--- In [email protected], "kc0vkn" <[EMAIL PROTECTED]> wrote: > > Hey group, > I've got an older 6.1-Lite that I've been fussing with on 30M with > CW Skimmer. > > I'd had it up a few hours when someone notified me my spots were > off. I started looking more closely (and I hadn't noticed it in > Rocky) that I was seeing mirror signals on either side of the center... > > I've just now had time to investigate further and: > > On the Audio side, I have signal on both L/R-T/R. If I go to the > center of the board and look for the square waves, I see them at about > 90 out of phase, but they are rather ugly looking square waves. > > Just jumping back and forth in Skimmer, I find that the "correct" > signal is a bit louder than the image, but, both are enough for > skimmer to pickup. > > What is the correct Q/I relationship< Q=Right, I=Left, or the other > way around? > > I've got T/R correctly connected going out to the PC, but: Skimmer > settings are are Q=Left I=Right in order to see things where I think > they should be (eg: stronger sig on the low side of the center; as > confirmed with my big rig). > > Anyone have any ideas where I should look? > > 73, > > Joe, KC0VKN >
Hello Joe. I typically plug the connector in such that the red wire goes to the Q, and the white to I. But, I doubt that a reversal is your problem. If the only problem was that the two wires are reversed, you would still get virtually no images, but the spectrum would be backwards. This means that as you tune a signal generator up in freq from the bnottom of SR coverage, you would see the signal start at the TOP of the display and work otself down, instead of starting at the bottom and going up. Images can be caused by a whole host of issues. What type of sound card are you using? Not a laptop with the internal sound card I hope. Several Sound Blaster type sound cards typically need an I/Q delay of at lease one sample. Make sure your sound card and software is in line-in mode, not mic in. Mic in is typically mono, and you will not get image rejection. Make sure the stereo balance on the Windows mixer is centered. Make sure your audio cable is actually sending stereo (I/Q) into the sound card. I once had a radio shack cable that was poorly made, and only one channel got to the sound card. There are other potential gotchas, depending on the sound card used. I'm also a little concerned about you seing a square wave on the audio outputs, they should be sine waves. With a fairly strong signal fed into the SR Lite, you should see two fairly clean sine waves coming out the audio, with one lagging the other by 90 degrees. The frequency of those sine waves should be equal to the center frequency minus the RF carrier (or the other way around). For example with a center freq of 7.055MHz, and an RF freq of 7.057MHz, you should see an approx. 2,000 Hz audio pair, with one leading the other by 90 degrees. Good luck. Terry WB4JFI
