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RE: Mars Antennas
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by KA1MDA on June 26, 2008
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"A very popular option is the B&W Terminated Folded Dipole"
I wouldn't wish this antenna on my worst enemy! I have one, got it for free from someone that was getting out of MARS. If I include the time and labor to install it, I feel I overpaid. It's totally deaf. Compared to my 2nd hand Hustler 6BTV, stations that are S-0 to S-1 on the B&W are S-7 to S-9 on the Hustler. I couldn't even hear the HARP experiment on 7 Mhz with that lame antenna. If you have a KW, and want to work a few hundred miles, I guess it's ok, but there has to be a better choice! The day I replaced the B&W with the Hustler was the first time I could ever turned off the preamp on me receiver and still hear something!
73, de Tom, KA1MDA
www.ka1mda.org
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RE: Mars Antennas
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by K3WVU on June 27, 2008
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Tom,
I think you're missing the point here. You're quite correct about the B&W antenna if your primary purpose is working DX. For MARS, it is a very good antenna, because most MARS HF comms are local or regional. The B&W antenna is also capable of working over a wide range of frequencies that a non-MARS ham never uses, which is a paramount concern for MARS. Your Hustler 6BTV, with a good radial system, is great for DX, but would be nearly useless for most MARS work.
73
Dwight NNN0TPR/NNN0GCP2
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RE: Mars Antennas
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by W3LK on June 27, 2008
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<< I wouldn't wish this antenna on my worst enemy! >>
No one asked you to. :)
Yes, tom, you missed the point.
For it's designed purpose, it's an excellent antenna. As a general purpose ham antenna, no. There is little else that is as frequency-agile and does not require any kind of coupler, as is often the case in military and MARS communications. I don't know how you installed it, but having use several over the years, I didn't find it deaf, by any means.
It's called using the right tool for the job - and for typical 100-200 mile MARS operations, your Hustler ain't the right tool - and neither is my Butternut HF6V.
I'm curious as to what MARS experience, if any, you have.
Lon - NNN0OOR (Former MDE SMD, Deputy SMD, Assistant For Net Operations)
Southern New England Navy-Marine Corps MARS
Proudly Serving Those Who Serve
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RE: Mars Antennas
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by AB5KT on July 24, 2008
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W3LK,
I read your post about asking people about their MARS experience and with your three line signature block, I am almost afraid to ask a question.
Then what would be a good antenna recommendation for those of us who do not have many years of MARS tucked under out belts?
Educate rather than tear people down!
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RE: Mars Antennas
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by W3LK on July 24, 2008
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I don't understand your comments, but if you are referring to my response to Tom, the man simply doesn't know what he is talking about. He has made the same statements in other forums and has been shot down by several hams who DO know what they are talking about.
The best antenna for MARS is a dipole cut to the specific frequency you plan to operate on, but if you operate on several, as most MARS members do, that's not very practical.
Just about any multi-band dipole and a wide-range tuner will do. That's what most MARS members use. If you don't want to use a tuner, the B&W is a good choice, albeit it is down 4-6 dB from a single-band resonant dipole.
Verticals are a poor choice for state-wide or regional operations due to the low takeoff angle. What you need is the high takeoff angle of a dipole and even better is one in an NVIS configuration - 12 to 15 feet off the ground. I used one for a few years and did fine on the Southeastern regional nets but often couldn't be heard 20 miles away. In my present location, the B&W is 6-8 dB over my Butternut HF6V under three hundred miles.
I hope this answers your question.
Lon - NNN0OOR (Former MDE SMD, Deputy SMD, Assistant For Net Operations)
Southern New England Navy-Marine Corps MARS
Proudly Serving Those Who Serve
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RE: Mars Antennas
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by KB1RBF on November 5, 2008
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Thought I'd jump in here, as I just sent off an e-mail to the Navy-Marine Corp MARS HQ for application.
Good advice on the antennas. those were questions I had as well. Much appreciated.
-Gene KB1RBF
(Former Air Force. LOL!)
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RE: Mars Antennas
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by W3LK on November 5, 2008
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Welcome Aboard!
I look forward to hearing you on the Southern New England nets.
Lon - NNN0OOR (Former MDE SMD, Deputy SMD, Assistant For Net Operations)
Southern New England Navy-Marine Corps MARS
Proudly Serving Those Who Serve
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RE: Mars Antennas
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by WB2GBF on November 15, 2008
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There are a few options, as you've already seen. There's a good reference on the Army MARS URL at http://www.netcom.army.mil/mars/training/index.aspx .
I have used an inverted V with a manual tuner in the past. Currently, I use a window line fed doublet at 25' with an LDG AT200PC autotuner. It works very well. As you've already been told, stay away from verticals for the state nets. I'd also stay away from tuned dipoles as the wide HF frequency ranges would limit your operating possibilities.
Pat
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Mars Antennas converting a RM-80 for use in 4mhz
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by N8PHL on January 19, 2009
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has anyone ever converted a hustler rm-80 for use with MARS use?
i want to use it for mobile use as i have major CC&R's where i live.
any ideas that will help me get onto the 4mhz band would be great.
AAR5EA/T
N8PHL
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RE: Mars Antennas
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by KW9D on February 24, 2009
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For HF I have used a dipole cut for 2Mhz (about 240ft) fed in the center with ladder line. Then a 4:1 balun close to my window with coax feeding into my house. My FT-990 auto tuner will match it on all the Mars frequencies that I use. If you don't have room for an antenna this big, make it as long as you can with a goal of being half wavelength on the lowest frequency you need. Avoid using coax to directly feed a dipole operating far off a resonant frequency as the SWR will be very high and losses will be high also. Ladder line will work fine with a high SWR with little loss, except when it's wet. When my ladder line is wet it changes tuner settings but I don't notice the added loss in performance. You can also bring the ladder line into the shack and have a balun close to your rig. Voltages on the ladder line can get high so be careful about exposed conductors and small kids.
If you use a manual tuner record control settings for each frequency needed to make tune-up quick and easy. For the coax run from the balun to your rig use RG-213 as the SWR will be high on some frequencies. Also keep this coax run as short as possible to minimize losses. RG-58 is a poor choice due to loss at high SWR.
A 240 ft dipole will show some directivity depending on its height when operating on higher frequencies. Have a goal of 0.1 wavelength high for minimum loss on your most active frequency. (24 ft high at 4 mhz) An antenna significantly lower will perform adequately in all but the worst conditions.
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