CAP Talk

Operations => Tools of the trade => Topic started by: Major Lord on November 18, 2011, 07:06:49 PM

Title: An 80 Meter Beam antenna
Post by: Major Lord on November 18, 2011, 07:06:49 PM
I wonder if Travis AFB would let us have a couple of acres of jackrabbit country to build a huge HF antenna? This thing is a 160 and 80 Meter beam antenna, perfect for the guy who can only run 100 Watts but still wants to communicate with Pluto on our 80 Meter ( Confidential- FOUO) frequency)

http://www.radioarcala.com/nbspStation/16080MMammothBeam/tabid/380/Default.aspx (http://www.radioarcala.com/nbspStation/16080MMammothBeam/tabid/380/Default.aspx)

Major Lord
Title: Re: An 80 Meter Beam antenna
Post by: wuzafuzz on November 18, 2011, 08:26:49 PM
Size matters. 

Darn physics.
Title: Re: An 80 Meter Beam antenna
Post by: Jerry Jacobs on November 19, 2011, 12:22:03 AM
Id love to have a toy like that trust me. I'm currently working on a VHF manpack solution though
Title: Re: An 80 Meter Beam antenna
Post by: PHall on November 19, 2011, 01:36:46 AM
Alan, doesn't the Navy have one of these over at Dixon? Maybe you could borrow it. >:D
Title: Re: An 80 Meter Beam antenna
Post by: Major Lord on November 19, 2011, 02:57:59 AM
Quote from: PHall on November 19, 2011, 01:36:46 AM
Alan, doesn't the Nave have one of these over at Dixon? Maybe you could borrow it. >:D

Hmmm, Ken Endrizzi lives out there....maybe he has a squid contact......

Title: Re: An 80 Meter Beam antenna
Post by: Major Lord on November 19, 2011, 02:59:04 AM
Quote from: Jerry Jacobs on November 19, 2011, 12:22:03 AM
Id love to have a toy like that trust me. I'm currently working on a VHF manpack solution though

Jerry,

What are you doing on a VHF manpack? I would love to see what you are doing!

Major Lord
Title: Re: An 80 Meter Beam antenna
Post by: brenaud on November 19, 2011, 09:51:57 PM
I'd settle for an 80m dipole.  (If all goes well I'll be able to in a couple of months, although given the lot size I'll have to get a little creative). 
Title: Re: An 80 Meter Beam antenna
Post by: Major Lord on November 19, 2011, 10:48:18 PM
I have tried a couple of verticals on 80 meters, but lacking space for radiators, I gave up. I am thinking about trying out this one: http://www.mfjenterprises.com/Product.php?productid=MFJ-1798 (http://www.mfjenterprises.com/Product.php?productid=MFJ-1798)  No radials required, and it will scare the bejeepers out of my neighbors when it suddenly appears over my house! Has anyone tried it?

Major Lord
Title: Re: An 80 Meter Beam antenna
Post by: Jerry Jacobs on November 20, 2011, 02:37:07 AM
Quote from: Major Lord on November 19, 2011, 02:59:04 AM
Quote from: Jerry Jacobs on November 19, 2011, 12:22:03 AM
Id love to have a toy like that trust me. I'm currently working on a VHF manpack solution though

Jerry,

What are you doing on a VHF manpack? I would love to see what you are doing!

Major Lord

I have a Motrola MT2000 that I bought and the plan is to attach an external roll up antenna to it and extend it as needed using a crappie pole or tent poles. The problem Im having right now is how to mount it to my backpack or vest in a way that will keep the antenna straight.
Title: Re: An 80 Meter Beam antenna
Post by: Major Lord on November 20, 2011, 02:57:42 AM
Jerry,

That's a good radio! Have you looked at the Smiley 1/2 or 5/8 wave antennae? These are 1/4 wave when shortened to the minimum, but 5/8 or 1/2 wave when telescoped out. They have springy base loaded coils to avoid snapping off ( You'll put your eye out!) My plan has been to use a small handi-talkie, in the 1/2 Watt range, to drive a 25 Watt amplifier and a telescoping antenna like the Smiley antennae. Batteries and the whole package to fit in a Pelican case, to fit in a rear or side pack pocket. With the unit switched off, it would pass your signal directly, but switch on the amp and suddenly you are a real radio station! ( Probably best not to switch on the amp and extend the antenna with the unit too close to your brain though.........) This is something we are considering manufacturing, and even though it would cover 135 to 175 MHZ, it probably could never be CAP-Kosher. Good for other Org's with ground-pounders though! I will let you know how the project is going. Let me know how your concept goes!

Major Lord
Title: Re: An 80 Meter Beam antenna
Post by: Jerry Jacobs on November 20, 2011, 06:11:22 AM
Wow I didn't see anything live that before when I was looking for antennas. That is EXACTLY what I wanted.

Your idea was something I was playing with but I think I read somewhere you can't amplify portables because they have looser restrictions on emissions. In a perfect world we'd just use HAM radio but we can only dream.

Sorry to hijack the thread btw

To get it back on topic I wonder how long the CAP safety briefing would be before climbing that tower
Title: Re: An 80 Meter Beam antenna
Post by: PHall on November 20, 2011, 06:40:11 AM
Quote from: Jerry Jacobs on November 20, 2011, 06:11:22 AM
To get it back on topic I wonder how long the CAP safety briefing would be before climbing that tower

Probably not that long since there are very few who are willing to free climb a 300 FT tower. :o

I know I won't do it. My comfort level stops at about 50 FT.
Title: Re: An 80 Meter Beam antenna
Post by: EMT-83 on November 20, 2011, 01:31:02 PM
After 50 feet, does it really matter? Will falling from a 10 story building make you deader than falling 5 stories?
Title: Re: An 80 Meter Beam antenna
Post by: Major Lord on November 20, 2011, 03:39:27 PM
Quote from: EMT-83 on November 20, 2011, 01:31:02 PM
After 50 feet, does it really matter? Will falling from a 10 story building make you deader than falling 5 stories?

It gives you a little more "hang time" to scream! I seem to remember the figure "30 feet" as the point of no return, but I have seen people just as double dog dead from falling off a step stool as from jumping off the Golden Gate Bridge. ( Although in truth, the bridge jumper was not a good candidate for an open casket service)  God seems to give points for better landing technique.

Major Lord

Title: Re: An 80 Meter Beam antenna
Post by: PHall on November 20, 2011, 04:12:58 PM
One thing I learned from the instructors in pole climbing school.
People with a severe fear of heights can't get past 8 feet (measured from your feet to the ground), i.e. the ceiling in a normal room.
Title: Re: An 80 Meter Beam antenna
Post by: Major Lord on November 20, 2011, 04:39:21 PM
Another CAP member and I took the instructor/instructor ( the factory training) course on the "Ropes" course at Camp SLO with the Army National Guard ( May they live forever in the halls of Valhalla) so we could be blessed as rappel-meisters for CAP. Although the ANG guys looked like they could tear Arnold Swarzenegggers' limbs off and beat him to death with them, at least half of them seem to have been chosen based on their profound fear of heights......In my view, a totally rational fear! fortunately, none of them reached the truly phobic threshold. As a "highly trained" ropes course instructor, I have learned not be afraid of heights....I am just afraid of falling! I just learned the rules as a matter of muscle-memory, so I can set aside the fear and concentrate on the climb... Mostly... I still get that tingle......I am sure Phil knows what I mean!