electrical question

mufc802 · 8 Jan 2011 at 19:06

I've bought a radio kit which requires a 12v/100mA power supply but it didn't come with one. I was wondering if my laptop charger would work or not, it says it's 19v/4.74A output on it.

mufc802 · 8 Jan 2011 at 20:04

Great, I found a 12v supply that is for my router, will that be ok? It's 1.5A.

mufc802 · 8 Jan 2011 at 20:09

fidget said:
Should be. Check it's an DC adaptor and not AC and that you get the polarity right.

It's AC, does that mean it wont work? It does seem to plug into the radios power input fine.

mufc802 · 8 Jan 2011 at 21:16

Steve2000 said:
Make sure the router supply is DC, if that's what the radio needs.

Also check the polarity. If it is centre negative and you put a centre positive adaptor into it you could damage it.

I don't really understand the bit about polarity.. it can only go in one way. How do I know if it's ok?

mufc802 · 8 Jan 2011 at 21:31

It's an AC adaptor, but not sure if that means AC to 12v DC or not.

mufc802 · 8 Jan 2011 at 21:36

Dfhaii said:
Is there a symbol with a flat line and a dashed line above it on the power supply anywhere?

What does it say on the back actually, or post a photo

http://cgi.ebay.co.uk/AC-Adaptor-AA-121A5D-OEM-12v-Power-Adaptor-New-/300487763085

mufc802 · 8 Jan 2011 at 22:46

Steve2000 said:
That outputs AC. If that's the plug you have and your radio needs a DC input, then that will probably fry it.

Can I ask how do you know if the output is AC or DC?

mufc802 · 8 Jan 2011 at 23:02

Steve2000 said:
If you look closely where it says Output 12v ~ 1.5A, the little ~ symbol means AC, if it was DC it would be a line with three short dashes underneath it.

Ah cheers, I have another router which does use a 12v DC input so I will use that.

What would actually happen if I tried to use an AC supply in a DC circuit and vice versa?

mufc802 · 9 Jan 2011 at 12:22

I finished putting the radio together today and tested using my Linksys 12v DC adaptor, and it worked fine.