antenna
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I'm using the antenna discussed in this thread http://www.audiokarma.org/forums/showthread.php?t=202060 indoors. There are a lot antenna threads in this forum.
I'm using a Winegard 6010? omni on my roof at the moment...it does pretty good. Those $2.99 dipole do pretty good...except when you walk by them you mess us the signal.
Never had any luck with one in my attic...you need to get them on the roof. And make sure your leads are right.
Use 75 Ohm wire, make sure your connections are good...after that, the sky is the limit on antennas.
Chas
Never had any luck with one in my attic...you need to get them on the roof. And make sure your leads are right.
Use 75 Ohm wire, make sure your connections are good...after that, the sky is the limit on antennas.
Chas
I have always had good luck with the vintage BIC Beam Box. It is a selectable multi directional indoor antenna. They pop up on EBay now and then. There are several different models. The FM-6 and FM-8 models are on Ebay right now. I have an FM-10 which looks cool and works great. Do a google search on them. I have seen others comment highly about them also.
Gary
Timbo in Oz
Member
kind of depends!
you provide no information about your tuner, the number of stations of interest to you where you are, etc?
If there are only a handful or less / if they are all over the compass?
then we could really help.
there is a fairly sharp limiting function in place on how much a better FM tuner can do to compensate for a poor antenna.
For good sounding FM we need a strong signal (gain) that fully limits the front-end, and one that has low multipath. -----> A directional antenna!!
Few indoor antennas are any good, and when someone is happy with theirs they are either lucky, or have low expectations from FM - or both ;-).
The two basic types, the T (folded dipole made of TV twin wire ribbon) and the rabbit ears are good enough when you are close to the strong station and multipath is low inside your room. Even moving around can be a bad idea.
But there is one good indoor, but it is DIY and large, but you can hide it by pinning it to the ceiling or under rugs, or the new carpet you're getting?
Plan view is <> IE- a rhombic, and yes they are directional.
I am fortunate enough to have a national FM service that does not use any processing or compression and does several live broadcasts of simply-miked acoustic music per week, and several more broadcasts per week of recorded live concerts. The former source of audio is capable IME&O of being a true high end source, far better than any good simple stereo CD for example.
you provide no information about your tuner, the number of stations of interest to you where you are, etc?
If there are only a handful or less / if they are all over the compass?
then we could really help.
there is a fairly sharp limiting function in place on how much a better FM tuner can do to compensate for a poor antenna.
For good sounding FM we need a strong signal (gain) that fully limits the front-end, and one that has low multipath. -----> A directional antenna!!
Few indoor antennas are any good, and when someone is happy with theirs they are either lucky, or have low expectations from FM - or both ;-).
The two basic types, the T (folded dipole made of TV twin wire ribbon) and the rabbit ears are good enough when you are close to the strong station and multipath is low inside your room. Even moving around can be a bad idea.
But there is one good indoor, but it is DIY and large, but you can hide it by pinning it to the ceiling or under rugs, or the new carpet you're getting?
Plan view is <> IE- a rhombic, and yes they are directional.
I am fortunate enough to have a national FM service that does not use any processing or compression and does several live broadcasts of simply-miked acoustic music per week, and several more broadcasts per week of recorded live concerts. The former source of audio is capable IME&O of being a true high end source, far better than any good simple stereo CD for example.
nashvillebill
Super Member
I agree with Timbo; the rabbit ears and folded dipole (wire t-type) didn't work well at my location, even with very good tuners. I have had very good luck putting a square loop antenna in the attic, and decent success stapling a square loop to an indoor wall. This is a directional design with slightly better gain than a foldeed dipole. I started a thread on my success many months ago titled "Cheap homebrew antenna that works" or something like that. It's basically a square, with each leg 30 inches long, with a current balun to convert to 75 ohm coax.
bikezappa
Member
I bet the rabbitn ears would work even better if you put them in the attic.
Old_Tech
Yer-isn't!
300 Ohm Twin Lead
The basic 300 ohm twin lead dipole is very good when place well in the house. Tack it high on the wall. When using several recievers the dipoles can be overlapped slightly to aggregate the signal. You will find that as each receiver is powered on the signal strength will increase for the others. I am running three and have increased the signal strength from S4 to S5 doing this.
For outdoor, the omni-directional whip placed high will give outstanding results for distant stations. Stay away from amplified antennas they add noise while boosting gain. :yes:
The basic 300 ohm twin lead dipole is very good when place well in the house. Tack it high on the wall. When using several recievers the dipoles can be overlapped slightly to aggregate the signal. You will find that as each receiver is powered on the signal strength will increase for the others. I am running three and have increased the signal strength from S4 to S5 doing this.
For outdoor, the omni-directional whip placed high will give outstanding results for distant stations. Stay away from amplified antennas they add noise while boosting gain. :yes:
Timbo in Oz
Member
"For outdoor, the omni-directional whip placed high will give outstanding results for distant stations."
Your other points are fine as far as they go, but the above is just bullshit.
For good sounding results on FM in stereo, you need two things,
a strong enough signal from all stations to fully limit the front end, this will help with keeping noise low as well.
and a signal with little or no multipath so that Total Noise and distortion, is kept as low as possible.
A directional boom and elements type, with gain. The whips are not directional and have less gain than a dipole which is directional.
Read and absorb this report.
http://kalx.berkeley.edu/recept/antsurvy.htm
Lastly If you can put an antenna up outside above your house, and can afford the inflated prices of MD or fanfare for their marine whip antennas, why can't you put up a directional antenna and actually get some return on the investment in your tuner!
Mummy won't like it!?
Spare me!
Tim B
Your other points are fine as far as they go, but the above is just bullshit.
For good sounding results on FM in stereo, you need two things,
a strong enough signal from all stations to fully limit the front end, this will help with keeping noise low as well.
and a signal with little or no multipath so that Total Noise and distortion, is kept as low as possible.
A directional boom and elements type, with gain. The whips are not directional and have less gain than a dipole which is directional.
Read and absorb this report.
http://kalx.berkeley.edu/recept/antsurvy.htm
Lastly If you can put an antenna up outside above your house, and can afford the inflated prices of MD or fanfare for their marine whip antennas, why can't you put up a directional antenna and actually get some return on the investment in your tuner!
Mummy won't like it!?
Spare me!
Tim B
Timbo in Oz
Member
More for Old Tech(!!!!!???)
There is a far better option for long distance reception if you have a reasonable sized house block. A rhombic wire antenna with each element well over twice as long as lambda for FM at 88 meg.
Even an indoor one with elements around or less than lambda in length, and pinned to the ceiling are a good idea for distance listening. No you can't aim them, but I doubt many people have more than a handful of distant stations and many will be in the same town and effectively on the same axis. Most homes have several rooms to boot!
A rhombic has very good gain and a low multi-path signal and costs SFA to make.
tim B
There is a far better option for long distance reception if you have a reasonable sized house block. A rhombic wire antenna with each element well over twice as long as lambda for FM at 88 meg.
Even an indoor one with elements around or less than lambda in length, and pinned to the ceiling are a good idea for distance listening. No you can't aim them, but I doubt many people have more than a handful of distant stations and many will be in the same town and effectively on the same axis. Most homes have several rooms to boot!
A rhombic has very good gain and a low multi-path signal and costs SFA to make.
tim B
Timbo in Oz
Member
And, there's always the rhombic wire antenna option. DIY and very effective.
For those of us that are stupid or uneducated, will you offer some links or diagrams or something that will help us become more enlightened? Thanks.
KFCrosby
Active Member
The main drawback of Rhombics is the space required....
http://www.tpub.com/neets/book10/42o.htm
Or more antennas here
http://www.arrl.org/tis/info/antproj.html#menu
http://www.tpub.com/neets/book10/42o.htm
Or more antennas here
http://www.arrl.org/tis/info/antproj.html#menu
Timbo in Oz
Member
If a moderator would email me I can pass on a PDF copy of the article from the US magazine 'Audio' now defunct for lodging here as a reference. Or, individuals can receive a copy in their inbox after emailing me.
In plan-view a rhombic looks like this <>, it is two Vee antennas joined together, the antenna is loaded with R at the front.
the antenna's pattern is directional <>r ------> like so.
Each equal length element needs to be at least 0.7 lambda long.
You also need to 'orient' your house / its rooms onto a map so that you can point it/them correctly.
If you use 300 ohm TV ribbon to make them you have a double rhombic with about twice the gain. If you make the forward and rear angles narrower the pattern will narrow.
You can build two and spread them so the capture angle is wider, this is VERY useflu for covering a big but distant city's transmitters.
If you have a large house block or a farm-stead, four masts (trees?) can allow you to build an exterior one with very long sides and stacks and stacks of gain. But the build will be a bit more expensive.
I'm not an RF expert nor a ham even, but I've carried a few radios when I was a grunt, and learnt very quickly that the only advantage of whip antennas is their size.
? ......... Having to move around, so as to get through to another set, say with the artillery, is not always desirable for infantry ;-)! think about it.
I do have a whip - a Fanfare FM2G, it is on loan to my BIL's place of business in Yass about 40 miles line of sight away over flattish terrain from Canberra's big telecom tower on a big hill. It's a huge steel shed and yes the whip is up high and outside, it gives reasonable local reception IE < 10 miles range. It was given to me, I would never buy one.
the ABC claim 'adequate' coverage (ie not GOOD) out to and a bit beyond that range on that one flattish part of the target terrain. for the very powerful transmitters for the two national FM networks. Noting that the ABC has a charter that requires them to use very powerful transmitters.
http://www2b.abc.net.au/reception/frequencyfinder/asp/details.asp?transmissionid=894
Stereo is noisy but acceptable to the blokes working off both stations with the whip, and affected by aircraft and traffic on the road outside. I suggested they switch to mono and they now leave the mono button in all the time. It's an old Sanyo cassiever and el cheapo half-inch chipboard boomer spkrs.
Listening out
In plan-view a rhombic looks like this <>, it is two Vee antennas joined together, the antenna is loaded with R at the front.
the antenna's pattern is directional <>r ------> like so.
Each equal length element needs to be at least 0.7 lambda long.
You also need to 'orient' your house / its rooms onto a map so that you can point it/them correctly.
If you use 300 ohm TV ribbon to make them you have a double rhombic with about twice the gain. If you make the forward and rear angles narrower the pattern will narrow.
You can build two and spread them so the capture angle is wider, this is VERY useflu for covering a big but distant city's transmitters.
If you have a large house block or a farm-stead, four masts (trees?) can allow you to build an exterior one with very long sides and stacks and stacks of gain. But the build will be a bit more expensive.
I'm not an RF expert nor a ham even, but I've carried a few radios when I was a grunt, and learnt very quickly that the only advantage of whip antennas is their size.
? ......... Having to move around, so as to get through to another set, say with the artillery, is not always desirable for infantry ;-)! think about it.
I do have a whip - a Fanfare FM2G, it is on loan to my BIL's place of business in Yass about 40 miles line of sight away over flattish terrain from Canberra's big telecom tower on a big hill. It's a huge steel shed and yes the whip is up high and outside, it gives reasonable local reception IE < 10 miles range. It was given to me, I would never buy one.
the ABC claim 'adequate' coverage (ie not GOOD) out to and a bit beyond that range on that one flattish part of the target terrain. for the very powerful transmitters for the two national FM networks. Noting that the ABC has a charter that requires them to use very powerful transmitters.
http://www2b.abc.net.au/reception/frequencyfinder/asp/details.asp?transmissionid=894
Stereo is noisy but acceptable to the blokes working off both stations with the whip, and affected by aircraft and traffic on the road outside. I suggested they switch to mono and they now leave the mono button in all the time. It's an old Sanyo cassiever and el cheapo half-inch chipboard boomer spkrs.
Listening out
