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HF Reel Type Portable Antenna for QRP

Marvin Hamilton (K9GDV) on April 9, 2004
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AN HF “REEL TYPE” HALF WAVE DIPOLE ANTENNA FOR PORTABLE LOW POWER USE

(OR A POOR MAN'S TAPE DIPOLE)

by K9GDV

My original madness

As most of us that have gotten bit by the “portable” or “qrp” bug in recent years, I have tried a variety of the “off the shelf -portable” antenna's to different degree's of success. The “old standby” half-wave dipole, very hard to beat. As it is the “old work horse” for dependable operation.

Some of the “Off the shelf“ portable antennas seem to work well, but have their limitations. Since acquiring several low power rigs, (the latest being the Icom 703 plus) I wanted to have a portable dipole antenna that could be used with a low power rig, and have the ability to cover more than one band, without carrying too many parts & pieces to get lost.

Some of you will remember the factory made tape dipoles that were produced by Hygain, or Collins that were easy to field deploy and carry. Tape dipoles could be setup for the desired frequency by pulling out the tape to the proper length and hanging them up. They are rather rare item now, as they haven't been produced for several years.

The Army had an antenna for the PRC-77 that used a Fly fishing reel to hold the wire, designated as an AT-984/G. Having recently seen one of them planted a seed in my mind. My usual portable dipole antenna consisted of coax cable, center insulator, and several pre tuned rolls of antenna wire for whatever band I chose to use. This was a bit awkward, due to numerous items to be carried. It would be nice to have a single package half wave dipole antenna that could be used on multiple bands, without carrying separate roll of antenna wire for each desired band, have the guy ropes and support rope all as one item, plus permanent frequency markers on the wire for desired bands.

0x08 graphic

How to mark the antenna wire, with a permanent non-slip marker, so that fairly dependable frequency repeatability could be obtained? I found that non-insulated metal ferrules, available from Digi Key, slid over antenna wire during assembly and later crimped into place during tuning of the antenna, when desired antenna resonance point was located, would provide a permanent marker, and wouldn`t slip. Fair Radio Sales has surplus Dipole antenna fixture (Originally for a PRC-74 by Hughes) that would do as the center insulator and main body for this project. Next thing found from Wal Wart was the Martin Model 61 reels (Chinese made inexpensive ones) They slid over the Dipole fixture frame perfectly. Just remove the 4 screws that retain the reel plastic mounting foot, and discard the plastic foot. To mount reels to the frame hold reel and dipole frame together, (look on face side of inner ring on reel - where bobbin fits- and insure that you don't have reel assembly slid too far in towards frame rail, or you won't be able to reinstall the bobbin onto reel assembly.) Then align and use the 2 existing holes on reel to mark dipole fixture, center punch and drill holes completely through fixture for a #6 x 1-¼ machine screw and mount reel to fixture.

I used surplus “push terminal” connectors, but one could use brass machine screws and wing nuts instead (use 10-24 threads) These are the dipole feed line to antenna wire connectors. (The push connectors also were from Fair Radio Sales and have a good grip and won't allow antenna wire to slip.)

0x08 graphic

25 feet of RG-174 coax cable was used to replace the original 72-ohm twin lead that comes with the Dipole fixture from Fair Radio. (Yes- it has some loss.)

The Reel bobbins will hold about 36 feet per reel of #14 gauge flex weave wire, so you will probably have to settle for 40 meters as the lowest operating frequency, rather than 80 meters, which can be obtained if using a smaller gauge of antenna wire. (Fair Radio also has small quantity of bare Phosphor Bronze “Gibson Girl” antenna wire in approximately 300 ft reel, which may be a bit tangled up-if you are fortunate enough to get some of this wire the two fishing reels will hold enough of this wire to operate down to 160 meters) I used Fishing Snap swivels on ends of the antenna wire for quick connection to the PVC pipe insulators on the support ropes. Before attaching snap swivels to ends of antenna wire stack 9 to 15 ferrules on each antenna wire to crimp at resonant frequency point during initial tuning of antenna

.

Tuning antenna

Measure out the length of wire, as calculated for half wave antenna, for the desired lowest frequency as a starting point and then use an SWR HF antenna analyzer, or SWR wattmeter and your transmitter to “tweak” the antenna to the desired resonant frequency. Be sure to begin at the lowest frequency you wish the antenna to operate (maximum antenna wire extended) at and work your way higher in frequency from there. Once you have the antenna tweaked” to the selected frequency, slide a ferrule up to the point of contact of the antenna wire and the dipole terminal connection, and crimp it in place. (One for each terminal connection) Then proceed to the next desired higher frequency and repeat the operation. After finishing placing the marker ferrules on the antenna wire you can pull out the antenna wire to the appropriate frequency marker ferrule, place the antenna wire in the terminal connector, and have a fairly accurate repeatability for resonance at the selected frequency. (Resonance point may vary a bit, from either side of crimped ferrule marker, depending on different installations of antenna height and soil conditions ) Oh! You better write down what frequencies you have placed ferrule markers at and keep list with antenna. (May want to color code ferrules also with DOB's of various colored paint)

If you use small size antenna wire, this antenna should only be supported using the center insulator, (Inverted “V”) as the wire may not be strong enough to hold up the entire arrangement. (#14 size wire should not be problem).

The next Reel dipole antenna I'll try adding a small, lower power 1:1 balun to it and see how that works.

The coax, support ropes and antenna wire are all carried on the Dipole “H“ frame center insulator, as one item, instead of separate pieces, which was one of my objectives in this project. To use the “reel” dipole, unwind the support ropes & coax from the dipole frame and reel off the amount of antenna wire to the ferrule marker of the band you wish to operate on, attach the antenna wire into the “connector” terminal, pull up the dipole frame center insulator to desired height in tree, or other support, string out dipole legs and tie off ends, hook up coax to transceiver and you are ready to go on air.

0x08 graphic
9

On air tests were run on 40 meter SSB, 20 Meter PSK and 17 Meter SSB using an Icom 703 plus at 5 watts and 10 watts. With resonate dipole the built in antenna tuner was not needed. As with any dipole, the frequency can go +/- of the center frequency somewhat without SWR going to high. No comparisons were made to other dipole antennas. This antenna was initially tuned as an Inverted “V” with center insulator relatively low to the ground. (15 to 20 feet) Ends of dipole were about 2 to 4 feet above ground. I suspect in this configuration there may be some NVIS antenna characteristics involved, as stations contacted on 40 meters were 100 to 500 miles away, and they gave me a decent signal report. On 17 meters stations several hundred to 1000+ miles away reported good signals and the same applied to 20 meter PSK.

The “Reel” dipole was not designed for permanent installations, but you should have no problems with it if left up for short period of time, such as field day, or even for a week. If you are true backpacker, the #14 Flex weave wire is a bit heavy and you will probably look for smaller gauge wire, to lighten the load a bit. Maybe you'll find a use for the 75-ohm twin lead that comes with the Surplus Dipole fixture, instead of using the RG-174 coax.

So let your imagination guide you, and you can probably come up with a some sort of other ideas for use of fly fishing reels for an antenna that will fill your portable requirements.

Fair Radio Sales in Lima, Ohio. Dipole fixture Fair Cat. # DP-MK-911; Terminal panel Fair Cat # TP-10 (has 10 each Heavy duty push terminals); CRT-3 Gibson Girl wire, Fair says they have few left, but tangled wire.; Martin Model 61 reels were obtained from Wal-Mart, but are also available from sources on the internet.; Brass machine screws, finishing washers, and thumb nuts can be used in place of the surplus push connectors to clamp the antenna wire and can be found at your local hardware store.; Radio Works has the .070 black Kevlar 500 lb test rope.; Digi-key has pre made non insulated ferrules. The P/N's used in this project are: For # 20 wire as marker 288-1085-ND; For # 20 wire looped upon itself ferrule used as retainer 288-1090-ND; For # 14 Flex weave as marker 288-1105-ND; For # 14 wire looped upon itself ferrule used as retainer 288-1110-ND

Member Comments:
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HF Reel type portable antenna for qrp  
by WB9IPA on April 5, 2004 Mail this to a friend!
Great idea! This should be very useful for the ham campers or others into operating outdoors.
 
RE: HF Reel type portable antenna for qrp  
by K0BG on April 9, 2004 Mail this to a friend!
A new twist to an old saw as they say. Good Job!

Alan, KBG
 
RE: HF Reel type portable antenna for qrp  
by LNXAUTHOR on April 9, 2004 Mail this to a friend!
- great antenna and great ideas! i use an SD-20 crappie pole and two RS SWL reel antennas for a portable dipole - works FB!

- while many folks concentrate on and seem more interested in portable center-loaded verticals, the antenna described here will work far better... i guess convenience is the factor in the interest in more portable antennas (e.g., miracle whip-type antennas)...

- other antennas i have used w/great success included hamstick dipoles (with a Lakeview dipole mount)...

- but given the choice, time, and opportunity of location, i'd choose the antenna described by the author here every time!

- thanks for the pics and text - nice job!
 
HF Reel Type Portable Antenna for QRP  
by WA8MEA on April 9, 2004 Mail this to a friend!
Rather complicated and bulky. I might add that I've been making very simple versions of "reel" antennas for many years that are much more portable, and can fit in a sandwich bag.

73, Bill - WA8MEA
http://qth.com/dwm
 
RE: HF Reel type portable antenna for qrp  
by KB1KIX on April 9, 2004 Mail this to a friend!
I do the camping thing a lot. I'm gonna rip one of these for both for amateur use as well as shortwave!

I can get sued for using this statement now, though I've used it for years..... butI have nothin' to lose...

"I'm lovin' it!"

Lots of great ideas I've used here for club projects.

I'm even thinkin' ARES on this one.

Jonathan
 
RE: HF Reel type portable antenna for qrp  
by KC8VWM on April 9, 2004 Mail this to a friend!

Great idea! I have toyed with the Sangean reel up SW antenna in the past. Your design would probably work 10X better.

For those interested, last week while I was shopping at Home Depot with my wife for her usual lawn and garden projects, I suddenly veered off into the bulk electrical wire isle of the store to look for some solid #6 ground wire for a new antenna project.

While I was there, I saw them selling 18 ga. stranded bare copper wire on a 500 ft. reel for under 20 bucks. My first impression was that it was definitely suitable as "HF grade" wire. I think I will pick up a reel this weekend and build this antenna. (That is, if my wife doesn't make me dig too many gardens or fish ponds.)

Excellent portable antenna idea! Thanks.

73

Charles - KC8VWM
 
HF Reel Type Portable Antenna for QRP  
by N8BOA on April 9, 2004 Mail this to a friend!
Great job
Here is a idea, Keep your feed line short by making it a V insted of a inverted V Less feedline loss and if your suports are far apart you can change band easy since the works are at ground level Also the high voltage part of the antenna is free and clear.
Just a idea
Sean
N8BOA
 
RE: HF Reel Type Portable Antenna for QRP  
by K3AN on April 9, 2004 Mail this to a friend!
But the high current part (that does most of the radiating) is near the ground. Not good!
 
RE: HF Reel Type Portable Antenna for QRP  
by N8BOA on April 9, 2004 Mail this to a friend!
K3AN Chat
What about a vertical mounted on the ground same thing ?? High Current near ground I alwas thought it was the center of each side where you have both votage and current or P=I*R
Sean
N8BOA
 
RE: HF Reel Type Portable Antenna for QRP  
by K9GDV on April 9, 2004 Mail this to a friend!
Hello Sean, Like the idea of using as reversed inverted "V" will try that and see how antenna performs, Also be easier to change bands. May try rigging it up using 450 ohm ladder line and 4:1 balun and see if might work similar to G5RV type multiband antenna. The dipole fixture as it come from Fair Radio does have about 25 ft of 72 ohm twinlead on the prc-74 antenna fixture, as it was used with the prc-74. Maybe easier to use the 72 ohm twinlead instead of the RG-174???
 
RE: HF Reel Type Portable Antenna for QRP  
by KQ6XA on April 9, 2004 Mail this to a friend!
Nice antenna, article, and photos!
You might enjoy the HFpack group.
http://www.hfpack.com

73---Bonnie KQ6XA
 
RE: HF Reel Type Portable Antenna for QRP  
by K2WH on April 9, 2004 Mail this to a friend!
They aren't Dudes!

Oops! Sorry, wrong thread.

K2WH
 
RE: HF Reel Type Portable Antenna for QRP  
by K4JSR on April 10, 2004 Mail this to a friend!
Bill,
His next project is an inverted U 80 Meter
DUDEpole! (Not to be confused with fan DUDEpoles)

73, Cal K4JSR
 
Check this out too ...  
by K1HC on April 10, 2004 Mail this to a friend!

I don't want to take anything away from the author's efforts; it was certainly a good article - good explanations and pictures, but for the same idea with a much simpler and perhaps even less expensive approach see April 2004 edition of World Radio, page 52 - the DWM Communications yo-yo antennas advertisement. I haven't bought one yet, but it's on my list of things to buy. Perhaps they'll be selling at Hamvention ... only a month away!

73,

Dick, K1HC
 
RE: HF Reel Type Portable Antenna for QRP  
by K7LA on April 10, 2004 Mail this to a friend!
"Rather complicated and bulky. I might add that I've been making very simple versions of "reel" antennas for many years that are much more portable, and can fit in a sandwich bag.
Bill - WA8MEA"
---
That may be true Bill, and while you build a good product, kindly note that this contributor is not in the commercial antenna business like you are.
It's a PROJECT, and we should all THANK the contributor for his efforts in advancing the hobby.


 
HF Reel Type Portable Antenna for QRP  
by KA4RKT on April 11, 2004 Mail this to a friend!
Very neat antenna idea. I used to use a similar deal with two AT-984/G reels many years ago. I also have Collins tape reel that I have used now and again - I like it because you simply unreel the tapes per the chart on the side, nice and lazy to use. :-)

Fly reels and GRA-4 reels make for easy handling of the antenna wire, less chance for tangling when erecting the antenna. GRA-4 mast kits are easy to put up for supporting the thing, too.

Another idea I have used at QRP levels is a pair of the cheapie Sangean or Radio Shack reel antennas that were originally intended for shortwave receivers. (I also have one of the PRC-70 portable dipoles, but it is not as neat since it has no reels) Works well with my 703 and a tuner. I saw the idea on another of the ham forum sites exactly like what I have used. I was surprized today when I ran across this URL - http://www.qth.com/dwm/ - which has a small reel system similar to my cheapo setup. Look at the "Yo Yo Vee" in the menu.
Interesting.

73

Tom KA4RKT
 
RE: Check this out too ...  
by K9GDV on April 11, 2004 Mail this to a friend!
Hello Dick, k1hc Anyway if you want to build yourself a Yo-Yo antenna might want to check out Walmart Sporting goods section and look for Camping Clothes line reels (or spools) They look just like DWM's Yo-Yo anyway. Buy them for about $1.48 each. The 2 halves unscrew and you remove the rope and replace it with about 35 to 40 feet of insulated wire (306 ft spool avaiable from Fair Radio Cat #SEB-400X3 at $12.95) and you have yourself a Yo-Yo antenna. (With 306 ft of wire you can make a whole lot of Yo-Yo antennas.) Just add Pl-259 connector if desired or hook up wire to your tuner throw spool in tree and you have the Yo-Yo antenna. I wasn't going to mention the Yo-Yo but since subject was brought up figured I tell how I made mine.
 
HF Reel Type Portable Antenna for QRP  
by KX4TT on April 12, 2004 Mail this to a friend!
I have a Yo-Yo Dipole made up of two of the aforementioned clothesline reels from Wal-Mart, and I have a third reel set up to act as a counterpoise ground for my vertical antennas, as per the HF-Pack Group guidelines. I use heat-shrink tubing to mark the resonant spots for each band - and it works FB!!

Lee N4MVL
 
HF Reel Type Portable Antenna for QRP  
by KC4AUF on April 12, 2004 Mail this to a friend!
Hi Marvin, I loved your artical it shows real amateur radio inovations. Being a military surplus nut I happen to have the items needed to make such an antenna. There seems to be a lot of talk about a yo-yo antenna but your antenna looks like it's just waiting for the chance to go on a DXpedition even if it is only to the nearest park,hi hi. There is another factor about your design that would be hard to duplicate with a yo-yo antenna "It just looks cool" That you can't buy, thanks for your time, effort and hard work that went towards making this a more fun hobby for all of us.
73,see you on the bands
KC4AUF Tony Day
 
HF Reel Type Portable Antenna for QRP  
by VE3FFK on April 13, 2004 Mail this to a friend!
Just one little tip.. I suggest you mark the ferrules
with either an engraver or metal stamp, rather than
paint or a marker. Even in temporary use, they rub
off, and you have to count the ferrules as they go
out to find what band you have deployed.
73 mike k- VE3FFK
 
HF Reel Type Portable Antenna for QRP  
by KE4ZHN on April 13, 2004 Mail this to a friend!
Great way to go portable qrp. Nice work.
 
RE: HF Reel Type Portable Antenna for QRP  
by K9GDV on April 13, 2004 Mail this to a friend!
VE3FFK just answered idea of how to mark the resonant point on antenna for me. I don't have a heat shrink wire marker, but I do have the engraver, so will try that method of permanently marking ferrule with frequency. My original idea was to go ahead and use ferrule then place a marked piece of heat shrink over it as frequency marker, as ferrule would keep heat shrink from slipping any, but engraved freq on marker is probably better idea.
TNX es 73's
 
RE: HF Reel Type Portable Antenna for QRP  
by WB2WIK on April 14, 2004 Mail this to a friend!
Reely nice.

<I can't believe I said that.>

Good job!

WB2WIK/6
 
RE: HF Reel Type Portable Antenna for QRP  
by SWLLISNER on April 14, 2004 Mail this to a friend!
Making them for years?...well, thanks for sharing your plans, Bill. I like the can-do attitude of this author, not your egocentric rambling.
 
RE: HF Reel Type Portable Antenna for QRP  
by WA8MEA on April 14, 2004 Mail this to a friend!
I guess the title threw me for a loop. "Portable" in the title didn't seem to relate to my first impression of the pics. But realizing that Marv is a little older than yours truly, I reasoned that he just might be from the "old school" of portability. While I grew up in the generation of miniaturization, Marv grew up with the Woodstock generation of back-packers. I like to carry my antenna & rig in a lunch box. Marv probably likes to throw his gear over his shoulders.

"QRP" in the title didn't seem to fit, either. If anything, this antenna is WAY COOL for QRO portable operation! Some of us "porties" have been kicking around the idea of taking our amps with us on our next camping trips. And although my version isn't just for QRP, and works great with the 100 to 200 watt rigs on the market, I don't know if I'd ever trust feeding the legal limit into #22 wire----no matter how high quality the wire is. (And if you do make your own version of any porty-antenna, PLEASE don't skimp on the wire if you're going above QRP levels.)

Marv's thicker wire also allows for broader coverage of each band of operation. In other words, Marv's antenna covers a lot more frequency turf at lower SWR.

My apologies, Marv. I over-reacted to the title, and I guess I should have commented on "the meat" of your article. But we all seem to be "headline readers" in this information age.

But then again, this is E-ham. And maybe I just wanted to try and fit in by complaining and whining a little. ;-)

73, Bill - WA8MEA
 
HF Reel Type Portable Antenna for QRP  
by K6RXL on April 19, 2004 Mail this to a friend!
Great idea, but somewhat bulky if a backpacker. Nothing beats an end fed half wave vertical antenna (EFHWVA) for simplicity! Only one support necessary, no bulky feedline to carry and performance equal to a half wave dipole, depending upon configuration and setup.

'73

Kevin
K6RXL
 
RE: Check this out too ...  
by N0EW on April 20, 2004 Mail this to a friend!
One can also go to Wal-Mart, K-Mart, etc., and purchase a camping clothesline reel for $3 or $4. This will provide you the plastic "reel" enclosure. Next obtain some thin wire (I like "Silky" wire (#26 copper clad steel) sold by www.thewireman.com and others) and wrap your own portable dipole to your desired length. One of our local ARES members has done this and reports it works nicely.
 
HF Reel Type Portable Antenna for QRP  
by N0EW on April 20, 2004 Mail this to a friend!
Another idea: Purchase two (metal) tape measures from a hardware store that are long enough to reach your lowest band. Use a hose clamp and plastic dog-bone insulator to hand-tighten your feedline wires to the desired point along your tape measure dipole. With 100 watts I worked ex2z in Kyrgyzstan (on the west boarder of China) with a dipole like this (dipole height was a little less than 20 feet, perhaps 17 or 18 feet).

These are fairly portable but obtaining great feedpoint heights can be a challenge. Many tape measures do have belt clips to assist in mounting them temporarily to something (perhaps a rope tossed over a tree branch). As a bonus you can even use your antenna to measure things, the first of which is the required length for your dipole (hi hi).

Here is a picture:
http://www.n0ew.radiomonkey.org/images/Tape_Measure_Hookup_04.jpg
 
HF Reel Type Portable Antenna for QRP  
by KA1HSP on September 26, 2004 Mail this to a friend!
Hello,

I am trying to find an item I used in the National Guard where I served 10 years as a radio operator. I am hoping to add RL122/GRA4 antenna reel to my amateur radio inventory for portable/emergency operations. The RL122/GRA4 antenna reel is part of the AS244/GRA4 and also the MX1137/GRA12 antenna kits. I have ongoing "auto searches" on ebay and also www.govliquidation.com and also have been contacting defense contractors cross referenced through www.iso-parts.com

NSN 5985-00-497-8765 RL122/GRA4 Antenna Reel
NSN 5985-00-244-5147 or 5985-00-264-7506 AS244/GRA4 Antenna Kit
NSN 5999-00-378-4718 MX1137/GRA12 Antenna Kit

Any assistance is appreciated. 73's .....
Joe
KA1HSP
Monson, MA

 
RE: HF Reel Type Portable Antenna for QRP  
by WA8MEA on November 8, 2005 Mail this to a friend!
You know, to this day I have NEVER understood why QRP was used in this title. The wire on this thing is so thick, it outta handle a KW or two with ease.......

73, Bill - WA8MEA
http://HamRadioFun.com
 
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