|
 |
LF Antenna design - RF Cafe Forums
|
| pollypocket
|
|
Post subject: LF Antenna design
Posted: Wed Oct 25, 2006 2:56 pm
|
|
Joined: Wed Oct 25, 2006
1:49 pm
Posts: 2
Location: ON
|
|
Hi;
I am looking for some guidelines for
LF 134Khz antennea. I install readers in some awkward
places and don't always need an off the shelf antenna.
I want to be able to construct a decent antenna
using 20 gauge multistrand wire in a loop(s)...speaker
wire or lamp cord. It is cheap and fast and should
be able to get the job done. Any advice besides
sticking to a commercial antenna?
thanks,
Paul
_________________
Ride Hard, Shoot Straight,
and Tell the Truth
|
|
| |
|
 |
|
nubbage |
|
Post subject:
Posted: Mon Oct 30, 2006 12:39 pm
|
|
| |
| General |
 |
Joined: Fri Feb 17, 2006
12:07 pm
Posts: 218
Location: London UK
|
|
| |
|
|
|
|
nubbage |
|
Post subject:
Posted: Tue Oct 31, 2006 4:32 am
|
|
| |
| General |
|
|
Joined: Fri Feb 17, 2006
12:07 pm
Posts: 218
Location: London UK
|
|
Hi Paul
Further to my earlier posting I found
this formula in an excel file I have built up over
many years of formula hunting. It gives the antenna
terminal voltage into an infinite load impedance
for a linear solenoid wound antenna of the type
you have in mind.
V = 7.89E-6*F*N*A*H0 volts
where
H0 = received field strength A/m
F = Freq in Hz
N = number of turns
A = area
in sq m
The value of H0 you would have to
estimate from known parameters for the transmitting
source and detection range.
I am not sure,
but someone else may know: if you tune the coil
and the total Q value is Q then the voltage becomes
V*Q at resonance (??)
|
|
| |
|
|
|
|
pollypocket |
|
Post subject:
Posted: Sun Nov 26, 2006 11:53 am
|
|
Joined: Wed Oct 25, 2006
1:49 pm
Posts: 2
Location: ON
|
|
Hi Nubbage;
Thanks for the advice and links.
I will have a look.
Regards,
Paul
_________________
Ride Hard, Shoot Straight,
and Tell the Truth
|
|
Posted 11/12/2012
|
|
|
|
|
