when to go aireal antenna?
- Thread starter c3conv
- Start date
Simple test: Switch from stereo to mono - if you hear the noise level decrease, then a better antenna probably will help.
What do you mean by noise level? Added sound asside from the music? Any other way to test this?old_tv_nut said:
I have this favorite station, the problem is that it still can not trigger the FM STEREO indicator light at signal level 4. unlike the other station it lights up at lelvel 3. That's why I am asking if it will improve the sound or not. If it will I will get hold of an aerial.
Paul C
Super Member
When I do listen to a weak, distant station that is noisy, of course, switching to mono will many times clean up the sound. My preamp and a receiver both have a simulated stereo feature I can switch on. This does a pretty good job.
But I would much rather listen to clean mono than noisy stereo.
There is this GREAT jazz station I can sometimes pick up at night, but its about 200 miles away.
But I would much rather listen to clean mono than noisy stereo.
There is this GREAT jazz station I can sometimes pick up at night, but its about 200 miles away.
c3conv said:
I meant background hiss from a weak signal - if your receiver has a power meter, and it's already at a high level, a stronger antenna won't help with basic noise, because there isn't any. Hiwever, if you're getting interference or distortion on a particular strong station, a more directional antenna might help.
In addition to boosting signal strength, a quality antenna (properly installed of course) can help to eliminate noise and improve the listening experience in a couple of ways....
1, A directional antenna can help to eliminate interference from other broadcast sources.
2. Locating the antenna away from electrical equipment (computers, appliances, fluorescent lighting, etc..) , and using a good quality sheilded coax antenna cable can help isolate sorces of background noise and hiss/hum.
3. Multipath interference can be reduced by using a more directional antenna.
1, A directional antenna can help to eliminate interference from other broadcast sources.
2. Locating the antenna away from electrical equipment (computers, appliances, fluorescent lighting, etc..) , and using a good quality sheilded coax antenna cable can help isolate sorces of background noise and hiss/hum.
3. Multipath interference can be reduced by using a more directional antenna.
Paul C said:
Are you talking about AM or FM for this range. I would assume FM because there aren't too many receivers out there that can receive stereo AM, also there are not too many, probably just a handful of stations that transmit AM stereo.
Now I know someone is going to tell me it's impossible to transmit stereo amplitude modulation.
Paul C
Super Member
I had a good outdoor antenna, lost due to storms. I live in a very flat coastal area. I have an antenna in the attic right now but it is not doing the job. I'll be going back to an outdoor antenna soon.
I was picking up an FM station 200 mi away, sometimes at night.
Even now, with just a pc of wire on my two receivers and the attic antenna on my main system tuner, I can easily pick up stations 50-60 miles away. Some in stereo, some a little noisy, have to go to mono.
I was picking up an FM station 200 mi away, sometimes at night.
Even now, with just a pc of wire on my two receivers and the attic antenna on my main system tuner, I can easily pick up stations 50-60 miles away. Some in stereo, some a little noisy, have to go to mono.
How about underwater?kc8mob said:
I find the tuner makes a large difference. I use a TV antenna with a masthead amp. With a Sony tuner I can pick up dozens of stations clearly. With a NAD, I can pick up maybe a dozen, and none is noiseless. With a middle of the road hifi reciever I get a few very clearly, and many not.
Ok Ok, Im going to post plans to a dual stacked 5/8 wave antenna.
Also, I would try staying away from receive pre-amps. They bring in everything, even Santa's sleigh bells.
If you use a stacked 5/8 wave and you can achieve some hight you should do very well for your self. I live about 17 miles north of the river here and I can hit a repeater in Indianapolis, and that's running a Icom 2100H on a stacked 5/8 wave. (55 watts out)
This is a ground plane antenna btw.
Also for you guys who get incorrigible interference on a certain part of the band, I have the solution for you chaps too.
Use a 1/4 wave trap. Now it's really easy to make, and will kill any and all intermod you may be getting. So if it's the not the frequency you want, you won't get it.
1/4 wave trap: Determine the frequency you wish to center this trap on. Get an extra piece of coax that is a 1/4 wavelength of this determined frq. Then multiply the velocity factor of the coax by the quarter wavelength and thats your piece of cable. ( It's going to be a decimal point, like .95 for 95%) Now you can install this like a "T" it doesn't matter where in the cable run, just install it with a 'T' connector. Use 'F' connectors if you can or even better PL-259 or SO-239 jobbies. Now here is the weird part. At the end of the 1/4 wavelength of cable, connect the shield to the center conductor, yes short them together. Use a switch though, this is a narrow filter and you would want to remove it out of the line and maybe switch in another one on a different part of the band.
SHORT THE END OF THE 1/4 WAVELENGTH CABLE.
Now if you study antennas and transmitters, receivers you would find that at the determined frequency your receiver or transmitter for that matter will see an open circuit because it is at 1/4 wavelength. This means that the frequencies you want will not be shunted to ground, but the crap you do not want like harmonics and intermod from god knows what will be shorted out and become nonexistent before your receivers front end tries to demodulate the garbage.
WHAT.....? Yes that is true.
Ok now I just have to scan some plans I have of my antenna I made, We can adjust it for FM broadcast band without any problem.
Also, I would try staying away from receive pre-amps. They bring in everything, even Santa's sleigh bells.
If you use a stacked 5/8 wave and you can achieve some hight you should do very well for your self. I live about 17 miles north of the river here and I can hit a repeater in Indianapolis, and that's running a Icom 2100H on a stacked 5/8 wave. (55 watts out)
This is a ground plane antenna btw.
Also for you guys who get incorrigible interference on a certain part of the band, I have the solution for you chaps too.
Use a 1/4 wave trap. Now it's really easy to make, and will kill any and all intermod you may be getting. So if it's the not the frequency you want, you won't get it.
1/4 wave trap: Determine the frequency you wish to center this trap on. Get an extra piece of coax that is a 1/4 wavelength of this determined frq. Then multiply the velocity factor of the coax by the quarter wavelength and thats your piece of cable. ( It's going to be a decimal point, like .95 for 95%) Now you can install this like a "T" it doesn't matter where in the cable run, just install it with a 'T' connector. Use 'F' connectors if you can or even better PL-259 or SO-239 jobbies. Now here is the weird part. At the end of the 1/4 wavelength of cable, connect the shield to the center conductor, yes short them together. Use a switch though, this is a narrow filter and you would want to remove it out of the line and maybe switch in another one on a different part of the band.
SHORT THE END OF THE 1/4 WAVELENGTH CABLE.
Now if you study antennas and transmitters, receivers you would find that at the determined frequency your receiver or transmitter for that matter will see an open circuit because it is at 1/4 wavelength. This means that the frequencies you want will not be shunted to ground, but the crap you do not want like harmonics and intermod from god knows what will be shorted out and become nonexistent before your receivers front end tries to demodulate the garbage.
WHAT.....? Yes that is true.
Ok now I just have to scan some plans I have of my antenna I made, We can adjust it for FM broadcast band without any problem.
kc8mob said:Ok Ok, Im going to post plans to a dual stacked 5/8 wave antenna.
Also, I would try staying away from receive pre-amps. They bring in everything, even Santa's sleigh bells.
If you use a stacked 5/8 wave and you can achieve some hight you should do very well for your self. I live about 17 miles north of the river here and I can hit a repeater in Indianapolis, and that's running a Icom 2100H on a stacked 5/8 wave. (55 watts out)
This is a ground plane antenna btw.
Also for you guys who get incorrigible interference on a certain part of the band, I have the solution for you chaps too.
Use a 1/4 wave trap. Now it's really easy to make, and will kill any and all intermod you may be getting. So if it's the not the frequency you want, you won't get it.
1/4 wave trap: Determine the frequency you wish to center this trap on. Get an extra piece of coax that is a 1/4 wavelength of this determined frq. Then multiply the velocity factor of the coax by the quarter wavelength and thats your piece of cable. ( It's going to be a decimal point, like .95 for 95%) Now you can install this like a "T" it doesn't matter where in the cable run, just install it with a 'T' connector. Use 'F' connectors if you can or even better PL-259 or SO-239 jobbies. Now here is the weird part. At the end of the 1/4 wavelength of cable, connect the shield to the center conductor, yes short them together. Use a switch though, this is a narrow filter and you would want to remove it out of the line and maybe switch in another one on a different part of the band.
SHORT THE END OF THE 1/4 WAVELENGTH CABLE.
Now if you study antennas and transmitters, receivers you would find that at the determined frequency your receiver or transmitter for that matter will see an open circuit because it is at 1/4 wavelength. This means that the frequencies you want will not be shunted to ground, but the crap you do not want like harmonics and intermod from god knows what will be shorted out and become nonexistent before your receivers front end tries to demodulate the garbage.
WHAT.....? Yes that is true.
Ok now I just have to scan some plans I have of my antenna I made, We can adjust it for FM broadcast band without any problem.
I am no tech guy, can you please post some pictures if you can? can you provide us an example like for example you are trying to get 1051 MHz?
Ok to figure out a quarter wavelength in coax for 105.1 MHz we do this.
For inches:
11,811 divided by 105.1 =112.378687. Now this is a full wavelength so divide that number by 4. Which is: 28.09467174. Feel free to round off.
Now that is the wavelength in free space as a electromagnetic wave form.
We are dealing with coax. So if you use 50 ohm coax, it has a velocity factor of 95%. then take that number 28.1 and multiply it by .95 which equals: 26.68993815.
So 26.69 inches is the length of you coax.
I strongly recommend people use 50 ohm coax even if there receivers say "75 ohm" on the antenna jack. 75 ohm is used because you can get it everywhere, where as 50 ohm coax is only sold for communications in general. That is unless you really believe your antenna has a characteristic impedance of 75 ohm.
Im going to post a page dedicated to antennas and wires and coax and why not to get hit by lightning later tonight. :thmbsp:
hahahahaha I bet you guys wish you had an MFJ antenna analyzer right about now. LOL
Sorry
For inches:
11,811 divided by 105.1 =112.378687. Now this is a full wavelength so divide that number by 4. Which is: 28.09467174. Feel free to round off.
Now that is the wavelength in free space as a electromagnetic wave form.
We are dealing with coax. So if you use 50 ohm coax, it has a velocity factor of 95%. then take that number 28.1 and multiply it by .95 which equals: 26.68993815.
So 26.69 inches is the length of you coax.
I strongly recommend people use 50 ohm coax even if there receivers say "75 ohm" on the antenna jack. 75 ohm is used because you can get it everywhere, where as 50 ohm coax is only sold for communications in general. That is unless you really believe your antenna has a characteristic impedance of 75 ohm.
Im going to post a page dedicated to antennas and wires and coax and why not to get hit by lightning later tonight. :thmbsp:
hahahahaha I bet you guys wish you had an MFJ antenna analyzer right about now. LOL
Sorry
increased signal strength will improve sound quality up to the point of full quieting, after that it can actually cause problems with overload of the front end letting stations on other frequencies in the passband mix with the desired station causing intermodulation distortionc3conv said:
am stereo is possible and its called cquam, but it still doesnt have the bandwidth available at higher frequencies used by fm broadcast. my sencore am fm signal generator has am stereo although ive never needed it, and i also have an am stereo radio in my old truck i drive to work.kc8mob said:
