Re: [Elecraft] KX3 - Does It need Preamp for 6M?
On 6/20/2013 10:25 AM, Edward R Cole wrote: I would dispute the advantage of mast mounting a preamp on 6m. It all depends on how much loss is in your run of coax, and how quiet your location is. The run to my SteppIR is 350 ft of 7/8-in hard line, just under 1 dB at 50 MHz, and my QTH is not very quiet, so I'm happy with my ARR GasFET preamp at the K3 patch point. The decision to mast-mount or not is pretty simple. If you hear the band noise increase by at least 7 dB when you connect the antenna, leave the preamp in the shack. If the noise rises by only a few dB, compute the loss in your line (see mfr data for the coax you're using). If the noise increases by only 3dB with the connected (and no preamp), you'll see an increase in your ability to hear weak signals of roughly one third of the line loss. If the noise doesn't increase at all, you'll see in improvement equal to ALL of the line loss. How much is a dB worth? It all depends how close to the noise level the signal is that you're trying to copy. If it's VERY close to the noise, a dB or two can be the difference between making and missing the QSO. 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
Re: [Elecraft] KX3 - Does It need Preamp for 6M?
Jim Mine seems to be as good as any radio that I have owned except for the K3 without the external one. I have been making many 6m QRP contacts SSB with my KX3 to date 47 total in the last several weeks, using a small yagi. If I were going to work weak signal usually not much done QRP a mast mounted preamp would be in order. 73, Fred/N0AZZ K3 Ser #'s 6730/5299--KX3 # 2573--K2/100 # 6470-KAT100 P3/SVGA--KPA500--KAT500--W2 -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Jim Brown Sent: Wednesday, June 19, 2013 9:43 PM To: Reflector Elecraft Subject: [Elecraft] KX3 - Does It need Preamp for 6M? We may use a KX3 in a very quiet mountaintop QTH on FD. Does it need a preamp for 6M? Notice that I said a VERY QUIET location. 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 - No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.2904 / Virus Database: 3199/6425 - Release Date: 06/19/13 __ 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
Re: [Elecraft] KX3 - Does It need Preamp for 6M?
Typical MDS on 6 meters with the 30 dB preamp setting is around -140 dBm. This should suffice for all but the most stringent low-noise applications. 73, Wayne N6KR On Jun 19, 2013, at 7:43 PM, Jim Brown wrote: > We may use a KX3 in a very quiet mountaintop QTH on FD. Does it need a preamp > for 6M? Notice that I said a VERY QUIET location. > > 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 __ 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