Thanks for the info Dave. First, I have no sub RX so can´t comment on that.
When checking this I had 50 ohm terminator right at the SO239 antenna connector. The birdie indicates 2 bars on the S-meter with preamp ON and no indication with it OFF. This is subjective of course but with preamp ON those tuning pulses are quite loud, IMO clearly would be a problem. Of course with preamp OFF they do get quite weak however on a frequency like 28 MHz the preamp will be very much needed. Now when 10m opens up and we do get some "atmospheric" noise this tuning pulse deal might not be a problem. Here in town with antenna connected the tuning pulses cant be heard due to the high noise floor. However at my "real" radio station I have very very low noise floor. Maybe I am just to picky about things. Now as I did say before this birdie might be removable with the 3.03 FW, since 3.03 had some flaws I´m waiting for an update. Oh I see in your case it didn´t do anything the the 28005 thing. Yes same pitch change here when tuning across it, well lets call it a "internal created carrier" then. More exactly this 28005 thing is more like 28.0055 MHz in CW REV with normal pitch. Funny thing is, I put radio in config and in the "ACC REF" this carrier gets weaker. Guess some ACC REF oscillator, says it´s at 5.00. Maybe something can be done to it. I have to read the manual and see what it is. / Jim SM2EKM ----------------- David Gilbert wrote: > > With my K3 terminated in a dummy load and the preamp off, I can just > barely hear the decoder pulses. I checked it in both CW and SSB, and I > set both modes to 1 KHz bandwidth and adjusted the shift for the same > center frequency of 600 Hz. With the preamp on they are more > noticeable, making the S-meter briefly tick up to about S2 if I tune > quickly. When I stop tuning, of course, the pulses disappear so I'm not > sure they would ever actually hinder me from making a QSO. > > Here's an interesting quirk ... possibly just my imagination but I don't > think so. I have the subreceiver installed, and if I engage it so that > I can simultaneously hear the main receiver in my left ear and the > subreceiver in my right ear, tuning the subreceiver across 28005 creates > louder decoder pulses in the main receiver than it does in the > subreceiver. Then again, I have never found as many birdies in the > subreceiver as I have found in the main receiver, and those I've found > in the subreceiver are at least ten db weaker than their main receiver > counterparts. > > I do not hear any birdie at that frequency, though. If I listen very, > very hard with the preamp on, I can hear a tone just under the > background noise, but I have to tune the VFO to hear the changing pitch > in order to detect it. Without the preamp on, it is impossible to hear > it at all. It isn't a birdie, though ... the pitch changes smoothly and > slowly as I tune across it. I have found (and removed via SIG RMV) a > few other birdies on 10m, on my rig 28005 isn't one of them. > > I do believe that tuning artifacts vary quite a bit from K3 to K3, > though, so you may be experiencing a much greater problem than I am. If > so, you may want to consider making an audio recording of it so that the > rest of us can hear it. > > 73, > Dave AB7E > > > > > Jan Erik Holm wrote: >> When 10m opens up this will be a serious problem. >> >> On 28005 KHz a quite strong birdie carrier, on >> each side of this carrier there are "tuning pulses >> generated from the encoder in the segment 28000 to >> 28010 KHz. All this gets stronger with Preamp ON. >> >> Is it only my K3? Or is this on all of them? >> >> Any solution? >> >> This internal carrier might be removed with the >> new FW but any solution for this tuning puls >> problem. >> >> 73 Jim SM2EKM >> ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
