Hi Matt, The "zipper" or "motorboat noise" occurs when tuning around 4.9-5.5 MHz or 4900-5500 KHz. It is most noticeable when the sub receiver is turned on, the sub volume is up, and tuning steps are set to fine. The noise ONLY occurs when I turn a VFO knob or filter knob. If I do not touch any knob, the noise does not occur. It does not matter if VFO A or VFO B knob is used, or whether or not they are linked.
So think of it like this: when I am in that band area, if I continuously turn a VFO knob, I will hear the motorboat noise until I stop turning the knob. If I pass that particular frequency area, the noise disappears completely. Also, I am using beta firmware 2.82. When I am tuning around with the sub receiver's VFO linked to the main, if I encounter a band edge, I hear a relay click and then the difference between both frequency counters can be anywhere from 500-900 KHz apart. In order to get them to match, I have to press A/B then A > B to duplicate the frequency. 73, James KC2UEE -----Original Message----- From: Matt Zilmer [mailto:mzil...@verizon.net] Sent: Sunday, February 22, 2009 5:54 PM To: James Sarte Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] Strange behavior when tuning around with SUB receiverLINKED James, What rev of firmware are you using? I went through test on all of them I could with the subreceiver, which I didn't install until 2.72 was current. I can't duplicate your results with 2.82. It may not be a firmware-related issue (or issues). In the first problem statement, it sounds like you have the VFO's linked. Are you also in DIVRSTY or not? As I understand it, the spectrum covered is carved up into band sections, each allowing the VCO control voltage to traverse a good part of its control range. Very few (if any?) of these breaks is within a ham band. The behavior you described at 5997 could be tied to the down-tune break at that freq. The up-tune break is 5 KHz or so higher. You might want to see if you can repeat this tuning up as well. I can't duplicate this problem here with 2.82. If there is a real bug here in the FW rev you're using, it *ought* to affect tuning in both directions. For your second problem statement, the following may apply. There is a chirp radar between 5184 and 5212 KHz (approx). The chirp goes through the passband pretty quickly, maybe within 150-200 mS and the rep rate is a little under one second. It's a wideband signal, and you may be hearing it as a zipper-like noise. You didn't say whether or not you heard it as a repeated or continuous signal, so I can't be sure this is what you're describing. 73, matt zilmer, W6NIA ______________________________________________________________ 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
