One thing you have to check when running a laptop directly from a battery is which terminal is grounded in the laptop. If you connect the serial interface you connect the grounds together via the cable. or anything connecting them together could cause a short circuit even if the serial interface is not used.
I power my HP laptop directly from a linear power supply rather than use the noisy switching power supply. I measured the output voltage of the laptop supply and found it to be 12.4 volts. The lowest the linear supply would adjust to was 12.8v which is the voltage of a charged lead acid battery, it has been running on this supply for more than a year. The laptop had a negative ground even though the polarity of the dc connector had the outside + and the center - the reverse of the K2, so there was no problem connecting them together. My laptop and the K2 could run from the same battery. In my case the dc connector plugs are otherwise the same so you have to be sure they don't get plugged in wrong. Don't assume the voltage of the battery is the voltage of the power supply my laptop battery says 14.4v 2.5ah. '73 James AI4CQ _______________________________________________ Elecraft mailing list Post to: [email protected] http://mailman.qth.net/mailman/listinfo/elecraft You must subscribe to post. Subscriber Info (Addr. Change, Unsub etc): http://mailman.qth.net/subscribers.htm Elecraft page: http://www.elecraft.com
