In article , Irv Finkleman
wrote:
With a one meter loop, a capacitor with a value of 100 pf
or less should beable to tune between about 7 and 30 mhz.
A 80 cm loop gives me reception between about 5 and 12 Mhz, this is with
a cap from a FM/AM radio kit ...
http://users.fulladsl.be/spb13810/oc/IMAG0018.JPG
So, to have higher freq, the loop should be made smaller ... (or higher
cap ?..)
I have made a loop (single turn too) of 2 X 3 meter, so its diameter is
close to 2 meter, and it gives me about 3? to 6Mhz ... African stations
on 5000-5100 come in very well here near Ypres / Belgium .... (at night)
http://users.fulladsl.be/spb13810/oc/IMAG0017.JPG
I used the 2 meter loop with 3 turns on 1600-1800khz, I could get a lot
of pirate stations from holland and ?? Greece or Serbia ...(at night)
Just turn the loop about 90? to switch between holland and Greece ...
In fact, yesterday I read a wiki about "large" loops (compared to freq,
they are large), on FM. I tried the 80cm loop on FM, and ... oops, it
is very directional, very good... I found stations I haven't had before
....
cite: "The (large) loop antenna is similar to a dipole, except that the
ends of the dipole are connected to form a circle, triangle (delta loop
antenna) or square. Typically a loop is a multiple of a half or full
wavelength in circumference. A circular loop gets higher gain (about
10%) than the other forms of large loop antenna, as gain of this antenna
is directly proportional to the area enclosed by the loop, but circles
can be hard to support in a flexible wire, making squares and triangles
much more popular. Large loop antennas are more immune to localized
noise partly due to lack of a need for a groundplane. The large loop has
its strongest signal in the plane of the loop, and nulls in the axis
perpendicular to the plane of the loop."
from
http://en.wikipedia.org/wiki/Antenna_%28electronics%29
--
een appeltje te schillen met
http://applefaulty.be
http://users.fulladsl.be/spb13810/bwnl.htm
Breng je iMac G5 terug (ik wil binnen 2 jaar geen defecte 2de hands Apple kopen)
http://www.apple.com/nl/support/imac...ensionprogram/