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mjohnellisis number911member,register2017-05-09 23:40




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    • Reply: VK3NH The theme of creating Minimising Port mismatch effects in S21 mode testing.

      Thank you Noel! This really helps me understand the KC901V better. Thank you for taking the time to inform us of the results - John 148 days ago
    • Reply: mjohnellis The theme of creating Some interesting things about KC901V.

      Noel, again you pointed out something of real value. When I first got the KC901V I tested a few filters that I had built for Ghz stuff, and I did the same thing, but I tried 3Db and then 6Db on each port hoping to reduce the S21 ripple but it didn't make a big difference. Later I tried one 10 Db pad on port 1 and then moved it to port 2. Again the ripple stayed about the same so I hope the ripple can eventually be fixed with a firmware update. Based on your comment, I will use at least 3 Db on each port to improve the match for S21 or would it be better to use 6 Db on just one port? Thank you again for some great comments. John 152 days ago
    • Reply: mjohnellis The theme of creating Some interesting things about KC901V.

      Hello Noel,
      Great information. I have also noticed the high ripple in S21 mode. To be honest, I was tempted to return the unit because it looks so bad, but the other features work so well I will I decided to keep it. It is good to know the fm modulation is spot on even to the point of agreeing with the Bessel null. You have done a nice job finding and explaining problems. I will try to add something useful as well, but for now I'm still learning VNA techniques. I have two HP 8569B spectrum analyzers, but I finally decided I need the phase information so short of buying another old 50 pound piece of equipment for several K, I decided on the KC901V. I am pleased with it, but as you pointed out, there are some flaws that may not be fixed through firmware. Again, Best Regards, John PS: Thanks for explaining how the comments work. 152 days ago
    • Reply: VK3NH The theme of creating KC951021 RF Demo Kit

      Thank you Noel,
      Excellent suggestion, I am looking into that now. I do have N to SMA adaptors so I should be good to go.
      Best Regards, John 153 days ago
    • Reply: BG8NPK The theme of creating Latest update KC901S/KC901V Firmware Update

      Thank you for new update KC901V. The skip Cal feature works fine now. 162 days ago