Hello. I spent a night building a portable longwire out of scrap acetal,
stainless steel wire and a few other scrap parts. It works well but not as
fast to use as I'd like, and the shape for stowing means it's not a circular
coil and there is no guide to keep it winding easily without overrunning the
edge of the former.

To make something that can be set up and taken down so easily I could do it
at a run, I looked at two existing widgets that might do very well: Centrepin
fishing reels, and kite winders. I settled on the kite winder as being
slightly cheaper, more durable, etc.. eBay listing 270879102395 shows the one
I'm interested in. I haven't bought it yet, because a question remains...

Assuming I start at some tree on open ground and run the wire to where I want
to set up the receiver, I will usually leave some wire on the reel. The reel
is about 28 cm wide, about 25 mm along axis, and entirely made of stainless
steel. Is the metal attached to the antenna wire in this way going to affect
its ability too much, even if I take care to prevent electrical contact with
the ground?

Alternatively, I can lay in an plastic channel inside the reel to insulate
the wire from the rest of the reel, and modify the guide to contact the wire
while insulating it from the bulk of the wheel, which in turn might make a
convenience of a connector mounted on its chassis, so the bulk metal becomes
part of the ground, but then the question is this: Would the capacitance
formed across that insulating channel be enough to adversely affect the
longwire performance, bearing in mind that as well as LW I'm also interested
in using this method to listen to HF up to around 20 MHz too?

Another question.. I'm considering a similar (but less demanding) idea for
laying out radials for a temporary ground. For ease and speed these would
have to be laid out on the ground, and the receiver will be battery powered,
so this would be its only electrical reference to the ground. Is this ok, or
is there some better way to make a portable ground? Meaning, something I can
carry on foot for miles with little effort.

On Tuesday, September 9, 2014 12:47:29 PM UTC-5, Lostgallifreyan wrote:

Assuming I start at some tree on open ground and run the wire to where I want

to set up the receiver, I will usually leave some wire on the reel. The reel

is about 28 cm wide, about 25 mm along axis, and entirely made of stainless

steel. Is the metal attached to the antenna wire in this way going to affect

its ability too much, even if I take care to prevent electrical contact with

the ground?

No, it should be fine. I would prevent contact with the ground though.

Try a camping goods store -- find a camper's clothesline
reel. They are plastic and might just be what you need.

Irv VE6BP

wrote in news:3601a8a2-f915-4ff4-9d9b-
:

No, it should be fine. I would prevent contact with the ground though.


Thanks. I might make a box out of scrap plastic for it. I learned things
tonight that will lead to some redesign.

Irv Finkleman VE6BP wrote in
:

Try a camping goods store -- find a camper's clothesline
reel. They are plastic and might just be what you need.


Neat, and I like the totally enclosing design, but I think maybe too hard to
modify in useful ways. The kite winder looks most useful, I can mount a
socket on it, and hardware to anchor it easily in various ways. I even have
space to mount a small DC motor with idler wheel drive to the rim, and mount
a NiMH cell or two to operate it.

That sounds like overkill, but tonight after discovering just how amazing 50m
of stainless wire on high ground in open country can be, I found that my one-
night bodge with the scrap parts is ok for unwinding, just, and terrible for
winding. After ten metres I decided it was better to scrap the unwound wire
and bundle it into a pocket for later disposal, than to try to make my cold
fingers try to guide any more of it back onto my awful spool design in the
dark while stumbling on rough ground. I decided then and there that 100 quid
would not be too much to spend to never have to face that again. I think
I can get luxury for less than fifty, too. The main thing I want to figure
out will be stowing it at speed, even at a run. That will leave much more
time to be spent much more usefully.

For anyone reading this, and having any interest in the Tecsun PL-390 radio
and anything I said about it in other posts recently, here's the context so
far: With 100 turns on the end of the ferrite rod to modify it so the ring
terminal on the RF input jack is used for an AM longwire, instead of barely
detecting a Southampton NDB from Bristol, I now get several from France, the
furthest being Poitiers. As the Southampton NDB was detected by the
unaltered PL-390 with no possibility of external AM antenna, at 48 miles,
having only a 15nm range, the PL-390 is better at LW DX than many people
claim, and with the modification and a longwire, it's amazing.

"Lostgallifreyan" wrote in message
. ..
Hello. I spent a night building a portable longwire out of scrap acetal,
stainless steel wire and a few other scrap parts. It works well but not as
fast to use as I'd like, and the shape for stowing means it's not a
circular
coil and there is no guide to keep it winding easily without overrunning
the
edge of the former.


snip


Another question.. I'm considering a similar (but less demanding) idea for
laying out radials for a temporary ground. For ease and speed these would
have to be laid out on the ground, and the receiver will be battery
powered,
so this would be its only electrical reference to the ground. Is this ok,
or
is there some better way to make a portable ground? Meaning, something I
can
carry on foot for miles with little effort.

I have experimented with and demonstrated (ham fairs, Field Day) shortened
HF antennas, like the Hamstick and Hustler brands. These require radials
and I had been attaching them by nuts and bolts to the metallic base upon
which I place the mag-mount antenna. I carried several bases, each with
radials for a different band.

This is not your exact situation, I realize, but the latest version of my
radials might be useful: I have several short "pigtail" leads bolted to one
base. Each one is terminated in a banana jack and I have pre-cut pairs of
tuned radials with banana plugs on them. Several sets of my tuned radials
are ready to be unwound from foot-square cardboard frames, stretched out and
plugged into the jacks. The cardboard frames are simply the lids from
cardboard boxes. I notched out a few square inches at each end to form a
flat spool. Tangling is minimal. Presently I can deploy 8 radials. (Per
some discussions I have read, improvements gained by using more than 8
radials might not be audible.)

My radials are never exactly straight and it doesn't seem to matter. I have
not staked them, so to reduce the potential tripping hazard to the visitors.
I might use a small stone at the far end.

Your question, "Is this ok?" will be answered Yes by me. With only two
radial wires laid upon the ground, my antenna was entirely satisfactory.
From Southern California, we reliably worked the middle of the US with 100W
on 20m SSB during Field Day last year. However, having only two radial
wires gave a "best VSWR" no lower than 2:1 with the analyzer. The tuner
could fix that but adding another pair of radials brought the best VSWR down
to about 1.5:1.

I hope this also works for your long-wire. I am not at home, so I can't do
play-time for another week :-)

"Sal"
KD6VKW

Would a garden hose(pipe) reel work (30 cm-ish diameter)? used one for
microphone cords and it winds up nicely. I imagine alligator-clipping
onto the wire at the reel might do for a feed.

Eric Weaver wrote in
:

Would a garden hose(pipe) reel work (30 cm-ish diameter)? used one for
microphone cords and it winds up nicely. I imagine alligator-clipping
onto the wire at the reel might do for a feed.



How big are your pockets, exactly? Ok, I won't be pocketing a kite reel
any time soon, but it is somethign immediately manageable on foot for a few
miles. Last time I saw a hose reel it was a lot bigger than this kite reel. I
only need to spool a few hundred metres at most, of some thin stainless wire,
and possible another similar reel to take a few radial wires so I can quickly
lay them out. last time I tested, I had no need, I found a golf course, it
has these low metal platforms about the size of a small car, where people tee
off from. As I put 100 or so turns on one end of the ferrite rod, the current
that ground has to handle is very small anyway. Those little platforms seem
to make nice ground planes.

"Sal M. O'Nella" wrote in
:

This is not your exact situation, I realize, but the latest version of
my radials might be useful: I have several short "pigtail" leads bolted
to one base. Each one is terminated in a banana jack and I have pre-cut
pairs of tuned radials with banana plugs on them. Several sets of my
tuned radials are ready to be unwound from foot-square cardboard frames,
stretched out and plugged into the jacks. The cardboard frames are
simply the lids from cardboard boxes. I notched out a few square inches
at each end to form a flat spool. Tangling is minimal. Presently I can
deploy 8 radials. (Per some discussions I have read, improvements
gained by using more than 8 radials might not be audible.)


This is a nice idea. My current tests are LW AM so I'm only after enough
ground to get a reasonable current through the coil I put on the ferrite rod,
and so far, so good. (And LW radials could be very very long if I ever had to
transmit anything and do it right). I do want to try them for HF too though,
when I get into that, so thanks, this portable method looks like being
useful. I'd imagioned I might need up to 14 radials or so, but certainly all
the guidance I found says 20 or more is diminishing returns.

"Sal M. O'Nella" wrote in
:

Your question, "Is this ok?" will be answered Yes by me.

Ok. Any thoughts on the capacitance if I lay insulation into the kite reel
and leave spare antenna wire on it and ground the bulk of the reel? I'm
guessing it's not critical but I wouldn't want to mess up the tuning
frequency. A bit of lost signal I can manage.