Ferrite antenna/wireless coupler Q's?
DougC
ferrite rods sold online. The main radio I plan on using this with has
no AM antenna jack however.
I have seen the little stick-on magnetic couplers sold with some of the
loop and coil antennas--and I am guessing that this is another littler
ferrite rod (which I have one, pulled from a junk radio) but don't know
and can't find anything online that suggests what windings to use.
As a general assumption, how many turns should the antenna rod have, and
how many should the coupler have? Considering that we don't know the
number of windings on the radio's actual AM rod, nor do we know what
level is ideal for the radio's tuner circuit....
?
~
elaich
Just get one of the miniature variable caps they used in transistor radios
(if you can even find one any more!), wind the bar, and play with it. I put
mine in a vinyl channel, mounted the cap in the end, and lay it on top of
my DX-440. You can really peak up that untuned antenna circuit in that
thing, and you can get all kinds of interesting null/phasing effects by
moving it around in different ways and tuning it off frequency. I was told
I had reinvented the Quantum Stick.
UncleFester
better to couple the signal to the internal ferrite antenna of your radio.
Basic plan for all your tuned loop circuits. These things really do a good
job like "elaich" says.
Best place to find one of these tuning caps is from an older transisor radio
like the ones you can pick up at Value Village or Good ill for $1 or so.
Use the black and white wires of the ferrite antenna(largest winding) to
connect your variable cap to.
House the build in anything non metallic and convenient to use. That's it.
" I put mine in a vinyl channel". Sorry "elaich" but what exactly is
that? Maybe I could use it next build.
"elaich" <x@y.z> wrote in message news:6q5qh1F...@mid.individual.net...
elaich
@read2.cgocable.net:
> That's it.
> " I put mine in a vinyl channel". Sorry "elaich" but what exactly is
> that? Maybe I could use it next build.
>
It is actually a few scraps of vinyl siding from a construction site. I
cut them so they fit together to house the bar and cap. Oh, well, a
picture is worth 1,000 words.
Here's what I call the Ugly Stick:
http://img.villagephotos.com/p/2005-10/1085993/Picture062.jpg
Here's it's innards:
http://img.villagephotos.com/p/2005-10/1085993/Picture061.jpg
Here it is with the DX-440. No coupling is needed, as it inductively
couples to the interior ferrite bar.
http://img.villagephotos.com/p/2005-10/1085993/Picture063.jpg
As I mentioned, I can get all kinds of nulls and phasing by sliding it
around, rotating, tuning it. Since I live in a noise infested (RF wise)
apartment, this is the best compromise for me. It works great.
At night, KHTK/1140 is like a local for me. By sliding the stick around,
I could hear something underneath. A little more sliding nulled out KHTK,
and I could hear KGEM, Boise, ID. However, now that KHTK was
nulled/phased, I could hear something under KGEM.
A lot more tweaking and a KGEM fade got me CHRB, High River, Alberta. I
would never have logged this with a normal loop, since it would loop
right through the Idaho station. Some kind of phasing was needed.
It's a simple solution. YMMV.
UncleFester
Shack:
Sony 2010
Icom R75
Icom R71A
Drake R8
Grundig E1
Grundig 750
Grundig "800"
Grundig G5
Panasonic RF-4800
CCrane SW
Yaesu FRG-7700
"elaich" <x@y.z> wrote in message news:6q6db1F...@mid.individual.net...
RHF
DougC,
Thank You for making an On-Topic Shortwave Radio
Related Post here on Rec.Radio.Shortwave ~ RHF
.
RHF
Take a look at the QUANTUM STICK PLUS+
-aka- Q-Stick+ -by- DX Tools .Com
http://dxtools.com/QStick.htm
Also there is the "Quantum Coupler"
http://dxtools.com/QCoupler.htm
Make-Your-Own [DIY] Pocket Radio Coupler :
Just take an ordinary 'little' AM/MW Loop Antenna
http://www.tivoliaudio.com/images/P/ANT1_main.jpg
that comes with many AM& FM Radios connect a
Ground to one-side and an External Antenna that is
about 30~35 Foot long to the other-side and place
the 'little' Loop next to the Pocket AM & FM Radio.
iane ~ RHF
.