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PCH
09-02-2018, 01:49 PM
I hope that's the right term for them.

What I'm talking about is the little adaptors that you shove into a power outlet and out comes 12V DC 350mA etc.

I have a couple of cordless phones that use 9V DC 500mA adapters, and the phone seems to not be charging as it should. I've replaced the rechargeable battery so I know it's not that causing the problem, and it's still not charging sat in the cradle.

Next I thought to check the output of the adaptors. So I got my meter on it and expected to see about 9V show up. However, of the three 9V adaptors that I have, I get 12V, 14V and almost 20V.

Would I expect to see 9V out of a 9V adaptor? No laughing now, I'm serious ;)

Cheers

redbeard
09-02-2018, 02:13 PM
If the power supply is regulated then you would get 9v. Most are not and the voltages you see are normal. They would drop to 9v when under load.
Usually regulated ps units would mention it on the outside.

Cheers

PCH
09-02-2018, 02:18 PM
Thanks Damien, - that makes sense :)