Bob, The power strip is gone for the K3's. Now direct connections from the PS to each K3. The power strip is good for replacing the walwarts. N2TK, Tony
-----Original Message----- From: elecraft-boun...@mailman.qth.net <elecraft-boun...@mailman.qth.net> On Behalf Of Bob McGraw Sent: Sunday, December 22, 2019 12:45 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 - Power cable voltage drop Rid your station of the DC power strip. It will cause problems. More connections in the path will be more DC voltage drip. The radios should be connected direct to the power supply. As to the Astron SS-30M, I have 3 of those. They are great. I did find the provided DC connections where the wires are inserted into the blocks and secured with a screw from the side would not accommodate the 4 needs for DC at my station. Therefore, I took two pieces of 2" x 10-32 brass machine screw, cut off the head, filed a small flat spot on one side at the end to make it slightly D shaped. Inserted that end into the DC connector and tightened the set screw against the flat spot. Then added as needed the brass nuts, flat washers and lock washers, secured finally by another brass nut. This in effect gives me very adequate terminal length to attach as many DC power leads with suitable ring terminals as needed. DC resistance has therefore been minimized. The 10 ga wire is a good addition for radio power needs. I also added a dedicated ground between the ground screw on the back of the radio to the ground screw on the power supply. 73 Bob, K4TAX 12/22/2019 10:47 AM, N2TK via Elecraft wrote: > I have been using an Astron SS-30M power supply for several years to > feed two K3's. > I use 12ga wire from the power supply to an MFJ-4012 power strip. From > the power strip I use 12ga wire to each K3. Total length from power > supply to a > K3 was 8'. Each K3 is set for 100W on 30M into a dummy load. The K3's > were tested one at a time. The power supply voltage went from 14.38 to > 14.30 at 100W. > Both K3's read the same on the K3's internal voltmeter - 14.1V in > receive and 12.7V at 100W setting on the K3's. The P3 read 107W out. > Changed the cable to 10ga wire direct from the power supply to each K3. > Length of each is 7'. Same test. Power supply voltage was still 14.39/14.30. > Voltage on each K3 was now 14.2v. Key down 13.6V. So, 0.6V drop in 7' > of 10ga wire. > P3 output was now 114W. > I never transmit with both K3's at the same time. > Just a data point. > 73 and Merry Christmas > N2TK, Tony > > > ______________________________________________________________ > 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 > rmcg...@blomand.net > ______________________________________________________________ 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 tony....@verizon.net ______________________________________________________________ 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
