That is a nice LOOP kit and it is for MW or for AM radio broadcast,
Yea you can copy that very easy, make an X frame with 2' sides, wrap
some wire (magnet, insulated, almost any really) around it to a AIR
Capacitor and you have a tunable passive loop. Here is a GOOD BASIC
You can copy his design exactly. The kit you talk of saves you from
scrounging for all the parts. There are not that many parts, but if
you don't have it you have to get it. THE DESIGN IS 100 YEARS OLD, no
You can make an untuned LOOP with out the capacitor. I just made one
out of a 1' x 1' pizza box and about 22' of wire, no capacitor. It
works well for my needs, to bring in a few near by AM stations. The
radio in question has no internal loop or loop-stick so I needed
something. It probably came with an untuned loop, no doubt that I
lost. Here is a link to the ultimate AM antenna and a pic of one I
built like it (I went 5 turns because I had the wire):
Here is my last post of thread on this antenna with pictures:
HOW DOES IT (tuned passive loops) WORK. The best explanation is a
swinging pendulum held in you hand. For a given weight hanging off a
string of given length, if you move your hand back and forth at a
certain rate (frequency) the weight at the end will react in a given
way. If you get the rate of hand moving back and forth just right
(for the string length & weight) it will swing wide (resonance). If
you move your hand back and forth faster or slower, the pendulum will
not move as vigorously or with regular movement. If you increase or
decrease the weight or length of string, it will react differently to
different freq of hand movement. SO WHAT DOES THAT HAVE TO DO WITH A
LOOP. Well the input or hand movement is the radio signal
(frequency). The string length is the length of the loop, and the
weight is the CAPACITOR! If you get the length of loop (number of
wraps around a frame of X circumference) and capacitor (weight at end
of string) just right for a given radio freq (hand movement) you get
the most resonance.
If you google LOOP antenna you will find web links for calculating
the range of "resonance" for a given loop, size, number of turns and
capacitor (capacitance) range.
The kit in question, if you varnish it and take your time will be
nice to look at and listen to. Like all passive loops, you have to
aim them and tune them. Of course you can make your own for cheaper.
The most expensive part is the air capacitor which is about $15-$20.
--- In email@example.com
, "Adam E." <gccradioscience@...>
> That sounds pretty hard, oops, my mistake, I got the wrong one.
> let me explain, there is a shortwave loop antenna that I want to
> on building soon a company called MTM Scientific made and they sell
> as a kit and I wanted to learn more about how to build one with
> readably available parts . I saw this kit and I thought it would
> fun to build since there is a frame and wire and other parts and
> pieces. If not possible I guess I will have to buy this kit soon.
> am still considering getting myself a copy of the JJ Carrs Loop
> Antenna Handbook for me to study when I am bored. Thanks for the
> help, its really appreciated.
> link: http://www.mtmscientific.com/swloop.html
> Adam E.
> Virginia Beach VA
> SWL Radios: Grundig YB-400PE, G5, Mini 300, S-350DL, FR-200. Radio
> Shack DX-380, 390, 392, 398. RY-611 and CF-1888
> --- In firstname.lastname@example.org, Chris Trask <christrask@>
> > >
> > > >
> > > > > Sorry but there is no link there except a Spanish forum that
> does not
> > > > > have any instructions in building a SW loop antenna. If
> anyone else
> > > > > can help that would be greatly appreciated thanks.
> > > > >
> > > > >
> > > > > Adam E.
> > > >
> > > > Adam; I agree with Jim. What do you want to build? ... untuned
> > > > loop? active loop? tuned passive loop? resonant cut
> > > > dipole?
> > >
> > >
> > > Tuned passive loop for to hang around by the window.
> > >
> > A wideband tuned passive loop will be very difficult to
> implement as the impedance of the loop will vary significantly. For
> instance, a 1 meter diameter loop consisting of 1 turn of 1/4"
> diameter copper tubing will have a resistance of about 0.5 ohms at
> 4MHz, 10 ohms at 12MHz, and then increases to 420 ohms at 15MHz.
> parallel resonance is around 17.9MHz. With a 4:1 BalUn transformer,
> such an antenna can be easily used for the 25M SWBC band without an
> > I went through months of building and testing loops of
> diamters, turns, and conductor diameters for my 2-part series onhttp://www.home.earthlink.net/~christrask
> active loops in the Jul/Aug and Sep/Oct 2003 issues of QEX.
> > Chris
> > ,----------------------. High Performance Mixers and
> > / What's all this \ Amplifiers for RF Communications
> > / extinct stuff, anyhow? /
> > \ _______,--------------' Chris Trask / N7ZWY
> > _ |/ Principal Engineer
> > oo\ Sonoran Radio Research
> > (__)\ _ P.O. Box 25240
> > \ \ .' `. Tempe, Arizona 85285-5240
> > \ \ / \
> > \ '" \ IEEE Senior Member #40274515
> > . ( ) \
> > '-| )__| :. \ Email: christrask@
> > | | | | \ '.
> > c__; c__; '-..'>.__
> > Graphics by Loek Frederiks