Quick ? for all you smart ppl
 

Hey there,

I'm going on a little road trip in a few days and.. well here's the deal..

Going in my friend's minivan (no protegé unfortunately :() and she recently had her in-dash cd player stolen, so no means of listening music.. so i got to thinking.. I have a portable Discman CD Player and some decent speakers that'll plug into the headphone jack of it. It wont be great but i figure it's better than nothing.. The only iffy part is Power.

Both the CD Player and Speakers run AC Adapters, Im not an expert on this stuff so forgive me.. here are what the labels say:

CD Player: Input: AC 120V 60Hz 8W
Output: DC 4.5V 600mA

Speakers: Input: 120 VAC, 60Hz, 14W
Output: 12VDC
Current: 800 mA Max

I figure I can get the power from the Cigarette Lighter with an inverter .. looking at this one: http://www.radioshack.ca/estore/Prod...log=RadioShack which gives 50 watts.. I'll need to run both the CD Player and Speakers simultaneously (obviously :)) so ill also just pick up a splitter thing that turns one socket into two.

Soo... I'm just wondering if this'll work? :) And will the load be alright for continued use on the van's battery? Sorry for the lengthly post, if you guys could help I'd be very happy :)

should work just fine... according to your numbers the absolute max. pulled by the two AC/DC transformers is 22W.

That would work out to about 1.5A @ 13.6V plus the loss of the inverter... figure at worst 50% efficeint... that is 3A. And that is a very gross maximum... it should never be that high. Considering that most lighter circuits have at least a 10A (usually a 15A) fuse on them I would say you are in the clear.

Heck, I run my soldering iron off an inverter!

Well these are self powered speakers running off of a AC/DC transformer power supply that is only rated for 12VDC @ 800mA max... so that would only be 9.6W...

another setup would be fine up to ~50W input power, considering that amplifiers are not 100% efficient. Ranging from a good class A amp (50% efficient when properly designed, very good fidelity) to bass thumping amps (class D, E, and what ever else they can get to produce a good low frequency note, which run at better efficiencies).

does the system have amplifiers? if so, then you can output from the discman's line out to the amps RCAs. Rad Shack has RCA to 1/8" adapters.