power from cigarette lighter
Dave Martindale <[email protected]>
| Newsgroups | gmane.recreation.radio.hardware.icomr2 |
|---|---|
| Message-ID | <[email protected]> |
> From: Dan Jacobson <[email protected]> >Subject: success powering from car cigarette lighter wart > >Opening my Koka multi-voltage "800mA" automobile cigarette lighter >voltage converter ("wart"), I found a LM317T chip inside... the key to >success as mentioned on this list. At the 3V setting the wart powered >the radio perfectly, power save mode or not. Yes, because the LM317 maintains constant output voltage. >Hooking a multimeter between the battery and wart, one could measure >amperages as long as one doesn't select power save mode, which will >cause beeping of the radio. >I didn't dare hook the multimeter between the wart and radio this time >though. As explained before, you can use a suitable meter even in power save mode. You just need something with low enough series impedance, like a digital meter set to a 10A or 20A range, or a voltmeter measuring the voltage drop across a 0.1 ohm resistor. > One could see: with the radio off, very >little power was still used by the wart. In all other states, usage >was a little over 100 mA, speaker or light on or off, scanning or not. With the radio "off", there's still a DC-DC converter running and it draws a small amount of idle current. >Let's see. My 12V car battery is "24Ah"=240h*100mA=10 days of 24 hour >listening, max. Yes, although you'll kill your car battery if you do this repeatedly. Car batteries are designed for only a shallow depth of discharge before being recharged. Deep cycle batteries are built to withstand full discharges. Dave ------------------------ Yahoo! Groups Sponsor ---------------------~--> Get A Free Psychic Reading! Your Online Answer To Life's Important Questions. http://us.click.yahoo.com/Lj3uPC/Me7FAA/uetFAA/ELTolB/TM ---------------------------------------------------------------------~-> Post message: [email protected] Subscribe: [email protected] Unsubscribe: [email protected] List owner: [email protected] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/