Bill, I would suggest an Astron 20 amp supply (or even the 35 amp linear). Yes, it is overkill for the 12 watt KX3, but that is no problem, the current will not exceed what the connected device (the KX3) needs even though the supply is capable of much more current. When you also have the KXPA3, you will need that extra current. You also have other 12 volt powered devices around the shack, so the extra current rating will help with powering those devices.
For those who want to homebrew for the basic KX3, I suggest you look at the article in QST from November 1993 page 27 for a 5 amp regulated 13.8 volt 5 amp power supply with crowbar overvoltage protection. We are hams, so think "build your own" It is a good philisophy/ 73, Don W3FPR On 9/18/2012 4:53 PM, Bill Tubbs wrote: > After sending my note about using the little MFJ power supply at 2.89 amps, I > realized that it works fine on my FT-817D at 5 watts but would obviously be > taxed at the full 12 watts of the KX3. So fuggetabowdit. > > Now I'M looking for a sufficient supply for the KX3 ;-) > > Bill > WK6A > > Sent from my iPhone > > On Sep 18, 2012, at 4:44 AM, Johnny <vr2...@yahoo.com.hk> wrote: > >> Yes , correct , laptop supplies are often RF noisy. >> >> Sent from my iPhone 4 >> >> "Fred Townsend" <ftowns...@sbcglobal.net> 於 2012年9月18日 下午2:04 寫道： >> >>> Jeff, caution. Laptop power external supplies are designed to be followed >>> by precision internal regulators that handle the logic voltages and charging >>> the battery. The external supplies are not well regulated and can be quite >>> noisy. They may not be the best supplies for ham rigs. >>> 73 >>> Fred, AE6QL >>> >>> -----Original Message----- >>> From: elecraft-boun...@mailman.qth.net >>> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Jeff Herr >>> Sent: Monday, September 17, 2012 6:40 PM >>> To: 'Elecraft Reflector' >>> Subject: [Elecraft] laptop power supply to power KX3 >>> >>> While at work I went through our stock of power supplies for the various >>> makes of laptops we use. >>> I found that Toshiba supplies are specified 15v and ranged in current >>> capability from 2.5 amps and up. >>> >>> Dell, Lenovo, HP, Acer, Asus all use 19v supplies. >>> >>> Those Toshiba supplies are very small. >>> >>> WW6L >>> >>> >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:Elecraft@mailman.qth.net >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
