Re: [Elecraft] K3 spurs
If you have an older K3 there was a problem with them generating a spur. I had the problem when a friend reported hearing me on a 2nd freq.I'm guessing nobody still has an older K3 though with this problem. We have determined that a small number of K3/100s and KPA3s left the factory earlier this year (2009) with capacitor C3 installed by mistake on early Revision C KPA3 PC boards. This part location should be empty on Rev. C KPA3s. Installation of C3 causes the PA bias supply to oscillate on some KPA3s at approximately 15-20 kHz, resulting in spurious TX sidebands at that spacing from the carrier. Info is on the Mods & Notes page almost at the bottom. http://www.elecraft.com/K3/k3_app_notes.htm BillK3WJV On Tuesday, May 15, 2018, 9:30:41 AM EDT, Roger D Johnson wrote: I was watching 6m yesterday and noticed several spurs. They were spaced 39kHz apart. Amplitude dropped but didn't disappear when switched to dummy load. I have the K3 with new synthesizer boards. Just wondering if anyone else seeing something similar. IOW is it something in the K3 or external? 73, Roger __ 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 k3...@yahoo.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] K3 spurs
I've seen a K3 generate spurs when the power supply was overloaded, and went into current limit. 73, Scott K9MA On 5/15/2018 15:38, Clay Autery wrote: I don't know where your antenna is located, how your feedline runs, or where your dummy load is located, but You have some kind of switch mode power supply or similar device that is coupling with your antenna and/or feedline. That the signal dissipates some when on the dummy load is a clue to where the source might be... I'd be almost positive it is external to the K3... Are you powering the K3 with a SM power supply? 73, Clay, KY5G On 05/15/18 09:22, Roger D Johnson wrote: I was watching 6m yesterday and noticed several spurs. They were spaced 39kHz apart. Amplitude dropped but didn't disappear when switched to dummy load. I have the K3 with new synthesizer boards. Just wondering if anyone else seeing something similar. IOW is it something in the K3 or external? 73, Roger __ 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 k...@montac.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 k...@sdellington.us -- Scott K9MA k...@sdellington.us __ 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] K3 spurs
I don't know where your antenna is located, how your feedline runs, or where your dummy load is located, but You have some kind of switch mode power supply or similar device that is coupling with your antenna and/or feedline. That the signal dissipates some when on the dummy load is a clue to where the source might be... I'd be almost positive it is external to the K3... Are you powering the K3 with a SM power supply? 73, Clay, KY5G On 05/15/18 09:22, Roger D Johnson wrote: I was watching 6m yesterday and noticed several spurs. They were spaced 39kHz apart. Amplitude dropped but didn't disappear when switched to dummy load. I have the K3 with new synthesizer boards. Just wondering if anyone else seeing something similar. IOW is it something in the K3 or external? 73, Roger __ 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 k...@montac.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
[Elecraft] K3 spurs
I was watching 6m yesterday and noticed several spurs. They were spaced 39kHz apart. Amplitude dropped but didn't disappear when switched to dummy load. I have the K3 with new synthesizer boards. Just wondering if anyone else seeing something similar. IOW is it something in the K3 or external? 73, Roger __ 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
