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Author Topic: Field Day Antennas for QRP SSB  (Read 7059 times)
WB6BYU
Member

Posts: 16653




Ignore
« Reply #30 on: May 25, 2017, 02:33:40 PM »

THE ANTENNA GEEK'S TOOLBOX FOR FIELD DAY

No, I don't expect you to haul all this stuff along:  I'm often supplying most of the antennas for a 4A operation,
with enough spares to equip a second one "just in case".  (Some might say that I've extended the "belt and
suspenders" approach to include duct tape, rope, and glue.)  But maybe it will give you some ideas of things that
make things easier for you to set up your antennas.


WIRE MEASURING BOARD
This is a 3' scrap of 1x2 with a couple nails driven into it 2.5' apart, and the space between the nails calibrated
at 6" intervals.  I added a small nail beside one of the big ones:  I can tuck the end of the wire there and wrap
the wire around the nails, counting as I go.  Each full wrap up and back is 5', and I can measure a 67' wire
quickly to within a few inches.  (This assumes your wire isn't to stiff, of course.)  I have a longer 5' board that
I use at home, and first used this technique with a pair of nails across the inside of my Dad's garage door.

I think this one innovation has made a huge impact on my ability to put up wire antennas (and to improvise them
on the spur of the moment.)  Suddenly I don't need that 100' tape measure for an 80m dipole:  I can measure it
myself in less than a minute.   Among other things, it means that most of the pieces of wire from prior antenna
experiments in my junkbox are marked with the length on a piece of tape.  All the "usual suspects" are
already at hand (often from years ago), or I can choose one closest to the length I need.

THROWING BUCKETS
A bucket or plastic dishpan containing >100' of throwing rope (smooth braided line of some sort) and a weighted
tennis ball (4 - 6 ounces of fishing weights).  The choice of line is important, as I want to minimize the friction
as it runs over a branch.  This line never gets used for anything else - I use it to pull another rope over the branch
that actually ties to the antenna, so the throwing rope always stays available for the next antenna.  With one of
these I can get an antenna up 50' - 60' in a tree.

OTHER ANTENNA LAUNCHING METHODS
Slingshot, fishing rod, dog ball slingshot, dog ball throwers, etc.  Maybe a compressed air launcher at some point.

CENTER INSULATORS
I have several antenna feedpoint insulators with coax attached that I cut from some outdoor PVC lattice material.
They are "T" shaped, with a hole in the end of each arm for tying the antenna wires, a couple holes and a tie wrap
for strain relief on the RG-58 coax, and stainless steel bolts and wing nuts connected to the ends of the coax for
electrical connection to the antenna wires.  These make it easy to string up most sorts of wire antennas without
soldering.  And I usually have a couple of Budwig insulators and some other assorted types as spares.

ANTENNA END INSULATORS
I don't use them.  With 50' of plastic baling twine tied to the end of a wire, how much difference is an extra 4"
plastic insulator going to make?  Though, I'm sure if you looked though one of my boxes you'd find a few...

WIRE
A few spools of stranded, insulated hookup wire, plus a box of pre-cut lengths (including dipoles for most
bands, a full wave loop for 80m, various quad loops for 40m, etc.)  Most of it is #18 to #24 or so.  It is
light and flexible, but strong enough for a 160m dipole.  (I don't pull up a lot of strain on my antennas.)
I tie knots in it to attach it to insulators, other wires, etc., and it is flexible enough to measure with the
measuring board.

FEEDLINE
A big tub.  I've been collecting stray coax at hamfests over the years, so there are some lengths of RG-8, RG-214,
RG-58, RG-6, RG-11, RG-14, RG-8X, etc.  Some 100' pieces, some 50', and assorted others.  Mostly PL-259 or
BNC connectors (though I rarely use the latter).  A few have bare ends for when I'm improvising an antenna.
And stray coils of ladder line / twinlead of various sorts.  For most antennas we use thinner coax like RG-58 or
RG-8X to get down to ground level, then run the bigger stuff along the ground to the transmitter.

ROPE
A couple spools of baling twine, and a big tub of pre-cut pieces marked with lengths.  We used to live on a farm,
so I had lots available:  the twine used for pulling electrical wires or bundling Christmas trees will also work.
The tub has mostly 50' and 100' pieces, though I'm finding that 60' is more convenient than 50' in many cases.
We use 50' - 100' on the end of each antenna wire, plus some for hoisting the feedpoint, so a dipole at 50' may
use 300' of rope.  Then I usually have a tub of other types, too.

I used to use Mason's Twine (or even dental floss) for my antennas, but now my eyesight isn't as good for
untying knots and I find I like larger ropes when the weight and bulk isn't a limiting factor.

WEBBING / STRAPS / ANCHORS / ETC
One of the Field Day sites we used to use was paved, and we weren't allowed to drive any stakes in it to anchor
our masts, etc.  But it had some large rocks around it, so I cut some lengths of webbing that would fit around them
to which we could tie off our guy ropes.  Various straps are also handy to protect tree bark, or generally to run from
an anchor to a point where it is easier to adjust a guy rope.  I have brass rings on the webbing to tie to, but
carabiners would be convenient, too.  Meanwhile, old railroad spikes make good anchors in a lawn, as they can be
driven down low enough not to endanger a mower, but still be pulled out.  Other sorts of stakes work, too.

MAST SECTIONS.
Typically 100'+ of the older 4' thick-wall aluminum military camo mast sections.  And often a bag of the fiberglass
ones as well.  The metal ones get used to put up the TA-33jr and the yagis for 15m and 10m if we use them.  The
fiberglass are used for wire antennas, or sometimes VHF, but mostly we use trees instead.

OTHER ANTENNAS
I take a TA-33jr for the SSB station, because they usually need all the help they can get.  I have homebrew 2-el
yagi for 15m and 3 elements for 10m that I also take along, but they haven't had much use the last few years.
Then there is at least one tub of old wire antennas:  the 185' vee beam, a wide-band 80m dipole, J-pole for 15m,
a 40m dipole I inherited somewhere, etc.

ANTENNA SPREADERS
Some antennas, such as a 2-element wire quad or yagi, need a top spreader when mounted on a mast.  Typically
I want a something around 10 - 16' long.  A pair of 8' 1x2s with a couple bolts through the overlap, or 3 sections of
telescoping aluminum tubing is wide enough for a 40m quad and still folds up small enough to fit in my van.

ANTENNA TUNERS
I try to provide matched antennas for the other stations, but 80m still may need a tuner to cover the whole
band.  I have a Johnson Matchbox for my CW doublet, though last year I ended up with a length of ladder line
that it wouldn't match very well (it actually has a somewhat limited matching range.)  The MFJ-949 and similar
tuners usually are adequate.  This year I'm building an external balun to use with an "L" network tuner on my
doublet.  Or maybe a high power version of the Ten-Tec AC-1...    Anyway, its good to have some available.

ADAPTORS
Never hurts to have a few BNC/PL-259 adaptors on hand, and I end up using a lot of barrel connectors to splice
coax lengths together.  (I used to use some 8" wall pass-throughs for that purpose, as I had a handful of them.)

SARAN WRAP
Or equivalent.  For temporary waterproofing of coax or electrical connections.

PLASTIC BAG CLOSURES
Our local Health Food Store has some nice bag closures with room to write the SKN.  These are great to clip around
the feedline and mark with which antenna it goes to.

OTHER TEST EQUIPMENT
Dummy load, SWR meter, antenna analyzer, dip meter, VOM

KNOWLEDGE OF KNOTS
Knots are second nature to me, having started tying them in Scouts and continued ever since (especially
for putting up antennas.)  At a minimum you should be able to tie a loop in the end of a rope, tie two ropes
(or wires) together, and tie a rope off to an object.  The exact knots you use don't really matter, but you
want to use something that is easy to untie when it is time to go home.  My favorite loops are the
bowline, figure-8 followthrough, and overhand followthrough, though the latter may be harder to untie.
(I often leave a loop in one end of my ropes and/or wires.)  For tying ropes together I use some variant
of the sheet bend (including a slippery one that untie with a pull of the free end).  A tautline hitch makes
it easy to adjust the tension on a guy or antenna rope.  There are numerous animated instruction videos
available on line, and many other knots you can use instead.  But these are simple and easy.

ETC...
Spare hose clamps and machine screws for yagi elements
Tape for securing coax to mast and sundry repairs
List of antenna dimensions, especially for wire yagis / quads where you can't just adjust for minimum SWR.
Antenna books (in case you can't think of something for a particular situation.)
Survey flagging to mark guy ropes and other potential hazards.
Toolbox, including spare coax connectors, crimper, etc.
To assemble the yagis, I have color-coded the wrenches and nuts with colored tape
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WD4ELG
Member

Posts: 108




Ignore
« Reply #31 on: May 25, 2017, 10:12:15 PM »

Awesome FD memories.

I have always wanted to try a Bruce array for DX.  Makes sense that it is very low angle of radiation, no help for FD QSO's!
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KC4ZGP
Member

Posts: 725




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« Reply #32 on: May 26, 2017, 05:59:18 AM »

Herr BYU,

My 17 and 20 meter delta loops spit RF all the way to California, Canada and South America.
They have not failed me yet.

Now this 160 meter loop. Oh GAWD! it works so wonderfully well. According to a chap in
Western Virginia, I'm coming in just above the noise. I cannot wait till the low band opens.
I'll be the Voice of Georgia.

73

Kraus


« Last Edit: May 26, 2017, 06:01:30 AM by KC4ZGP » Logged
WB6BYU
Member

Posts: 16653




Ignore
« Reply #33 on: June 06, 2017, 11:12:30 PM »

We're getting short on preparation time, so we better start wrapping things up (at least for
this year.)

This episode is on directional antennas.  It will be of particular interest to those on the fringes
of the continent, or those who want good coverage into a particular area.  These tend to be
mono-band antennas. so more suited for a multi-operator group than a single 1B operator
with a single multi-band antenna.


First, of course, we need to consider directivity in both elevation and azimuth.  Directivity
implies that your signal is focused more in one (or more) directions at the expense of
other directions.
  That's why you need to look at what beamwidth you need for your
specific location and desired coverage.  From here in Oregon, a 50 degree beamwidth covers
most stations over 1200 miles away, except for Alaska and the Pacific (which we probably
will work anyway.)  A 40 degree beamwidth starts to chop off parts of Canada and southern
Texas and Florida (though signals in those directions may still stronger than a dipole.)
From Maine or Florida or Calgary you may want a wider beamwidth at higher elevation
angles to get closer stations.

One example of why this is important:  my 40m doublet used on 20m has a half power
beamwidth of 54 degrees, which works out pretty well.  If I extended it to 2 x 5/8 wave
I get about 1.5 dB more gain on 20m, but the beamwidth narrows to 35 degrees.  Is it
worth it?  I'd have to look more closely at my plots of active stations vs. azimuth angle,
but my guess is that I'll work more stations with the wider angle and lower gain.

And that gives us some limits to work with:  making a colinear antenna longer than about
1 wavelength (that is, "two half waves in phase") is generally not a practical solution
for most CONUS stations, at least when the desire is to cover most of the available stations
with a single antenna.  (It makes much more sense if you are relatively far from the East
Coast.)   So antennas that rely on width to provide gain (such as a Sterba Curtain) are not
going to be a good choice.

Broadside gain (stacking elements vertically) maintains the wide beamwidth, but requires
significant height to achieve much improvement.  A 2-element broadside array for 20m with
elements at 50' and 25' is only marginally better than a single element at 50':  I'd consider
that the minimum height to use such an antenna.  Even among the tall Douglas Firs here
in Oregon, 50 - 60' is about the highest we normally get an antenna up.  (That may change
if we go to a pneumatic antenna launcher, though the logistics get more complicated with
height.)  And this can be carried too far to get too narrow of a vertical beamwidth, as happened
with the 15m folded Bruce array off the fire tower.

The most practical approach to achieve directivity and gain seems to be end-fire arrays, typically
yagis or quads in some form or another.  These narrow the beamwidth in both elevation and
azimuth, but are capable of good gain before the pattern get too narrow.

Commercial yagis can be used, of course.  In my case we tie a rope the back of the boom for
an "Armstrong Rotator", point it East, and leave it there.  For light weight operation, a 2-element
beam is a good compromise of gain vs. complexity, and these can be built quite light using
aluminum tubing if they aren't intended to survive winter storms.

But from the perspective of cost, weight and size, it is hard to beat wire beams.  A 15' spreader
is sufficient for 2-elements on 40m, and 10 - 12' is good for 20m.  These can be mounted on
top of a tower or mast, or hoisted into a tree using a rope, then the elements tied off with
ropes to aim it in the desired direction.  Like this:



(I'd get the ends of the 40m elements higher off the ground for better efficiency, however.)
A pair of 8' 1x2s bolted together with a 1' overlap makes a convenient spreader, or telescoping
aluminum tubing.

DK7ZB's wire multi-band beam is another option that could be
installed this way.

What about a quad?  The limiting factor is often the available height above ground:  until you can
the antenna up about half a wavelength, a yagi will probably work better than a quad or delta loop
hanging from the same boom because the average height of the antenna is greater.  (However, if
you are trying to improve signals over a shorter path on 40m, or have some ground slope to work
with so the effective height of the antenna is greater, the quad may be a better option.)

For longer antennas, using a rope boom strung between two trees with the wires hanging from it
seems the best approach that I've found.  Aluminum electric fence wire (#17 1/2 gauge, or
whatever the smallest size is) would be my choice for light weight:  I normally use thin stranded,
insulated wire, but the insulation becomes an issue when trying to optimize element lengths.  The
solid wire does need to be handled more carefully to prevent it from kinking, however.

The simplest approach is to tie the center of each wire to the rope at the proper location, with a
long line on each end, then pull the boom rope up into position and tie off the ends of the elements
as inverted vees.  Don't underestimate how much rope this takes!  But you don't need to use much
tension (or the whole antenna will sag) so a spool of Mason's twine or kite string should work.  Try
to get the element ends out as far from the center as possible (flatter angle).  Note that the
inverted vee elements will require some readjustment of element lengths.

With more height a delta-loop quad becomes practical, and can use the same basic construction.
Like this:



(Thought I wouldn't recommend those dimensions.)

Most of the standard yagi and quad designs can be adapted to this format, though they may
require some re-optimization.  I've adapted such yagis from the W4RNL OWA designs, as well
as those of DK7ZB and DL6WU.  For quads I've worked from W4RNL and G0KSC designs.

For the 20m yagis, 5 or 6 (OWA) elements on a ~50' boom seems like a good size.  For the quads,
a 5-element G0KSC derivitive on a 60' boom is about the upper limit, and 4 elements on a 35'
boom may be a reasonable compromise.  The G0KSC designs have a wide operating bandwidth,
with SWR below 1.5 : 1 from 14.1 to 14.35 MHz for a phone station.  Even 2 or 3 elements gives
useful gain for a QRP station.  While a 2-element quad will usually work best when fed with 112
or 200 ohms, the longer beams often will have a direct 50 or 75 ohm feed impedance.  Same
with the OWA yagis when they are adjusted for inverted vee elements.

For 40m, 2-3 elements seems like a reasonable size.  I've used 3-element delta loops on 40m
before, but they were at too low of a height to really be effective:  a yagi would have worked
better when the supports are only about a quarter wavelength high.


Note that with the higher gain antennas you may need an accurate compass to aim them in the
right direction, including correcting for magnetic declination.  If you don't have two trees aimed
in the right direction, you can use two ropes on one end over different trees and adjust the
angle of the antenna anywhere in that range.  That can even allow you to rotate the antenna
over a span of 60 degrees or more, though the element end lines will have to be moved when
you do so.


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WB6BYU
Member

Posts: 16653




Ignore
« Reply #34 on: June 08, 2017, 10:04:07 PM »

A few more tips to help make setting up wire antennas easier.  Some of these can mean
a big difference in how long it takes to set up your antennas, and the ratio of time spent
setting up vs. time spent operating, especially when you only have a short time available
(like a SOTA activation when you have to hike some distance.)

Making it fun and easy is the key!


1) Wind all your ropes and wires in a figure-of-8 across your palm between thumb and
little finger, or between your hand and your elbow.  I often spend a whole evening after
Field Day rewinding ropes that someone else wound up, and those who have been out to
Field Day with me before know how picky I am about this.

Why?  Because that avoids putting a twist in the rope and keeps it from tangling when you
go to unwind it.  (I've gotten sunburned sitting there trying untangle ropes - it is much more
fun to be operating the radio instead.)  My favorite demonstration is to take a 60' piece of
baling twine, wind it up quickly while I'm talking, stick it in my pocket, then pull it all the way
out from one end without tangling

For this to work, every layer has to cross over in the center - you can't just wind it around and
around something (that adds a twist).  But that also establishes an order to the winding -
the crossings in the middle of your palm are in order, and it is less likely that one turn will
slip or catch on another while the rope is unwinding (that's what causes a lot of tangles.)
If you've ever had to wind a flat ribbon (or teletype tape), such twists are immediately
obvious.  So I can climb to the top of a 100' tower, pull out a chunk of rope that has been wrapped
up in a box for a few years, grab one end and toss the rest off the tower, and not expect to
have any tangles.  Sure, not everyone can wind it as fast as I do - I've had 45 years of practice -
but it doesn't take that long to learn.  I use it for just about everything, from ropes to wires to
extension cords to garden hoses.  (Well, some things are too big to do across my palm...)

2) Have a convenient way to keep your ropes and wires bundled.  I've used rubber bands, but
those decay over time and make a mess.  Now my favorite for this purpose are pipe cleaners:
they come in multiple colors and are long enough to tie most bundles of rope or antenna wire.

Actually, much of my wire and rope is tied with itself, as this means I don't need to worry about
dropping a tie when out in the field.  After winding in a figure-8 I leave some extra on the end,
wrap it a few times around the middle to hold the turns in place.  Then I make a bight in the
rope/wire that I pass through the hole at one end of the bundle (such as where my thumb was),
and pull the loop over the top of the wound rope.  Then I can pull the free end to tighten it
up.

This has the added advantage that I can tie the end of the rope / wire to something before I
loosen the bundle
.


Here's how it works in practice:  I toss a rope over a branch (using a throwing bucket) and use
that line to pull over a piece of baling twine to serve as a halyard.  On the end of that I tie one
of the dipole center insulators with 50' of RG-58.  At this point the center insulator is hanging
about 4' off the ground.  Then I grab the wire bundles I want to add to it and tie them on the
ends of the insulators:  the wires tie to the insulator for strain relief, then the end of the wire
goes to the bolt and wingnut to make the electrical connection.  A typical Field Day installation
may have 3 bands on the dipole, so there are 6 bundles of wire (hopefully color-coded) hanging
from the insulator.  I take each bundle in turn, unwrap the bindings on it, and string it out along
the ground below where I want it to end up.  The further apart the wires are, the less tuning
interaction.  I also make sure I have a length of rope on the end of each wire - typically 50' or so.

At that point I can pull on the halyard to raise the feedpoint, making sure the wires don't tangle.
If I didn't put a rope on the end of a wire and it gets off the ground, I'd better add one now.
Once it is at full height I pull out each element in turn and tie it off to a bush or whatever is
convenient.  (In a congested area, it's better to tie it off to a tree about 8' off the ground so
folks don't get tangled in the ropes.)  If I want the elements higher, I may use the throwing
bucket to pull the end ropes over high branches


Of course, that's not to say that there aren't other ways to do it, but this is what has worked
for me when setting up antennas by myself.    Do you have other methods you can share that
work for you?


3)  I haven't found any good reason for putting the ends of your antenna wires close to the
ground, unless you are worried about your signal being too strong.  I figure the antenna ends
should be at least half (or more) the height of the center when hung as an inverted vee to
maintain good efficiency:  one way to accomplish this is to make your end ropes at least as
long a the antenna wire.

4)  If you are using ladder line, run it all the way to a tuner by the rig, rather than using a balun
and a length of coax, unless you have already calculated the losses in the coax and are willing
to live with them.  It's not uncommon to see 6 - 10 dB of loss, even in a 20' piece of good coax,
if you happen to get the wrong combination of feedline lengths on a doublet.  Just because you
can match it with your tuner doesn't mean it is efficient, and these are the sorts of losses that
can make a significant difference when trying to run QRP SSB.

5)  Make sure you have a comfortable chair.  I can't sit on a picnic table bench for very long before
my butt gets sore, and a rock is even worse.  (Ant nests aren't fun, either.)  Many folks use the
common nylon-and-metal-rod folding chairs, but I find that they are too slouchy and I can't sit up
to the table when using CW.  I have an old straight-back chair with a padded seat that comes out
with me each year, and other folks get envious as it gets later into the afternoon and evening.

6) For CW, I tape a pen to my middle finger.  Yes, it can look like a rude gesture, but that allows me
to operate the paddles with my thumb and forefinger, then write almost normally with the pen to
log or take notes, without trying to find where it rolled off down the table...


7)  Remember that these are intended as tips to make setup and operation easier - they are not
the only way to do it.  Feel free to adapt as suits your specific circumstances, and ignore any
that don't sound like they will be useful.


8 )  Practice makes perfect, or at least better.  Some of these (like winding the rope) do require
practice to get the hang of it.  Practice in your back yard or a local park (regulations permitting).
Makes a great excuse to go out for an afternoon of operating while you test out your antennas...


9)  Have a backup plan, in case your antenna breaks, or that tree you used last year came down
in a storm.  (But, no, you don't have to carry as much stuff as I do.)


10) Learn from what worked, and especially from what didn't work..  Even if you operated
all by yourself, make a list of what worked well, what didn't, and what you want to try differently
next time.  (It only took one backpacking trip using magnet wire dipoles with speaker wire for
feedline before I switched to stranded insulated wire and RG-174.)


11)  Experiment.  If you have the time and space, put up two different antennas and switch
between them to see which is better in your specific situation on different bands, distances,
times of day, etc.  Don't assume that what works for someone else is the best solution for you.


12)  Have fun.  That's the most important thing.  We all go out for Field Day (and other
portable operations) with different priorities and values, and enjoy different aspects of the
events.  Be honest with yourself about what you enjoy the most, and tailor your operation
to give you the most return for your effort.  You don't have to do it any particular way
(though you should follow the event rules if you are going to submit an entry.)  And, when
things go wrong, think of all the good stories you'll be able to tell afterwards.
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WB6BYU
Member

Posts: 16653




Ignore
« Reply #35 on: July 02, 2017, 07:19:34 PM »

So, how did Field Day go for you?  What worked well?  What didn't?  What would you do
differently next time?


We made a few changes this year.  The GOTA 40m antenna and the SSB 75m dipole were
reoriented to aim up and down the West Coast (since that was where most of the contacts
were) rather than to the East.  The GOTA and SSB dipoles were replaced with delta loops
with the point down, dimensioned for a 200 ohm feedpoint impedance:  the GOTA loop
used a 4 : 1 balun, while the SSB loop used a quarter wave matching section of zip cord.

We also put the triband yagi up to 36' on the sectional aluminum poles, but after looking
at the bowing in the mast I think that 32' would be a better choice.

The digital station used a full wave 80m horizontal loop in a triangle, rather lower and
on the back side of the hill, but adequate (though it picked up a lot of RF from the other
stations.)

Perhaps the biggest change was that I gave a class for some of the operators beforehand
and emphasized watching the ALC meter to know that you are modulating the rig to full
output power.  Even some of the "more experienced" HF operators in the club didn't know
about that minor point.

I haven't seen the log sheets yet, but I think the voice stations made significantly more
contacts this year than before.  Some operators commented that they didn't have nearly
as much of a problem being heard compared to last year.

My most important learning was about my new throwing bucket:  rather than the thin braided
rope I used in the others, this had braided deep-sea fishing line with a short section of paracord
to hang onto while throwing it.  WOW!  The first try went over the next branch higher than I was
aiming, and came down through the branches without requiring any of the jerking or wiggling
on the rope that I normally do.  It probably added 10' to my accessible height:  too bad it wasn't
until the last antenna that I tried it, after someone borrowed my usual throwing bucket.
Logged
KM3K
Member

Posts: 390




Ignore
« Reply #36 on: July 14, 2017, 02:27:48 PM »

My most important learning was about my new throwing bucket:  rather than the thin braided
rope I used in the others, this had braided deep-sea fishing line with a short section of paracord
to hang onto while throwing it.  WOW!  The first try went over the next branch higher than I was
aiming, and came down through the branches without requiring any of the jerking or wiggling
on the rope that I normally do.  It probably added 10' to my accessible height:  too bad it wasn't
until the last antenna that I tried it, after someone borrowed my usual throwing bucket.
Hello,
Thanks for the lengthy postings; lots of good reading there for this 'budding' QRPer.
I need to ask for you to clarify the first sentence above because I cannot picture the arrangement.
I have googled on what 'braided deep-sea fishing line' and 'paracord' look like.
I would like to try a portable antenna up into a tree again; my first and only attempt (done on vacation last year) ended up with me quite shaken because the fish-anchor somehow came back and almost hit me in the head. I don't know what went wrong but, if I try it again, I'll first make sure my life-insurance and health-insurance premiums are both paid-up.
TIA for any reply.
73 Jerry KM3K
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WB6BYU
Member

Posts: 16653




Ignore
« Reply #37 on: July 15, 2017, 05:46:20 PM »

Quote from: KM3K

...I need to ask for you to clarify the first sentence above because I cannot picture the arrangement.
I have googled on what 'braided deep-sea fishing line' and 'paracord' look like...



"Paracord" is standard parachute cord, a rather soft rope with kernmantle construction
(lengthwise strands inside, surrounded my a braided sheath).   This is great for a
lot of uses, but I find it often has too much friction when running over tree bark,
making it harder to get the other end back down to ground level when you do
get a weight up over a branch.  My favorite throwing lines have a tight, smooth
braid with less friction.

The fishing line was a guess - it was something given to me by a friend who knew
someone at a fishing shop where they replaced the line on reels when someone
bought net line. I assume it was used for salt-water fishing from a boat,
possibly for salmon or halibut.  I'd estimate it to be 50 to 200 pound test, and
and at least several hundred feet long.  If you wandered into your local
fishing shop and asked the would probably have something, or at least know
what it is (at least if they are near salt water.). Who knows, they might even
have some used line in need of recycling.  The exact choice of line probably
isn't important.


I know I've described the throwing buckets before:  a length of line flaked
into a bucket.  One end is tied to the bucket, the other has a throwing
weight, typically 4 or 6 oz of fishing weights inside a tennis ball.  It allows
the line to pay out smoothly when the ball is tossed without tangling on
grass or sticks.

The standard bucket is a 1 gallon plastic paint pail on sale for $1 at Ace
Hardware once a year, but other types will work.  The bucket with fishing
line happens to be a child's beach bucket I found somewhere.  I also
tried a plastic dish pan this year and it was easier to flake the rope into
it after each throw due to the wider opening.

I tie about a 4" loop on each no of the line (long enough for the tennis
ball to pass through) anduse a small clip like a carabiner on the bail to
attach it:  this makes it easier to swap ends of the rope when needed.
Starting at the end attached to the clip, just feel the line into the bucket
and let it fall as it may - don't worry about arranging it neatly.  The idea
is that the line pays out in reverse order to how it is put in, without
tangling on other stuff.  (The lighter line may benefit from a smaller
Buckner than the larger dish pan - experiment and finds what works best
for you.). The balls have a loop of light line sticking out that is attached
to the fishing weights.  Instead of a clip, I pass one of the loops through
the other and around the ball, making a simple knot that doesn't hand
up on the branches.  A fishing swivel would probably work as well.  The line
has to be at least twice the height of the branch you are aiming for in
order for the ball to make it back to the ground, and 2.5 to 3 times is
better as the line often passes over several branches.  My 80' bucket
is often too short, and 120' is sometimes marginal.  (You can always
o hook the end of the line from the bucket and add another rope to it.)

I certainly don't have a strong arm, but regularly get lines up to 50'
or 60'.  Folks watching say I make it look easy, but it really is.  I've had
a bit of practice over the years, of course...

The secret is to hold the rope about 2-3' from the weight - enough that
the ball can swing free without touching the ground with your arm hanging
down.  Spring it gently back and forth a few times to get the proper azimuth,
then let your arm follow it behind you on the back swing and fling it upwards
(underhand) at a fairly high angle.  It takes some practice to get it right.
This is much easier than trying to hrow overhand at a high angle.  You can
get more velocity (and hence distance) if you swing the ball in a circle, but
it requires more precise release timing to get it to go where you want it:
I don't find it helpful.

To do this, you have to be able to hold the rope well enough against the
pull of the ball as you accelerate it.  Soft leather gloves ate a good idea,
as it can cause rope burns across your fingers.  T can manage the
other lines OK, but the fishing line is too small to grip.  ( If you find the
ball flying off forward in a flat trajectory, you may not have enough grip
strength to hold it.)  To combat this I added a few feet of larger, softer
parachute cord to the throwing end, giving me a better grip, without
adding too much extra weight or friction.

I want to try the same bucket (without the parachute cord) with a dog
slingshot and a lighter ball or a fishing weight.  (The standard balls are
too heavy for the dog ball slingshot.). That might get me to 90+ feet,
which should be enough for most purposes.  In practice, 30' to 40' is
typically adequate for general portable use, but I like to maximize
performance for Field Day when I have tall trees available.

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AE0Q
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« Reply #38 on: July 16, 2017, 05:57:12 PM »


And for the QRPers, put out hundreds of watts but just tell folks
you're putting out 4.7 watts. It's not like anyone is going to check.

Kraus

Sheesh, must be why he got banned from QRZ years ago..

Either you run low pwr for the personal challenge, or you don't.

Glenn AE0Q
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Glenn and NATCH Katie,
NADAC Elite Versatility Award, O-WV-E, O-TG-E, HP-O, MXB, MJB, XF
http://www.hoopsandjumps.com/
http://funagility.webs.com/
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