Thursday, November 01, 2012
A quick scan of the headlines in my Lifehacker feed this morning reminded me of an article I encountered by accident a week or so ago. This was a couple of days after I'd noticed bizarre, random
"dialing" behavior on my smartphone upon attempting to charge it one evening with the AC charger from a phone charging kit I'd received as a gift.
Whitson Gordon sums up the problems that off-brand phone chargers can pose:
The short version of his findings: Official chargers are the best, off-brand chargers from manufacturers like Belkin and KMS are okay, and knockoffs are a $2 safety hazard. If you're looking to buy an official charger from Apple or Samsung, buy it directly from them to make sure you don't get a knockoff. And, if you're trying to save a few bucks by buying a third-party charger, just know that it's a clear case of "you get what you pay for" (though our favorite cheap cable retailer, Monoprice, seemed to be an exception to that rule).Ken Shiriff reports the following, after testing a variety of chargers. I think this is likely what is wrong with the AC charger in my set. (The set also comes with a 12 V DC charger, which exhibited no such problems when I was using it.)
A poor design can suffer several problems. If the output voltage is not filtered well, there will be noise and spikes due to the high-frequency switching. At extreme levels this could damage your phone, but the most common symptom is the touchscreen doesn't work while the charger is plugged in...During charging, my problem manifested as random numbers appearing on my login screen without my doing anything, as well as my own inability to provide input. I initially guessed that I had a bad USB cable. This turned out to be a problem with the set, but swapping in another cable did not make the problem disappear. Thinking I had a problem with the phone or the software -- All USB chargers are the same, right? -- a few Internet searches left me scratching my head and adopting a wait-and-see attitude. After I ran into Shiriff's article, I quickly confirmed that the problem was nonexistent with my phone's regular charger, but returned with the other charger. (I also learned that the charger's USB cable was defective, too, and discarded it.)
My thanks to Ken Shiriff to sharing his enthusiasm for electronic devices and his expertise. He lifted a minor cloud of doubt about my phone from my mind and possibly kept me from damaging it with a bad charger.