Matt & Brian, thanks for the suggestions. This KUSB is the latest type, I believe with the FTDI chip set.. The old one I had was a Prolific chip set - but not a KUSB. I'll look up the HS19. 73 John
On 13/12/2012 18:10, Brian Moran wrote: > You may try a different K-USB. I have a K-USB that radiated terrible > noise on 160m. A different one, quiet. > -Brian N9ADG > > > ------------------------------------------------------------------------ > *From:* Matthew Zilmer <mzil...@magellangps.com> > *To:* john petters <tjp...@traditional-jazz.com>; > "elecraft@mailman.qth.net" <elecraft@mailman.qth.net> > *Sent:* Thursday, December 13, 2012 9:53 AM > *Subject:* Re: [Elecraft] KUSB Noise Query - K3 > > 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> > [mailto: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 <mailto: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 <http://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 <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 <mailto:Elecraft@mailman.qth.net> > > This list hosted by: http://www.qsl.net <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
