I'm not sure where the voltage displayed on the K3 is sampled, but I have found it to be consistently about a volt lower than the voltage present at the Power Pole connector on the back of the radio, especially when in transmit mode. I have found this to be the case on both the K3 I use for portable ops and my K3S in my home "shack".
Just FYI. 73, Ken, KJ9B -----Original Message----- From: elecraft-boun...@mailman.qth.net <elecraft-boun...@mailman.qth.net> On Behalf Of Corky Sent: Wednesday, September 4, 2024 2:27 PM To: W3FPR <w3fpr...@gmail.com>; RIchard Williams via Elecraft <elecraft@mailman.qth.net> Subject: Re: [Elecraft] K3 Power Issues Don, I am not sure exactly what "problems go away" means here. Moving it to the separate power supply, cleaning the power terminal contacts on the K3, and upgrading the power cable eliminated the brownout problem with the K3. Increasing the voltage will certainly give me more headroom to play with. As for measuring the power at the K3, the only thing I have to go on is the reading from the K3 itself. Everything else I could come up with as a means to measure the voltage at the terminals during TX involved adding something else into the power chain, thereby increasing the resistance/voltage drop in the power cable. If anyone has a solution for getting a voltage measurement at the power terminals without adding in a jumper I would be appreciative. Otherwise I guess I can see what the K3 says for voltage drop with and without the jumper to see if there is a change. Thanks and 73, -Corky, AF4PM On Sun, Sep 1, 2024, at 4:10 PM, W3FPR wrote: > Corky, > > If you can adjust the power supply output, set it to 14.3 volts and > see if the problems go away. > Measure at the K3, not at the power supply. > Eliminate your power distribution system and connect the K3/P3 direct > to the power supply. > > Let us know if that helps. > > 73, > Don W3FPR > > On 9/1/2024 5:55 PM, Corky wrote: > > I was having trouble with my P3 going into brownout mode when transmitting 50 Watt digital. This used to be fine, but seems to have been getting worse over the past several months. When I monitored the power on the front panel of the K3 I found it was dropping about 1.5 V when transmitting digital signals. This would occasionally drop below 12 V and cause the P3 to go to brownout and shut down. > > > > > ______________________________________________________________ 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 ken.k...@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 arch...@mail-archive.com
