I've done that, Buck, still noisy. Many Thanks, 73, John On 13/12/2012 21:57, Buck - k4ia wrote: > I have found that I must be sure to screw in (not just plug in) the > serial connector on the back of the K3. If I don't, I will hear a > pulsed rushing noise from the USB. > > > Buck > k4ia > > On 12/13/2012 12:53 PM, Matthew Zilmer wrote: >> USB uses differential signaling. Your problem may not be conductive >> noise, but instead it could be radiated directly from the adapter, >> where the ferrite won't help. >> >> KeySpan makes a USB - serial adapter that is pretty much noise-free. >> Its model is HS19, I think. >> >> Matt Zilmer >> Consultant - Product Management Dept. >> Magellan Navigation / MiTAC Digital Corp. >> Tel: (909) 394-6052 >> Cell: (909) 730-6552 >> In status quo voluntas non sufficit >> >> >> -----Original Message----- >> From: elecraft-boun...@mailman.qth.net >> [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of john petters >> Sent: Thursday, December 13, 2012 9:25 AM >> To: elecraft@mailman.qth.net >> Subject: [Elecraft] KUSB Noise Query - K3 >> >> Hi Folks, >> I posted a query about K3 Serial ports a few months back - we could >> not get the K3 to work properly with the RS232 connection. It turned >> out to be a fault with the sound card, which took out the serial >> connections. >> When I first built the K3, I bought a cheap Prolific USB converter, >> which radiates awful noise over the spectrum. I decided to bite the >> bullet and buy the proper lead, which arrived today. >> >> Using my Toshiba laptop, on battery power, I get a couple of s points >> of noise on 10M with the KUSB connected and HRD fired up. This is >> using my >> 2 element DJ4VM quad, which is fed with 300 ohm twin into the shack, >> i.e. near the laptop. >> >> On LF, I can hear the pulsing information, in sympathy with the >> flashing LEDs on the KUSB on 160M at quite a high level. I can even >> detect this when fed into a Marconi dummy load. The K3 and the tuning >> units are bonder to an RF earth - a copper stake about 8 feet away >> from the K3. >> >> I have tried choking the USB lead at the laptop end, which does reduce >> the noise to a degree. >> >> The question I have is - am I being unrealistic in expecting zero >> noise to be radiated from these adaptors? >> Does anyone else have this problem - or has anyone looked for it? >> >> It is not very noticeable on CW or SSB. To hear it best, listen in the >> AM mode with the AGC off. On SSB it sounds like band noise. >> >> Is this a problem JUST with USB adaptors or can I expect silence when >> connecting a computer via RS232 to RS232. >> >> If not we are sacrificing a low noise floor for the convenience of >> computer control. >> >> Any views appreciated, >> >> 73 >> >> >> >> >> -- >> John Petters >> www.traditional-jazz.com >> Amateur Radio Station G3YPZ >> ______________________________________________________________ >> 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 > > ______________________________________________________________ > 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 >
-- John Petters www.traditional-jazz.com Amateur Radio Station G3YPZ ______________________________________________________________ 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
