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lilrojo
11-09-2014, 10:57
Trying to start a HF Base-station for the partner nation on my current deployment and I am having trouble finding a suitable Antenna the is Omni directional and that can receive and transmit traffic at a Maximum of 500KM. I've unsuccessfully attempted the cobweb antenna and I am going to try a few more. If anyone has used anything in the past it would be greatly appreciated. Also if anyone knows what the setup is to use Harris Tac Chat on data.

Hartley
11-09-2014, 12:32
We have had medium success with various brands of "T2FD" [tilted terminated folded dipole] antennas - installed either tilted or as an inverted vee, it is fairly omnidirectional. Examples include the B&W 90 (and 180), or the Buxcom 1606T2FD. Buxcom also sells the tricky parts so you can build your own.

The 90 foot version cuts off performance-wise at about 4 MHz, so if you want it to work below that, use the longer ones (the SWR is fine down to 2 MHz, but performance is awful).

Buxcom also sells a terminated loop antenna (84216KIT) that strikes me as an excellent idea, but I don't know anyone who has tried it.

Hartley

lilrojo
11-09-2014, 17:45
Trying to build on to show them how to make one from the basics. Tomorrow I am going to attempt a Multi Dipole using some frequencies i got from http://www.ips.gov.au/HF_Systems/6/6/1. Going to do 4 legs and see how it works. Also using a Ugly Balun at the feed point to go into their 5800 MP. Ill try the ones you suggested to see if they work here. TY

Hartley
11-09-2014, 23:04
Hi,
Multi-dipoles work fine as long as the freqs are not harmonically related - keep in mind that you will probably have to trim them to slightly different lengths from the calculated ones as they do affect each other.

FWIW, the State Dept. uses a lot of T2FDs on their consulates and embassies - no trimming or expert calculations involved..:)

If you can get 'em to buy an auto-tuner, there are lots of possibilities.

Hartley

glebo
11-10-2014, 16:56
Have you tried the good 'ol AS 2259 NVIS antenna that came with the PRC-104?? Depending on location, ground conductivity blah blah, (I'm' sure you know this) that antenna may work well.. Also, how are you're freq's propping for 24/7???

Also, as mentioned above, depending on freq spread and harmonics, a couple of fan dipoles, (oriented in different directions) which I think you've tried.

But, it's all about freq's and a good SOI to depict, depending on time of day...

good luck...

lilrojo
11-24-2014, 17:07
Thank you for the trip we go forward in a couple of days so hopefully this works we set it on az to the forward destination. Doing voice and data with the PN's 5800 series radios.

ZUG_master
11-25-2014, 06:48
Must be in the Southern Hemisphere....

69harley
11-25-2014, 08:16
Barker & Williams.

http://www.bwantennas.com/pro/bwds.pro.htm

Dalik
11-25-2014, 13:29
Do you still need help with tac chat? Are you using 150's?

lilrojo
12-10-2014, 21:53
Finished the OP and we talked 325KM using the Mutiband Dipole and the MSS using a HF Dipole. Worked with Voice and Data 5 by with the use of the 5800 MP Harris radios and Tacchat. We were able to send pictures and data back to the partner nations Base station so I would call this a success. The price cost us about 19 dollars for all materials vs over 1k to buy some expensive premade antenna. Def making it harmonic on the base stations end helped allot.

Hartley
12-10-2014, 22:15
Congratulations!

helicom6
12-11-2014, 02:09
Trying to start a HF Base-station for the partner nation on my current deployment and I am having trouble finding a suitable Antenna the is Omni directional and that can receive and transmit traffic at a Maximum of 500KM. I've unsuccessfully attempted the cobweb antenna and I am going to try a few more. If anyone has used anything in the past it would be greatly appreciated. Also if anyone knows what the setup is to use Harris Tac Chat on data.

Hello lilrojo;

I am having dinner with a Harris architect on Friday evening and will ask for some feedback on your request. If you want to PM me I do have some information about the 150, including antenna suggestions.

Helicom6, Out

helicom6
12-11-2014, 02:12
You could always start here!

http://rf.harris.com/productaccessories/?pid=9455

Hope you are finding what you are looking for!

Cheers!