I made a 2 meter colinear based
on the same design that I later found on your website. I'm a machinist
by trade, so I made it from stainless steel and Delryin platic. I thought
you might be interested in a pic (attached). I find that it works quite
well for FM simplex out to about 60 miles from my base station to a mobile
station. It's only up about 17 feet at the feedpoint. I enjoy building
antennas and use only homebrew antennas other than a comercial 10 meter
antenna I have up. Anyhow, I just thought you might like to see a pic.
Take care, Mark/AC7AZ.
Hi Mark,
Thanks for checking out the Hampage.
Kim and I have a lot of fun doing this Web project together.
Reengineering j-poles is great stuff.
We did this section on the 2-meter j-pole from 450 ladder-line in hopes
to get others interested in building homebrew antennas. Like the
j-pole, this collinear configuration has been around for some time.
450 ladder-line is easy to work with and short cash. Turns out to
be a good product for modeling VHF antennas. Everyone seems to have
a short unused roll of it collecting dust someplace in the shack.
The best idea we came up with was the addition of a so-239 for easy separation
of the coax. Ref: http://home.comcast.net/~buck0/ll5coolj.html
Works out great this way for portable emergency communications applications.
Not sure if it's truly a new idea? But, perhaps a new spin for VHF..different
and fun..
Your fixed antenna from stainless
looks really slick!! Thank you very much for sending us the image!!
I see you used a coax matching balun in this design. Interesting
stuff!! Can you please send more info in this balun idea? Also,
is it okay to post this message you sent, and the image on the Hampage?
We will start a new comments section for this. Totally up to you..
If not, that's okay too.
Thank you!
73,
Steven
W. Merrill, KB1DIG
Emergency Coordinator
Amateur Radio Emergency Service
Strafford County, New Hampshire
http://www.w1fz.org/ares
603-749-3170
Hi Steven, Sure you can post the message I sent. I found
an online coaxial balun calculator, although I use my analyzer to trim
mine to the desired freq. Let me see if I can find it for you. I like to
play with antennas. I attached a picture of the colinear Super J-pole antenna
I use on my garage station. I also made up several 5/8 wave groundplane
antennas that a few of us use mobile here in Phoenix. I haven't found an
antenna to beat it yet for mobile use. I'll send a picture of one seperately.
I made a big 2-meter corner reflector too, I'll see if I have a pic of
it on disc somewhere. Keep in touch, Mark/AC7AZ.
Here's the link for the balun calculator and a picture
of a 5/8 wave too.
Click
here: 4:1 coax balun design.
Hi Mark,
WOW!! Great stuff!!
Thank you for the quick reply!!
I'll save all your contact info
and all the images and post something in a week or so. You could
get some e-mail from others intrested in your antenna ideas. I know
we have (not a bad thing). A lot local happenings now.. Ref:
http://www.w1fz.org/ares/k1stf_net.html
This new EC stuff keeps me hopping. Will send you a message and a
shortcut link back, to let you know when it's finished.
That's the one things I don't have
at this QTH.. an antenna analyzer. I really need to get me
one of those things...;-) Will help us cut down on the number of
project rejects too. But, for us, it's only wire..hi hi.
73,
Steve
KB1DIG
Cool beans. By the way, I made the 2 Yagis in the background
of the 5/8 wave photo too. Mark.
I hope you're not getting tired of these e-mails, but
I found some more pictures I thought you might find interesting on my old
computer. I'll send them as a zip file. One is the corner reflector I made
for a friend of mine, I used a t-match. Another is a closeup af a hairpin
match I used on a six meter antenna I made for another friend. I got the
plans from the ARRL Antenna book for that one. And the last one is a closeup
of the coil form etc. of a 5/8 wave. I have several of these forms made
up and I'd like to send you one to play with. You'll need to get 4 #6-32
nuts for the radials, 1 #10-24 nut for the radiator adjuster, and 2 #8-32
set screws to hold the radiating element in place. I would recommend getting
stainless steel, they'll all cost around a nickel each. You'll also need
a couple of eylet type solder lugs to attach the coil wire itself to the
radiating element adjuster and to the groud radial ring. Than its just
a matter of tapping the coil for impedence and trimming it to length for
SWR. I tap the coil with the center conductor of the coax at the 4th turn
down from the top, and attach the shield to the ground radial ring. That
will get you close. I'll see if I can find a long enough tube to ship all
of the elements in and get back to you. I assume your address is good on
QRZ? Take care, Mark/AC7AZ.
These are some of the iambic paddles I make too. Mark.
Hi Mark,
Come to think of it, I read about
these exact same paddles you made on eHam.net. This is art!!
Passion!!! Truly amazing stuff!!
Thank you very much for sharing
these images.
Net time in 30 minutes and I'm doing
net ops...got to run..hi hi
Be good!
73,
Steve
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