being connected in the link, and then measured internally of the multimeter in some simple circuit. Not 2, but 3. - I want to correct my earlier metaphor, I said 3D-model => 2D. It's actually more like 3D-model => 1D, because the current is the same at the 2-terminals. Again, this is just a metaphor. Trying to make you understand that you are throwing away an absurd amount of information trying to only do it with 2 terminals.
Recommends MicroservicesOnDDD · 2022-01 · Electrical Engineering Stack Exchange · on “How do I identify SMD components? (or how do I identify any component)”
Device Opportunity I am about to tout a device which true Electrical Engineers will be tempted to look at with suspicion, primarily because it's so inexpensive. Or because it's Open-Source Hardware (OSHW). But it's actually not cheap. It may be composed of cheap components, and cheap materials. But it's full of blood, sweat, and tears. And because it's OSHW, and I can examine the hardware, the firmware, upgrade it, fix it, and enhance it, that's worth it's weight in gold to me. But it also represents a financial opportunity, since there's an obvious hole here (there is no other product like it). Can you fill that hole? Perhaps you'll make money if you make your own closed-source solution. Or
Cites Dave Tweed · 2019-07 · Electrical Engineering Stack Exchange · on “Replacing a missing capacitor”
Since capacitors are not typically marked, the only way to find the value is to measure them. You'll have to get a meter that can measure capacitance 1 , take the corresponding capacitor off of the good board, measure its value, and then purchase a replacement that's the same size and value. Solder both capacitors back onto their respective boards. BTW, even without a scale for measurement, that looks a lot more like 0805 to me than 1206. 1 There are plenty of cheap LCR tester kits [this video] on the market that can do this.