Be sure to use a DVM external to the K3 to measure the voltage at the K3. The input protection diode in the K3 will cause some drop (1/4 to 1/2 volt perhaps). What this means is that the K3 meter will always show less voltage than is really present at the transceiver supply input.
73! Jack, W6FB > On Feb 26, 2019, at 9:37 AM, mjpilgrim <mpilg...@bellsouth.net> wrote: > > Well, i have received many helpful replies both publicly here and in private > emails. Thanks to all for those ideas brought forward. > > What I've gleaned to be most useful from your responses has been the > suggestions to investigate the power cord with power poles connecting the K3 > to my switching power supply. Per those inputs I've fabricated a shorter > (5') cable and insured that I used the crimp terminals rated at 30 AMPS. > The initial result has been a reduction of about 30% of my measured voltage > drop (now 13.6 Volts in standby to 12.5V when key down 100W CW........ > previously the drop was to 12.0)............... Some background info. is > that the original observation of a voltage drop occurred as the K3 was > connected to my minimal-sized Solar Power supply. After extensive > investigation, additional hardening in the wiring, and replacement of a > suspect imported power distribution strip, I was convinced there was no > voltage drop evidenced there. The battery voltage measured at the input to > the referenced DC power distribution strip did not waver under key down > tests with the attached K3............. There remained however, the > above-mentioned voltage drop displayed in the K3 metering. > > i plan to rebuild the afore-mentioned 5' power cable, this time soldering > the power pole lugs rather than trusting crimped connections. My suspicion > that the power cable is suspect, so i plan to address those curiosities > before moving on to other possible cause. > > Thanks again for your continued ideas and suggestions. > Regards, > Mike, K5MP > > > > -- > Sent from: http://elecraft.365791.n2.nabble.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 ______________________________________________________________ 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
