The specs are in the manual, which is online as a PDF. http://www.elecraft.com/K2_Manual_Download_Page.htm
Supply Voltage and Current: 13.8 V nominal (11 V min, 15 V max) Recommended supply: 13.8VDC @ 25A, continuous duty for K3S/100; 13.8VDC @ 6A for K3S/10. Both on page 8. wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Apr 17, 2018, at 11:36 AM, Buck <radiok...@gmail.com> wrote: > > What is the minimum recommended voltage for the K3S? Using the stock > Elecraft 5' cable, I drop from 13.3 to 12.7 volts on key down. > > Buck, k4ia > Honor Roll > 8BDXCC > EasyWayHamBooks.com > > On 4/16/2018 4:51 PM, Joe Subich, W4TV wrote: >> On 2018-04-16 4:26 PM, hawley, charles j jr wrote: >>> So 4 sets of power pole connectors plus 2 fuses. >> Even if the power pole connectors are assembled perfectly and >> mated with optimum tension, the resistance in just the four >> (15 A) power pole connectors in the negative lead is equivalent >> to nearly 40 feet of #12 copper wire! >>> The voltage at the rig, K3, now drops a volt when putting out 100 >>> Watts. >> With the equivalent of 50 feet of power cable (4 connectors plus a >> 10 foot physical cable), I would not be surprised. Assuming 20A >> in transmit (on 15A power poles!), a 1V drop represents 0.05 Ohms >> of total circuit losses .... that's pretty good for 10 feet (x2) >> of cable plus eight connectors (4 in the + lead, 4 in the - lead) >> and the switching device (probably a Schotkey diode). However, >> the 0.05 Ohms in the negative lead is probably ten times higher >> than in a braided bonding connection directly from the K3 chassis >> to the power supply chassis. >> I'm surprised that only 75% went through the ground path - that >> indicates the ground path has 1/3 as much resistance as the "right" >> (V- lead) path. >> 73, >> ... Joe, W4TV >> On 2018-04-16 4:26 PM, hawley, charles j jr wrote: >>> About 75% went thru the ground path. The 10 ga to the rig went from Astron >>> to a battery switching device in case of power outage, to rig runner and to >>> rig. So 4 sets of power pole connectors plus 2 fuses. I’m thinking of >>> changing some of that too. The voltage at the rig, K3, now drops a volt >>> when putting out 100 Watts. >>> >>> Chuck Jack >>> KE9UW >>> >>> Sent from my iPhone, cjack >>> >>>> On Apr 16, 2018, at 3:14 PM, Wes Stewart <wes_n...@triconet.org> wrote: >>>> >>>> I would hope that "much of the current..." wasn't really much. The direct >>>> conductor from the negative terminal of the power supply to the radio >>>> should carry the majority of the supply current, >>>> >>>> Wes N7WS >>>> >>>>> On 4/15/2018 7:38 PM, hawley, charles j jr wrote: >>>>> This thread prompted me to check out my Astron vs35m. It had a small >>>>> black wire from -V connected to the bottom of the chassis. Perhaps it >>>>> could be called a case or cabinet...more importantly, it’s what the green >>>>> wire from the line cord is connected to. I disconnected the black wire. >>>>> When it was connected, much of the current that would have passed thru >>>>> the negative power wire from the power supply to the rig was shunted thru >>>>> the green power cord wire, the ground buss bar, and other ground >>>>> connections. >>>>> >>>>> Chuck Jack >>>>> KE9UW >>>>> >>>> >>>> ______________________________________________________________ >>>> 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 >>>> Message delivered to c-haw...@illinois.edu >>> ______________________________________________________________ >>> 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 >>> Message delivered to li...@subich.com >>> >> ______________________________________________________________ >> 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 >> Message delivered to radiok...@gmail.com > ______________________________________________________________ > 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 > Message delivered to wun...@wunderwood.org ______________________________________________________________ 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 Message delivered to arch...@mail-archive.com
