Re: [Elecraft] KX3 external battery (Maxtron) VERY NOISY
Yup. It is not a 12 or 13.8V battery, but rather a low voltage source that has a switching circuit ( aka noise) that generates the higher voltages, These are designed to do as advertised and charge phones and tablets at relatively low current. If you want battery operation, an SLA or LIFE battery is your best choice. -- View this message in context: http://elecraft.365791.n2.nabble.com/KX3-external-battery-Maxtron-VERY-NOISY-tp7599790p7599799.html Sent from the Elecraft mailing list archive at 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] KX3 external battery (Maxtron) VERY NOISY
On Fri,3/6/2015 12:43 AM, Dominic Baines wrote: Yeah it is an oxy moron sometimes... operate off grid using a battery and you get noise (this will be the internal LiION battery recharging/regulation circuitry causing it). Probably so. Have you tried adding ferrite to the DC leads (and weirdly to the headset leads, I need to if using ext battery sometimes). You could make up a simple choke and plug your rig power lead into that, doesn't need to be in a box or anything... leads from battery then 12 turns of the power leads or so in opposite directions in parallel on the ferrite (try FT240-61) to a set of connections to the rig. #61 is a VERY poor choice for suppressing noise at HF. #31 and #43 are the weapons of choice for the HF bands. Or a string of those little 5mm ID clip on ferrites (ebay) on the Elecraft lead. Strings of beads or clip-ons are NOT effective at HF. Study k9yc.com/RFI-Ham.pdf 73, Jim K9YC __ 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
Re: [Elecraft] KX3 external battery (Maxtron) VERY NOISY
Yeah it is an oxy moron sometimes... operate off grid using a battery and you get noise (this will be the internal LiION battery recharging/regulation circuitry causing it). Have you tried adding ferrite to the DC leads (and weirdly to the headset leads, I need to if using ext battery sometimes). You could make up a simple choke and plug your rig power lead into that, doesn't need to be in a box or anything... leads from battery then 12 turns of the power leads or so in opposite directions in parallel on the ferrite (try FT240-61) to a set of connections to the rig. Or a string of those little 5mm ID clip on ferrites (ebay) on the Elecraft lead. 72 Dom M1KTA Owner of #1082 #2334 On 06/03/15 04:53, Robert Sands wrote: A reflector poster mentioned the Maxtron MX 160A for use with the KX3. I got one off Amazon and tried it. My noise level jumped from S4 to S9.Not sure how to eliminate it.Nice otherwise.Transmit plug it in. Receive, pull it out. Robert E. Sands K7VO __ 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
