DIY FM antenna, can it be better than radioshack junk?

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I'm in love with the Moxon antenna. Never tried one for 75 ohm though, but according to this link: http://www.moxonantennaproject.com/fmdxer/The Indoor Moxon FM Antenna.pdf it's doable.
No need to use plastic pipes, I use a wooden frame, and for indoor use, it's more than enough.
It doesn't take much time to make one, and the result is well worth it.
Good luck with Your Dx'ing :D

Moxons are comparable in gain to a Yagi with one less element.
However, they are much broader bandwidth, and better null in back.
KD5ZXG Moxon Cell Yagi (4 elements) at that forum is mine...

Just a simple Moxon Rectangle might be a real good solution for
FM stereo reception. Though the impedance match and pattern
with only 2 elements tend to depend on several wave heights
above ground.

The 4 element Moxon cell Yagi is tolerant of neighbors. Good for
arrays or low installation height above its own ground reflection.

4NEC2X

CE Moxon Rectangle
GW 1 5 -0.046 0.0 0.25 0.0 0.0 0.25 0.00394
GW 2 31 0.0 0.0 0.25 0.0 0.0 0.62722 0.00394
GW 3 5 0.0 0.0 0.62722 -0.046 0.0 0.62722 0.00394
GW 4 5 -0.1043 0.0 0.25 -0.1583 0.0 0.25 0.00394
GW 5 31 -0.1583 0.0 0.25 -0.1583 0.0 0.62722 0.00394
GW 6 5 -0.1583 0.0 0.62722 -0.1043 0.0 0.62722 0.00394
GW 7 31 0.12535 0.0 0.62722 0.12535 0.0 0.25 0.00394
GW 8 31 -0.2921 0.0 0.62722 -0.2921 0.0 0.25 0.00394
GW 9 1 0.12535 0.0 0.62722 0.11323 0.0 0.62722 0.00394
GW 10 1 0.12535 0.0 0.25 0.11323 0.0 0.25 0.00394
GW 11 5 -0.2381 0.0 0.62722 -0.2921 0.0 0.62722 0.00394
GW 12 5 -0.2381 0.0 0.25 -0.2921 0.0 0.25 0.00394
GW 13 1 0.0 0.0 0.62722 0.01213 0.0 0.62722 0.00394
GW 14 1 0.0 0.0 0.25 0.01213 0.0 0.25 0.00394
GW 15 1 -0.1583 0.0 0.25 -0.1703 0.0 0.25 0.00394
GW 16 1 -0.1583 0.0 0.62722 -0.1703 0.0 0.62722 0.00394
GW 17 5 0.1095 0.0 0.25 0.05552 0.0 0.25 0.00394
GW 18 5 0.05552 0.0 0.62727 0.1095 0.0 0.62727 0.00394
GS 0 0 2.0534
GE 0
EX 0 2 16 0 1.0 0.0
GN 2 0 0 0 13.0 .005
FR 0 1 0 0 146.0 0.0
EN

Mind you, this was tuned for 2Meters. You will have to re-tune for FM broadcast.
 
Antennas work equally well transmitting or receiving - i.e. a good transmitting antenna is also a good receiving antenna. Otherwise it would disobey one of the laws of thermodynamics!

Not universally true.

Because you can transmit with 100% efficiency
from a dot with an ideal impedance match. And
you can add directional gain to that if you wish.

Receiving is equally improved by impedance
match and directional gain just like transmitting.
But only captures what tiny fraction of the total
transmitted energy that crosses it.

Bigger capture area is better when receiving.
Need to get over the receiver front end noise.
But doesn't matter to task of transmit.

The best impedance for receiving is best signal
to noise, not always the match for maximum
power transfer...
 
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K6STI (Brian Beezely) has posted a 10-element log periodic Yagi design with a phenomenal 40 db f/b ration; it's not an easy build but ranks up there with the best of past designs no longer commercially available.

Two Log-Yagis

Lots of other designs too, such as a circularly polarized quad that might be a good multipath fighter for analog FM stereo. It would be a somewhat easier build and more compact, too.

Circularly Polarized Cubical Quad
 
update on my swag

As a scientific wild *** guess (SWAG) it looks like you can locate the feedpoints for these other feedline impedances by taking the square root of the ratio of (desired impedance/50 ohm), and taking that resulting number and multiply it by the length from the bottom (shorted end of the J pole) the instructions tell you to place the 50 ohm coax connections.

Looks like my SWAG is off, that it's linear and not square root. According to

KJ6RZ and KH6HCU in their paper "copper pipe Jpole antennas"
The impedance at the bottom of the stub is approx 0 ohms, and very high at the top end where it is an open circuit. In the middle the stub is equal to its characteristic impedance. (paraphase here) which for twinlead is 300 ohms.
source http://home.windstream.net/tanders/files/copperjpole.pdf

So now it looks like you can locate the feedpoints for these other feedline impedances by taking the ratio of (desired impedance/50 ohm), and taking that resulting number and multiply it by the length from the bottom (shorted end of the J pole) the instructions tell you to place the 50 ohm coax connections. NO square rooting.

So now (for a Jpole cut for receiving radio stations in the FM broadcast band):

The length of twinlead is 0.66 meters for the stub, the length of wire is 1.4 meters, and the feedline connects, measured from the left,
for 50 ohm coax, 5.8cm
if my NEW SWAG is correct (for a stub made out of 300 ohm twinlead):
for 100 ohm twisted pair, like that in ethernet cat 5 cable, 11.6cm
for 300 ohm twinlead feedline, 33cm
for 75 ohm, 8.7cm


Oh and as far as antennas receiving as well as the transmit, look at the physical size of a dipole for channel 2 (big) vs one for channel 50 (small).
Both will transmit equally well, but on receive, the bigger dipole will intercept more signal.
 
I am not much at building stuff (hence my handle!) but based on much, much purchase of store-bought (= "crappy") FM antennae over the years, the only thing I've found that works well is a rooftop "TV" antenna.

My 2nd question is "what programming is there on FM that is worth listening to?" Perhaps your situation is different in Canada. I gave up on (home) FM years ago. I do still rarely listen to Jazz or other local on the rare stations here in the land of the homogenized playlist :(
 
My 2nd question is "what programming is there on FM that is worth listening to?"

Not a whole lot even in the NYC area. Depends on what music you want to listen to, of course. As for the homogenized playlists, I've been streaming some Australian radio stations, they appear to have different homogenized playlists, and in my case, oldies that were hits in Australia that USA didn't hear. It's like hearing oldies for the first time, new oldies. But some stations compress the audio stream too much and can sound yucky...
 
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