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HF NVIS 101

  • 25 Oct 2017 7:16 AM
    Reply # 5348465 on 4968034
    Deleted user

    Good stuff. 

    One of the problems with NVIS is the conditions are not always the same and the charts have to be checked to see what would be the proper freq to use.  Right now in the middle of the Atlantic Ocean you could use up to 12Mhz but for So Cal it is only up to 4Mhz.

    I have a 16 foot whip and have tuned it with my screwdriver. I am not convinced that was doing what we think either straight up or bent over. I really would like it to work because it is easy to set up for me, but last test in the Sierras I don't think it was working via NVIS.

  • 26 Oct 2017 9:17 PM
    Reply # 5381214 on 4968034
    Chris Doering (Administrator)

    I apologize if this was already mentioned, but isn't there a chart the you carry around Rick? One that shows MUF? If so which one do you use? I find I am copying much of what you are doing.

  • 27 Oct 2017 7:21 AM
    Reply # 5388786 on 5381214
    Deleted user
    Chris Doering wrote:

    I apologize if this was already mentioned, but isn't there a chart the you carry around Rick? One that shows MUF? If so which one do you use? I find I am copying much of what you are doing.

    It is a website that is constantly updated. http://www.sws.bom.gov.au/Images/HF%20Systems/Global%20HF/Ionospheric%20Map/WorldIMap.gif
  • 05 Nov 2017 1:14 PM
    Reply # 5551055 on 4968034
    Anonymous

    Rick 

    I have a question on Chameleon CHA V2L antenna.  Would this work for mobile HF like the motorized antennas? Also looking at the CHA Hybrid with 14' whip over the vehicle for NVIS.

    Any comments or suggestion would help. Thanks


    Ric


  • 05 Nov 2017 6:04 PM
    Reply # 5553806 on 4968034
    Anonymous

    That Chameleon CHA V2L whip with the CHA Mini coil base is interesting, Ric.  You'll need an antenna tuner to go with it.   In the vertical orientation, it should work okay for DX when the skip in "in."  For NVIS work (inside 300 miles or so), having the capability to fold the antenna over close to horizontal, and re-tuned, may be necessary.

    I've been looking around and saw the CHA set, too.  I've also been looking at the 16'-17' whips that're used on the military rigs, bent over and tied to the front of the vehicle.  Of course, my truck is much longer than your jeep.

    Anyway, I think the CHA is a decent choice for something less mechanical (versus screwdrivers or Hi-Qs).

    Just some thoughts.  -Clint (NR6T)

  • 05 Nov 2017 9:03 PM
    Reply # 5555391 on 4968034
    Anonymous

    Thanks Clint, Its probably that route that Iam going to go. I do have a LDG tuner for my 857D. Iam interested in how the whip antenna in NVIS mode will hold up on the freeway. Guess only one way to find out lol

  • 06 Nov 2017 7:29 AM
    Reply # 5561375 on 5555391
    Deleted user
    Ric Dill wrote:

    Thanks Clint, Its probably that route that Iam going to go. I do have a LDG tuner for my 857D. Iam interested in how the whip antenna in NVIS mode will hold up on the freeway. Guess only one way to find out lol

    A tied down whip holds up just fine on the freeway. I will be doing some testing with my folded over whip at the HF Op this weekend and let you know the results. My guess is that it doesn't work as well as all the internet articles would have you believe.


  • 06 Nov 2017 11:19 AM
    Reply # 5564302 on 4968034

    Chris, Rick;

    I would like to participate in the Savahia Peak exercise this weekend, albeit remotely.

    Based on this, did you want me to mark down that I am attending, or no?

    Also I have two possibilities for you.

    1. I can take the jeep to a remote location and set up a G5RV for a couple of hours.
    2. I can take the truck, which has an ATAS-120 mounted, and I can be mobile for a couple of hours. (i.e. Start out in Riverside, Drive up to Big Bear, and Down to Lucerne & Apple Valleys

    Let me know which sounds more interesting to you.


  • 06 Nov 2017 2:15 PM
    Reply # 5566059 on 5564302
    Deleted user
    Donald Bower wrote:

    Chris, Rick;

    I would like to participate in the Savahia Peak exercise this weekend, albeit remotely.

    Based on this, did you want me to mark down that I am attending, or no?

    Also I have two possibilities for you.

    1. I can take the jeep to a remote location and set up a G5RV for a couple of hours.
    2. I can take the truck, which has an ATAS-120 mounted, and I can be mobile for a couple of hours. (i.e. Start out in Riverside, Drive up to Big Bear, and Down to Lucerne & Apple Valleys

    Let me know which sounds more interesting to you.


    I would say only mark that you are attending if you be onsite.

    I think you will have much better luck with the G5RV. We will be posting a schedule soon, but it will probably be mid afternoon and on 40 meters. I am thinking voice contact and then 30 minutes later Contestia Mode for those capable of digital. I am also open to CW if anyone wants to slow down for me.

  • 06 Nov 2017 3:14 PM
    Reply # 5566639 on 5564302
    Anonymous

    Rick Bean wrote:
    Ric Dill wrote:

    Thanks Clint, Its probably that route that Iam going to go. I do have a LDG tuner for my 857D. Iam interested in how the whip antenna in NVIS mode will hold up on the freeway. Guess only one way to find out lol

    A tied down whip holds up just fine on the freeway. I will be doing some testing with my folded over whip at the HF Op this weekend and let you know the results. My guess is that it doesn't work as well as all the internet articles would have you believe.



    Thanks Rick looking forward to the results 
    Last modified: 06 Nov 2017 7:14 PM | Anonymous
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