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  1. groundhog1

    Measured a CP antenna and linear good, CP pattern bad.

    Thanks for the tips on seeming brilliant! I often hear wonderful complements like " oh yeah... you're a freakin Genius" So your suggestion should only enhance the effect I have on people. groundhog
  2. groundhog1

    Measured a CP antenna and linear good, CP pattern bad.

    Thanks Bill. The rectangular patch with the probe feed on the diagonal (almost) is a very common CP design. They radiate on all four edges rather than the two for regular patch antennas. Also, in my lab with the network analyzer, using two of these identical antennas, I am getting good RHCP...
  3. groundhog1

    Measured a CP antenna and linear good, CP pattern bad.

    The antenna radiates RHCP. The ground plane is not much bigger than the patch. Substrate er=10. At the network analyser in my lab, I used two bare antennas. I rotated 360 degrees or more. What you see in the S21 display is like a wave in the ocean when you rotate it, with the center fo point...
  4. groundhog1

    Measured a CP antenna and linear good, CP pattern bad.

    I built up a plain rectangular patch antenna with the probe feed on the diagonal to set up circular polarization. Using my network analyzer, and putting itentical antennas on both ports, everything looks fine to me. I can rotate the antenna and at center freq, the insertion loss between the...
  5. groundhog1

    Patch ant with both Left and Right Circular polarization?

    Higgler, Are you saying that it can be done simultaneously or are you saying you can pick one or the other in a switching action? I mapped out the currents on the patch and fields in space, and they seem to cancel in the simultaneous case. But then I talked to a friend at work with a much...
  6. groundhog1

    modeling question on basic CP square patch..

    So as not to confuse.. This is all in simulation. There is no hardware at this point. gh
  7. groundhog1

    modeling question on basic CP square patch..

    Hello, I am trying to make a standard almost square patch with probe feed, where the feed is kind of along the diagonal of the patch. To simulate/measure axial ratio, I put in a very small pickup dipole element with impedance of 377 some distance from the antenna under test (AUT) face. Then I...
  8. groundhog1

    Patch ant with both Left and Right Circular polarization?

    Thanks VE1BLL for the tip. I mapped out the fields on a patch and as you suggested, and it looks like you get linear polarization (or total cancelation depending on how things are phased). groundhog
  9. groundhog1

    Patch ant with both Left and Right Circular polarization?

    Is it possible to do a patch antenna with both Left and Right hand circular polarization? Say you had a square, probe fed circular patch antenna. You put the probe feed somewhere on the diagonal to match and create the circular polarization. What if you put another probe on the other diagonal...
  10. groundhog1

    My first VBA Excel program doesn't port to new computer..

    I thought of this later, but shouldn't I be able to go to the references and just unclick those items? I did create bmp cartoons of the test setup in Visio, but I don't see why the spreadsheet really needs those dll files. groundhog
  11. groundhog1

    My first VBA Excel program doesn't port to new computer..

    Yes that did it. My fight-or-flight panic response is going down now. It needed some Visio dll files. I have Visio on my desk computer, but not on the mfg machine. Thankyou, groundhog
  12. groundhog1

    My first VBA Excel program doesn't port to new computer..

    Yes, it seems I am missing some Visio dll files. It shows missing VIsio 11 type missing Visio 11 dwg cntl They reference dll files and i will put them on the new computer.
  13. groundhog1

    My first VBA Excel program doesn't port to new computer..

    I developed my first Excel program and it works great on the computer on my desk. Last night I tried to run it on the manufacturing computer and it has a compile error. I can't totally remember the error message and I am not at work right now, but I will update this post shortly. It make me...
  14. groundhog1

    Thankyou...

    I want to thank you all (joerd, johnwm.. ) for your help and suggestions. My little program has chugged through it's first real production unit and all I saw was pass, pass, pass... Still some improvements to be made, but it is pretty much a useful tool now. Thanks. I have thrown in some...
  15. groundhog1

    VBA variables that exist over all modules? And file saving.

    joerd, do you have a sample of the code you are describing to put a name to a cell location? Is it as simple as: Variablename = Cells(1,1) thanks, groundhog
  16. groundhog1

    VBA variables that exist over all modules? And file saving.

    1.) Is there a way to create a variable that lasts forever and is usable over all modules? My code is in several modules and I want several things to be constant, like the serial number of my unit under test and maybe the partnumber. Stuff like that. Right now I am just reading it off of the...
  17. groundhog1

    How much power can microstrip handle?

    Do you see any benifit of using for example, stripline versus microstrip? Microstrip of course is a ground plane on bottom, dielectric layer, and then signal trace on top. Stripline is ground plane on bottom, dielectric layer, signal trace, dielectric layer again, then another ground plane on...
  18. groundhog1

    What does this mean..?

    Yes thanks. I am starting to figure this out a bit. The SICL part is the worst. Seems complex. But i am getting data from the network analyser now. So that is not so much an emergency now. I am into the Basic programming stage at this point and now realize that i am not such a good programmer...
  19. groundhog1

    What does this mean..?

    I am in excel learning to use VBA so that I can simply try to get a marker value from an Agilent network analyser. I have one of their .xls examples and it does all kinds of things to the analyser, but I can't seem to figure out how to modify the darn thing! THe analyser is on the network...
  20. groundhog1

    How much power can microstrip handle?

    The 100-200 watts is only passing through the board, being transported. It is not being dissipated totally. But on the max power that can be carried on microstrip, I see what you are saying and it makes sense. I just don't know what the actual number of watts that typically can be passed...
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