Hi... I have a KX3 and normally run it on batteries. I also have a Flex-6500 that runs on a big RS-50.
Last night during the QRP Fox Hunt (only 1 pelt) I decided to shutdown the Flex and give the KX3 a shot. I powered up the Flex on its internal batteries and, while I had the headphones on, plugged the RS-50 into it. I was surprised with what I heard. Not only a low freq hum (60 or 120 Hz, can't tell) but also a hash sound. The affect was fairly dramatic. I never noticed anything on the Flex because I never ran that on batteries. Today I swapped the KX3 between an old RS-12 linear I had laying around, a 12 V 15 Ah LiFePO4 battery pack and the internal batteries. Going from internal (9.9V) to LiFePO4 (13.0V) I could hear no difference and see no difference on the S-meter. I tried with the antenna connected and disconnected. Going from internal to the RS-12 (13.5 V) i could hear an increase in noise level, about +S1, almost like turning up the RF gain a tad. When the antenna was removed I heard no difference between internal battery and RS-12. The additional noise wasn't objectionable - just sounded like the noise floor jumped up a bit. No hum, no hash (or hiss). I'm not sure what to make of this. It is apparent my RS-50 is in need of some attention. I've had hit-and-miss experiences with Astron over the years and now seeking an alternative. I just want something to work and work well. I'm not even sure the RS-12 is up to spec with the small increase in noise. My expectation is no change in noise going between battery and power supply. Is this unrealistic? eham's reviews are kind of not very helpful. There's plenty of good and plenty of bad said about most makes and models. I'm thinking maybe I want to run 100% battery for both the Flex and KX3 and just recharge when not in use but I'm not sure how realistic that is. I do know I don't want to just settle for the additional noise. Switchers don't seem to be an option. While it might sound quiet at the moment I can always see/hear that noise snake crawling across the panoramic display right towards my current QSO. Has anyone done some A/B comparisons while listening? I'm curious what you may have experienced. Thanks, Kev K4VD (VD = Vacation Day) ______________________________________________________________ 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 Message delivered to [email protected]
