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Registered Member #2431
Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639
there is a whole lot that goes into ESR and stray factors like inductance --- thickness of the aluminum, width versus length, electrolyte, purity ofaluminum, diameter of the output terminal and so on, its not just the electrolyte.
and theres a lot of competition to get to the low numbers among cap makers, so im sure they'res espianoge afoot.
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4059
I wonder if you can detect "badCaps" (tm) using the magnetic sensor on a mobile phone with an induction based hysteresis loop generator running off the headphone output?
Registered Member #2431
Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639
Conundrum wrote ...
I wonder if you can detect "badCaps" (tm) using the magnetic sensor on a mobile phone with an induction based hysteresis loop generator running off the headphone output?
well now that you blurt it out, you wont be able to patent it...
Registered Member #96
Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4059
Yep, it uses the weak electromagnetic signature from say the analogue clock or phone speaker etc. It can also detect the differential absorption of say C-4 compared with inert materials.
Turns out that even a dead mobile phone can be located this way, and it is also possible to hack an SDR such as the one found in some DTV sticks into a primitive yet effective scanner for bugs by sweeping the EM spectrum and looking for a harmonic.
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Motherboard capacitor voltage tolerances.
