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KF5BET
07-12-2014, 10:01 PM
My good friend Glen, KF5FNP, has an article in the August edition of QST magazine describing his portable antenna for his Go Kit. It is a Tape Measure Vertical (TMV). I can see this antenna as being a very good option while camping as long as there are trees near your setup (or a portable mast).

I constructed one of these TMV's and hung it up in a tree in the back yard. All together I think it cost me about $10.00 I had a lot of stuff in my junk box and you probably do too!

The premise of the antenna is to use a 25' tape measure and a heavy duty tent stake. Install a stud through the end of the tape measure and connect the center of a SO 239 attached to the tent stake to the stud. Haul up the tape measure to the required height for the desired band. Use 4 1/4wave radials per band attached to the ground lug of the SO 239 and stretch out the radials at 90 degree points on the ground. Fine tune the antenna by raising and lowering the tape measure until the lowest SWR is found (I used trusty old MFJ 259B). Use a rope tied to the tape measure that is marked for the appropriate band, just raise the tape measure until the mark for the band is touching the ground, then fine tune using an analyzer or SWR meter on the radio.

I built radials for 10m, 15m, 17m and 20m. I still have to make the tuning rope, but have the dimensions (got Kendra to help me raise to lowest SWR on each band and she used binoculars to read the tape measure since I have "old" eyes).

The antenna tuned to 1.0 on all but 20m and 1.2 on that band.

Made a couple of contacts and confirmed it was working.

Take a look and maybe it would be a beneficial addition to your storage compartment.

N3LYT
07-13-2014, 05:17 PM
OK I guess you are saying you start at zero inches with the feed line and haul the body of the tape up? So what happens to the left over tape inside the roll doesn't that added to the overall length? Maybe it does not matter because you tune it to length any way.

NN5I
07-13-2014, 05:40 PM
So what happens to the leftover tape inside the roll? Doesn't that add to the overall length?

The leftover rolled-up tape will not add to the electrical length.

A pity, that. If it would add to the length, I could fit a full-size 160 meter dipole in a coat closet, simply by rolling up the ends.

KF5BET
07-13-2014, 08:58 PM
Yep that's correct you hoist the tape measure body up and fix the end (0") at the ground. I used short pieces of cord to make a sling around the tape measure for hauling it up.

W9WLS
07-14-2014, 05:07 AM
Many years ago, COLLINS RADIO had a version of this as a "DIPOLE" in one of their "FIELD KIT'S" , had a coax connector and two 100 foot steel tapes mounted on a insulating board.
You pulled the tape's out to the required length , locked them in place and hauled the thing up a tree or whatever, stretched out the tapes and secured them and you had a temporary DIPOLE.
If I remember correctly "B&W" had a version (they might have even made the one in the Collins Kit) and a bit later "HY-Gain" marketed one.

wa8yxm
07-14-2014, 08:24 AM
While the idea looks good.. I like 80 and 40 meters, I do have a 100 foot tape (might work with a tuner on 80) but tree limbs 62.5 feet up are
1: rare
2: Hard to toss the pull up weight over.

What I use is currently fifty feet, but normally 83 or 83 feet of wire (14ga) with around 50 feet of nylon (make sure it does not have a wire core) grafted on the end and 2 pound concrete weight on the end of that.

David and goliath method is used to "Slingshot" the weight over a tree, I can routinly hit 20-30 feet, I use a fishing pole (Telescoping) at the RV end if needed

To make weight: Get some sugar free powdered drink mix, Wylers, Crystal light, Store brand, that comes in a paper or plastic "Tube" usually 5 packages to a tube.

I make weights two ways,, Since I have a lot of extra cable I fill em with concrete mix and shove some aircraft steel cable into them, You can also use an eye bolt (I like to leave the nut on) Let harden, and add a clip (or there are ways to loop the rope over.

A shorter length of nlyon anchored a few feet from the other end lets me tie the line off so as to provide strain releave and a common crimp on terminal lets me attach it to a Kenwood KAT-1 Auto-tuner


Current 50 foot wire is used due to lack of trees.. I "Plant" the drive on base for my flag pole under a front tire,,, And.. Run the "Far" (Tree) end of the wire up the flag pole, 50 foot on this RV is a perfect length for doing this.

NN5I
07-14-2014, 10:24 AM
Many years ago, COLLINS RADIO had a version of this as a "DIPOLE" in one of their "FIELD KIT'S" , had a coax connector and two 100 foot steel tapes mounted on a insulating board.
You pulled the tape's out to the required length , locked them in place and hauled the thing up a tree or whatever, stretched out the tapes and secured them and you had a temporary DIPOLE.
If I remember correctly "B&W" had a version (they might have even made the one in the Collins Kit) and a bit later "HY-Gain" marketed one.

The Hy-Gain Tape Doublet works well. I've had one for many years and use it sometimes. It's around here someplace.

N3LYT
07-14-2014, 05:15 PM
Yep that's correct you hoist the tape measure body up and fix the end (0") at the ground. I used short pieces of cord to make a sling around the tape measure for hauling it up.

OK that makes sense I have done the same thing but with measured wire for the band. Concept behind the StepiR.

KF5BET
07-14-2014, 09:08 PM
OK that makes sense I have done the same thing but with measured wire for the band. Concept behind the StepiR.

Exactly!

W7JZE
07-17-2014, 06:08 AM
While the idea looks good.. I like 80 and 40 meters, I do have a 100 foot tape (might work with a tuner on 80) but tree limbs 62.5 feet up are
1: rare
2: Hard to toss the pull up weight over.

What I use is currently fifty feet, but normally 83 or 83 feet of wire (14ga) with around 50 feet of nylon (make sure it does not have a wire core) grafted on the end and 2 pound concrete weight on the end of that.

David and goliath method is used to "Slingshot" the weight over a tree, I can routinly hit 20-30 feet, I use a fishing pole (Telescoping) at the RV end if needed

To make weight: Get some sugar free powdered drink mix, Wylers, Crystal light, Store brand, that comes in a paper or plastic "Tube" usually 5 packages to a tube.

I make weights two ways,, Since I have a lot of extra cable I fill em with concrete mix and shove some aircraft steel cable into them, You can also use an eye bolt (I like to leave the nut on) Let harden, and add a clip (or there are ways to loop the rope over.
A shorter length of nlyon anchored a few feet from the other end lets me tie the line off so as to provide strain releave and a common crimp on terminal lets me attach it to a Kenwood KAT-1 Auto-tuner


Current 50 foot wire is used due to lack of trees.. I "Plant" the drive on base for my flag pole under a front tire,,, And.. Run the "Far" (Tree) end of the wire up the flag pole, 50 foot on this RV is a perfect length for doing this.

At Home-Depo I stumbled across what are called "Doobies" or sometimes "Dough-bees". These are little concrete blocks about 3" x 3" x 3" with a loop of wire embedded in each one. They are used when contractors lay re-bar down. They are like little temporary anchors to hold the re-bar in place until the wet concrete is poured over the whole mess. I put 3 or 4 together with a cheap carabineer (about $1.00 at Home-Depo) and use it for a counter weight on my home QTH dipoles.

When the sun comes up I'll take a pix.

The "Doobies" are CHEAP at Home-Depo! I think they might have been just $0.25 or $0.50 each.

Edit: 8-2-2014:
I guess the sun finally came up :jitter:. I even took the pix. Then I forgot to upload. Anyway... Here are the cheap, Home Depo "Doobies"...
.

megahurst
08-01-2014, 05:25 PM
Been thinking of a way for those of us with somewhat limited eyesight to know the length of the tape. Am considering spray painting sections of the tape measure in different colors, one color per band.

Just an idea but should serve the purpose - easier initial setting of length.:rv:

NN5I
08-01-2014, 06:20 PM
Interesting, Megahurst. Or you could dimple the tape so you could feel the dimples. A dulled center-punch could do that. Sort of like simplified custom Braille. But it might make it hard to roll it up if the dimples are too large.

WA6CDE
08-02-2014, 01:30 AM
Many years ago, COLLINS RADIO had a version of this as a "DIPOLE" in one of their "FIELD KIT'S" , had a coax connector and two 100 foot steel tapes mounted on a insulating board.
You pulled the tape's out to the required length , locked them in place and hauled the thing up a tree or whatever, stretched out the tapes and secured them and you had a temporary DIPOLE.
If I remember correctly "B&W" had a version (they might have even made the one in the Collins Kit) and a bit later "HY-Gain" marketed one.

Indeed they made one at hygain also... had one.. kinda heavy thought... but their was a article in EHAM on how to build one. I think the bigger problem is the left over tape measure inside the reel.. causing inductance.. several were made using fishing fly reels also with some of that flex wire. Here is the article http://www.eham.net/articles/16944 but a better one is this one that is much lighter http://www.eham.net/articles/7949
Good luck as we found that a good ICOM AH4 and 65 ft of wire ...along with a ground works great on our ICOM 7000 just about anywhere:radio::2cents:

KF5BET
08-06-2014, 12:21 AM
My buddy took a length of para cord and used marking tape of some kind at each desired length. When hauling up the tape measure, run it up until the marker just touches the ground and you're at the correct length.

NN5I
08-06-2014, 01:08 AM
Or maybe just pull it out to the required length while it's on the deck, and then haul it aloft.