Lepai LP-2020A+ Amp with lighter plug?

[Mikers]

Hi

Can I use one of these to power my Lepai? http://www.tessco.com/products/displ...16&eventPage=1

My holiday trailer has a lighter receptable that runs off the battery. When I'm camping with only the trailer batteries it would be nice to just plug into that and not have to have a boom box with batteries.

Since the Lepai runs off 12v, I don't see a problem, is there?

[NickS]

http://www.parts-express.com/pe/show...number=265-562

These are less expensive if you want to put you own wires on it. Just make sure to get the polarity correct. You might just put a smaller amperage fuse in it (it comes with a 5 amp).

[Mikers]

how can you determine the polarity?

I'm thinking I just remove the plug that came with the amp and replace it with the lighter plug, keeping the amp end of the cable intact.

[Chris Roemer]

how can you determine the polarity?

I'm thinking I just remove the plug that came with the amp and replace it with the lighter plug, keeping the amp end of the cable intact.

You use a DC voltmeter (DMM) to measure the 12v polarity at the end of the plug off the supplied (Vonage?) wall wart, then make sure it's the same off the end of the cord on your lighter plug.

If you hook it up backward, there's NO internal protection to keep your Lepai from popping and smoking (and stinking) inside. I know, 'cause that's exactly what I did. Replaced a couple electrolytic caps inside, but still no sound (although the blue volume knob LED works again).

You can get a cheap DMM from Harbor Freight for $3-$5, sometimes even for free (with a coupon).

Chris

[Dirk]

I'm 99.9% certain that pin is positive, barrel is ground. That style connection ensures that ground touches before power is applied.

Still, verify everything, lest you end up ordering another Lepai.

[JimHRB]

I seem to recall there was a problem with powering the Lepai 2020 with voltages over 12V. If you intend to use this in a car or boat with the engine running, the voltage will be above 12V (typically 13.5 or so) due to the alternator charging it.

[Chris Roemer]

I'm 99.9% certain that pin is positive, barrel is ground. That style connection ensures that ground touches before power is applied.

Still, verify everything, lest you end up ordering another Lepai.

I've got (cheap) DMMs all over the house.

I assumed that the end pin was + and the lighter plug sides were -, and that's how I alligatored it to my 12v gel cell. Lots of smoke. Turned a perfectly working 2020 into a box of spare parts.

All I had to do was check first.