Mike Coslo wrote:
N2EY wrote:

I think they are using a laptop, because I don't know any desktops
that run on 12 volts DC (though there are probably some). It sounds to
me like what they did was to use a laptop with a charging cord meant
to go into an auto accessory power socket. That way, the primary power
comes from the 12 volt power system they need for the rig, and the
laptop's internal battery is used for backup in case there is some
sort of power interruption.

FD lasts more than 24 hours, and I don't know any laptops whose
batteries will run that long. Using external power means no
interruptions.

An awful lot of laptops run on 18 Volts DC. My IBM's Dells, snd most
recently, a Toshiba. (actually it is 19 Volts) If you aren't going to run
them off 120 volts and their own power supply, you'll need to run a DC to
DC p.s.

- 73 de Mike KB3EIA -

I so do dislike quoting myself but, "The logging PC will have it's own
homebrew DC-DC boost converter."
The laptop PC's AC power supply produces 16VDC @ 4A. The DC-DC boost
converter produces regulated 16VDC @ 4.5A. The boost converter for the rig
similarly produces 14VDC @ 25A. Both units are dead quiet in terms of EMI,
and aren't upset in the presence of RF.
Bryan WA7PRC