Dave - About 5 minutes after I hit [SEND] on that last e-mail, I remembered that I'm not using the supplied DC cable, but instead have a rather long DC cable running to the K3; I'm sure that's where the loss is coming from. I'll look into shortening it.
I also soldered the PP connections. I've left my DM-330MV set to the default 13.8 v, but raising it is certainly easily doable. Thanks again & 73, Steve NN4X On Sun, Apr 5, 2009 at 12:08 AM, David Gilbert <[email protected]>wrote: > > Glad that helped, Steve. > > You might want to continue your troubleshooting, though. I use exactly the > same Alinco DM-330MV power supply with the same stock Power Pole connectors > that came with the K3, and while I have considered shortening the power > cable that Elecraft provides I have not yet done so. I normally have my > DM-330MV set for 14.5 volts per the earlier discussions here on the > reflector about SSB linearity, but I temporarily adjusted the voltage back > down to 13.6 volts in receive to match your conditions. With the K3 set to > 95 watts, I show 13.0 volts in transmit. At 45 watts, I'm holding 13.3 > volts. > > I'm not sure what the difference might be, but we're getting significantly > different results from the same power supply. For what it might be worth, I > carefully soldered the connections between the cable and the Power Pole > connectors when I assembled it. > > 73, > Dave AB7E > > > > > S Sacco wrote: > > Hi Dave - > > OK, sorry for the misunderstanding; I thought you were talking about the > K3's internal battery. > > Now that we have that out of the way: > > 1) "BAT MIN" is set to 11.0 v > > 2) When I measured the voltage using the K3's internal metering: > a) It was 13.6 v at receive > b) It was 10.8 v while transmitting 95 watts output **** Clearly, 10.8 > < "BAT MIN" **** > > 3) I measured disconnected and reconnected the Anderson Power Pole > connector at the back of the K3, and the voltage increased to 10.9. > > 4) I have the power from the power supply (an Alinco DM-330MV) running to a > set of fuses before continuing on to the K3. It's one of those gold-plated > dressy looking deals that car audio folks use to bling-out their > installation (I got them cheap at Skycraft Surplus here in Orlando about 10 > years ago). > a) I removed both fuses (one for +, one for - ) and treated both the > fuse and the holder with DeoxIT. > b) At the same time, I treated the PowerPole with DeoxIT. > c) I also noted the the - lug on the back of the Alinco was slightly > loose, so I tightened it. > d) My apologies for not doing one thing at a time, and then measuring > the result; that would have been the proper procedure. > e) Upon the above treatment and actions: > i) The voltage rose to 13.7 v at receive > ii) The voltage rose to 11.4 v while transmitting 95 watts > iii) To add another datapoint, I reduced the power to 45 watts > (typical power when driving my amp) and the voltage was 12.0 v. > > Conclusion: Voltage drop due to I squared R losses. > > I didn't measure the voltage on both side of the fuses before the DeoxIT > treatment, which was another mistake in my diagnostic approach. I did so > after the treatment, and noted a voltage drop of only .1 volt (from 12.9 to > 12.8) across the fuses while under load. > > Thanks for the tip Dave; it was much appreciated! > > I've Cced the reflector, and hope this serves as a good example for > everyone to mind their connections. > > 73, > Steve > NN4X > > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
