Another Troubling Area
If you thought the taping flaw was bad, just wait: the secondary winding goes all the way to the primary side’s terminals where a nearly identical story repeats. Multiple bulges in the primary winding caused the secondary’s turns to slip to the sides. A particularly large bulge near the end caused the secondary’s top turn to butt up against the primary winding’s wire. In a properly made transformer, this part of the wire would be sleeved or otherwise double-insulated to prevent such manufacturing flaws from becoming an issue.
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Are Counterfeit A1265 Adapters A Good Investment?
Regardless of how convenient sub-$2 adapters might be, I cannot think of any good reason to recommend these death traps. If you do use one, treat whatever you plug into it as bare wire mains voltage.
The good?
- Shouldn’t fall apart accidentally
- Surprisingly fault-tolerant
The Bad?
- Can barely provide 500mA at 115VAC and 750mA at 230VAC
- Output ripple + noise in excess of 600mV at best
- Poor output voltage regulation against load and AC input voltage
The Ugly?
- No isolation slots to keep low voltage and high voltage separate
- Isolation failure at the USB shield at merely 1kVAC
- Non-Y-class EMI suppression capacitor failed at 1875V
- MULTIPLE TRIVIAL YET POTENTIALLY LETHAL TRANSFORMER MANUFACTURING FLAWS
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