I'm trying to get better reception and build my own antenna. I've tried out a square full wave loop design I made out of some copper wire and a prebuilt dipole I picked up at the local electronics store to try it out. FM radio gets similar quality signal with or without dipole or square antenna, with just the coax connector on the radio without the antenna. I’m wondering why thats happening. Its an older model Radio Shack with the 300 ohm connector on the back for the vhf/uhf coaxial adapter. My goal is to try to pickup some of the weaker FM stations in Toronto.
How have you guys measured your reception strength? Has anyone else out there experimented with this by trying different antennas or receivers? What worked best for you?
How have you guys measured your reception strength? Has anyone else out there experimented with this by trying different antennas or receivers? What worked best for you?
Directional antennas help a lot, even just a pair of rabbit ears, preferably placed higher up.
If you really need some gain, it's best to get it with a more advanced antenna, instead of an RF amplifier.
https://www.gcaudio.com/tips-tricks/fm-antennas/
If you really need some gain, it's best to get it with a more advanced antenna, instead of an RF amplifier.
https://www.gcaudio.com/tips-tricks/fm-antennas/
Yagi's and a rotator are a way to get high gain FM reception, although a high gain collinear has the advantage of not needing rotating - however the FM band is quite wide which makes it trickier to design high gain arrays, whereas a Yagi is more straightforward
Multipath reception due to reflections and transmission of the signal along every metal pipe and wire in the building. You have to get up and out of such an environment for far-field behaviour (required for a high gain antenna, note).
In order to eliminate interference and have higher gain you need directional antena. Try to google 'rhombic fm antena'. Its big, but easy to construct if you have space in atic.
I use two element omnidirectional antena for local fm stations. For long distance i have four element yagi-uda.
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A while back, when over the air HD TV was getting started I looked into antennas to receive and record a CBC program (my cousin was gonna be on TV) I ended up with a Channel Master unit that I used to in Toronto. But during the investigations I made successful attempts from Markham. I remember watching an outdoor winter classic on a Toronto station and a Paul McCartney special on PBS.
Pointing was important.
...and you might take a look at fractal designs. For fun.
Pointing was important.
...and you might take a look at fractal designs. For fun.
An FM receiver amplifies the signal considerably, usually into clipping. It's not the amplitude that's needed so much as variations over time. Even your experimental method will not be good enough for a more distant station.
It can depend on the situation. I have one distant station to the east which I like to listen to, and one strong one to the west at a nearby frequency. I need to consider the front to back ratio of the antenna in this case.
Your tuners IF response is an important characteristic to consider as well as your antenna system. Sometimes you need narrow filters to reject adjacent carriers.
I'd build a small yagi antenna. Or maybe an HB9CV: https://www.qsl.net/dk7zb/HB9CV/Details-HB9CV.htm It's directional but not overly so, so it'll provide some gain for the weak stations without requiring it to be aimed at the station with micro-degree precision.
Tom
Tom
Am I too intrusive in asking if antenna type influences also FM noise? If my tuner is set to stereo, it is much much noisier than in mono ...
Analog FM tuners had 20 dB more noise in stereo than mono, due to the way the stereo information
was encoded in a subcarrier. So ten times the signal strength was required for the same quieting as in mono.
Naturally, the antenna would help if it has gain and directivity. Of course you can play stereo in mono to reduce noise.
was encoded in a subcarrier. So ten times the signal strength was required for the same quieting as in mono.
Naturally, the antenna would help if it has gain and directivity. Of course you can play stereo in mono to reduce noise.
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I've built a yagi for my summer camp. Wood stick 18" long, 2 3" aluminum sticks on end screwed at insides to 300 ohms/cable converter. Screw 300 ohm converter on inside of 2 short sticks with stainless steel 4-40 screws & elastic stop nuts. More aluminum sticks not separated 8", `10" 12" 14" 16" on 2" spacing down the stick. #6 wood screws for these. Narrow end with dipole points at transmitter. Muffler clamp through wood stick holds to iron pipe to hold it up off floor. My summer camp is 25 miles from transmitters.
The big seventes 10 element yagi outside ripped off the trailer & blew down. Bent the elements, which I sawed up for the inside yagi. I cannot put the 25' tall pole back up outside, that was done by professionals. We get much more frequent 90 mph wind gusts than they had in the seventies.
The big seventes 10 element yagi outside ripped off the trailer & blew down. Bent the elements, which I sawed up for the inside yagi. I cannot put the 25' tall pole back up outside, that was done by professionals. We get much more frequent 90 mph wind gusts than they had in the seventies.
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Lotta thanks. I thought some component was faulty. Pheww!! Pity, anyway … that noise is very annoying.
In addition to antenna concerns, there are big differences in tuner performance with marginal signals. Some of the classic designs are actually not all that great for this - they were made to sound good, not pick up good, if you follow.
Not sure if that's an option for you, but something to think about.
Not sure if that's an option for you, but something to think about.
Kumpa, there's a load of info about all this on the FM Tuner Info page https://www.fmtunerinfo.com/ - look at the left hand menu for options.
As for the original topic, I ended up making a simple aluminium dipole for my tuner, but in my research about this, downloaded the following antenna info from the above linked site. It's from a Carver tuner manual but is quite good.
As for the original topic, I ended up making a simple aluminium dipole for my tuner, but in my research about this, downloaded the following antenna info from the above linked site. It's from a Carver tuner manual but is quite good.