A 1.5 A regulator isn’t going to handle the 12 to 20 A drain of an HF Radio.
Sent from my iPhone ...nr4c. bill > On Jul 18, 2018, at 11:22 PM, Bob McGraw K4TAX <[email protected]> wrote: > > Why not use a 7812 three terminal regulator? It will accept up to 30 V on > the input, deliver 12 V on the output at 1.5 amps. These cost about $1.50 or > less. If one needs more current then add a 2N3055H as a pass transistor > for up to 5 amps of current. > > Another choice is a regular AC 120V power supply, remove the transformer and > bridge rectifier, feed the 24 volts to the unregulated input, where the > bridge rectifier was connected and you have 12V DC regulated. These should > be available for $10 to $20 new. just don't buy a switching supply. > > 73 > > Bob, K4TAX > > >> On 7/18/2018 9:50 PM, Dennis Haarsager wrote: >> I just bought a 24V 3.5A battery to power my CPAP machine when AC isn’t >> available. Would be nice if I could use it to power my KX2 or KX3. 24v-12V >> down converters are cheap, but the only 24V-13.8V one I’ve found so far is >> an order of magnitude more. Does anyone think the extra cost is worth it in >> terms of extra tx performance? >> >> 73, >> Dennis, N7DH/1, MM/N7DH >> >> Sent from my iPhone >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [email protected] > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
