Indoor antenna
- Thread starter EJM3
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I have a RCA RV antenna in my attic that looks like a 3 foot plastic flying saucer from my Radio Shack brother years ago. The internal guts electrically rotate, with pre-amp circuitry and the mentioned FM trap coil. The trap coil is easily bypassed and the thing works pretty darn good. Don't know if they're still making these, but worth looking into. The FM's good and use it all the time for over the air Hi Def TV.
mhilton777
Well-Known Member
I recently picked up a Bic Beam Box off of fleabay for my TX-9800 and it works fantastic.
Remember seeing these things on display years ago. Pretty sure they've got a couple knobs moving some internal stuff around for fine tuning. Curious what's going on inside there.
Dark Knight
Well-Known Member
I once spent good money on an indoor antenna and posted on this. I was so dissapointed as it did not work better than a well-placed ribbon.
DK
DK
Bstable
Super Member
I bought an FM-8 30 years ago. I just got a Pioneer TX-9800. I have to restring the pioneer. I hope this combo works for me.
Bstable
Super Member
I can tell you there is not much going on inside. Somebody posted pics of the insides recently.
Tom Blasing
Super Member
I bought a Magnum Dynalab ST-2(?), mounted it in the attic with a single run of quad shielded coax and that thing pulls in like crazy.
JBL GUY
Addicted Member
Just like in real estate....It is location location location....even for an indoor antenna..
The half wave dipole antenna has been around for a very long time and in its implementation for FM reception is the standard "ribbon T" antenna...
And it will work well...But location and installation can make a huge difference..
It can be installed vertically or horizontally...and the feed line...the wire from the "T" to the tuner should be routed away from either end of the "T".
If it is installed horizontally in general it will pick up best broadside to the "T".
And if it is installed vertically in general it will be omni-directional...that is pick up about the same in all directions...
On of the problems receiving FM is something called multi-path distortion...this happens when the signal is reflected from some object and arrives at the tuner slightly delayed...
Moving the antenna may help...and keeping the feed line away from anything metallic will help reception. When it gets to the tuner keep it as far away fron any of the wiring at the back of it. And try and keep it as strait as possible and don't coil up any excess. And try to run the feed line at a right angle from the "T" for as far as you can.
Tv rabbit ears just another implementation of the dipole antenna...They have the ability to be "adjusted" for the best reception on a per station basis.
Most FM antennae are cut for the center of the band...usually making them about 60 inches long...30 inches for each half of the dipole.
With tv rabbit ears you can adjust the length for a particular station...longer for stations lower in frequency and shorter for stations higher in frequency.
If using rabbit ears just be sure they don't have an "FM trap".
Most cheap ones do not.
I am currently using a DIY FM dipole...I do have some multi-path issues with a few stations but I spent some time and found a location that gives good results for most of the stations I listen to. And since most of the stations I listen to are below 92 Mhz...I cut the length for the bottom of the band.
And in general the higher and more in the open an antenna is the better it will work...
Again location location location....that is why there are so many different opinions about antennae...One antenna that works good for one person may seem to be a poor performer for another person...
Having said all that...you may even get good reception by hooking up a couple of singe pieces of wire about 30 inches long to your receiver
And Tom that ST-2 looks like a good antenna and having it in the attic really helps...and +1 on having well shielded coax...some of the cheap stuff is sometimes less than 75 percent shielded.
The half wave dipole antenna has been around for a very long time and in its implementation for FM reception is the standard "ribbon T" antenna...
And it will work well...But location and installation can make a huge difference..
It can be installed vertically or horizontally...and the feed line...the wire from the "T" to the tuner should be routed away from either end of the "T".
If it is installed horizontally in general it will pick up best broadside to the "T".
And if it is installed vertically in general it will be omni-directional...that is pick up about the same in all directions...
On of the problems receiving FM is something called multi-path distortion...this happens when the signal is reflected from some object and arrives at the tuner slightly delayed...
Moving the antenna may help...and keeping the feed line away from anything metallic will help reception. When it gets to the tuner keep it as far away fron any of the wiring at the back of it. And try and keep it as strait as possible and don't coil up any excess. And try to run the feed line at a right angle from the "T" for as far as you can.
Tv rabbit ears just another implementation of the dipole antenna...They have the ability to be "adjusted" for the best reception on a per station basis.
Most FM antennae are cut for the center of the band...usually making them about 60 inches long...30 inches for each half of the dipole.
With tv rabbit ears you can adjust the length for a particular station...longer for stations lower in frequency and shorter for stations higher in frequency.
If using rabbit ears just be sure they don't have an "FM trap".
Most cheap ones do not.
I am currently using a DIY FM dipole...I do have some multi-path issues with a few stations but I spent some time and found a location that gives good results for most of the stations I listen to. And since most of the stations I listen to are below 92 Mhz...I cut the length for the bottom of the band.
And in general the higher and more in the open an antenna is the better it will work...
Again location location location....that is why there are so many different opinions about antennae...One antenna that works good for one person may seem to be a poor performer for another person...
Having said all that...you may even get good reception by hooking up a couple of singe pieces of wire about 30 inches long to your receiver
And Tom that ST-2 looks like a good antenna and having it in the attic really helps...and +1 on having well shielded coax...some of the cheap stuff is sometimes less than 75 percent shielded.
Don't know about you guys but over the years I've tried rabbit ears,ribbon you name it.No matter where I would set my units up basement,garage,living room always had a reception problem.Finally I tried a 6' length of 14 guage speaker wire and guess what? No more reception problems no matter which receiver or tuner I use no matter where they are.Signal strength meters are always very high in all types of weather conditions.Once in a while you might have to move the wire a bit but that's it........Rick....P/S Scott tuner,Awai receiver,Hitachi receiver,Marantz receiver,Pioneer tuner..with this all pull in nice and strong anywhere they are placed!
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AK 47
Well-Known Member
one thing often overlooked is diapole impedence. A simple diapole, cut to proper length has a natural impedence of 75 ohms, but is usuallt intalled as a 300 ohm antenna due to the simplicity of it. A folded diapole is terinated at 300 ohms and is what should be used connected to the tuner 300 ohm input.
that said, as stated above, location seems to be the most important factor when put to practical use.....and all the theory in the world does not seem to help much, and experimentation seems to work best.
I am using a Crane reflex antenna because it is terminated at 75 ohms and that is all my Technics ST 9030 FM only antenna has on the back.
Crane suggests varied, radical configurations and murphies law seems to apply here. I very carefully directed my Crane to NPR and confifured it horizontally and it worked well.
One of my cats decided to change it to a vertical on one leg :thumbsdn: and now it works better! :thmbsp:.....end results is what counts :drool:, Chuck
that said, as stated above, location seems to be the most important factor when put to practical use.....and all the theory in the world does not seem to help much, and experimentation seems to work best.
I am using a Crane reflex antenna because it is terminated at 75 ohms and that is all my Technics ST 9030 FM only antenna has on the back.
Crane suggests varied, radical configurations and murphies law seems to apply here. I very carefully directed my Crane to NPR and confifured it horizontally and it worked well.
One of my cats decided to change it to a vertical on one leg :thumbsdn: and now it works better! :thmbsp:.....end results is what counts :drool:, Chuck
JBL GUY
Addicted Member
AK 47
You are right on the money....It is kinda funny most of the cheap tv rabbit ears are simple dipole...yet the manufactures connect the 300 ohm twin lead right to the elements...
I am using a strait dipole with 75 ohm coax and and about 6 or 7 turns of coax coiled with a radius of about 2 inches for a "balun"...
I tried it with a general purpose TV balun...and it did not work as well...
So I put the balun an the analyzer and the 300 ohm side at 100Mhz was closer to 500 ohms and the 75 ohm side was closer to 25 ohms...took it apart and the build quality was very poor...by moving the windings on the ferrite and the lead dress I was able to improve it just a little...but still not good...I did not measure the caps that were in it...It was a DC blocking balun.
Yep that C. Crane antenna has gotten good reviews...I like the idea of a shielded feed line to the antenna....Less prone to pick up noise as it gets close to the rest of the audio gear....
You are right on the money....It is kinda funny most of the cheap tv rabbit ears are simple dipole...yet the manufactures connect the 300 ohm twin lead right to the elements...
I am using a strait dipole with 75 ohm coax and and about 6 or 7 turns of coax coiled with a radius of about 2 inches for a "balun"...
I tried it with a general purpose TV balun...and it did not work as well...
So I put the balun an the analyzer and the 300 ohm side at 100Mhz was closer to 500 ohms and the 75 ohm side was closer to 25 ohms...took it apart and the build quality was very poor...by moving the windings on the ferrite and the lead dress I was able to improve it just a little...but still not good...I did not measure the caps that were in it...It was a DC blocking balun.
Yep that C. Crane antenna has gotten good reviews...I like the idea of a shielded feed line to the antenna....Less prone to pick up noise as it gets close to the rest of the audio gear....
Quickie ...
Yup -B.I.C Beam box was a good one. Some still bring in big $. Hope you got your cheap?
Regular ZIP cord (lamp wire) can be used as a makeshift antenna. Split it so each end sticks out a 3 feet each way and run it into the 75 OHM connection. One leg into the screw-down and one to the 300 ohm terminal on many receivers. Keep clipping the ends until you get the highest signal strength for the station you like. Cheap and quick
Yup -B.I.C Beam box was a good one. Some still bring in big $. Hope you got your cheap?
Regular ZIP cord (lamp wire) can be used as a makeshift antenna. Split it so each end sticks out a 3 feet each way and run it into the 75 OHM connection. One leg into the screw-down and one to the 300 ohm terminal on many receivers. Keep clipping the ends until you get the highest signal strength for the station you like. Cheap and quick
mhilton777
Well-Known Member
Yup -B.I.C Beam box was a good one. Some still bring in big $. Hope you got your cheap?
Regular ZIP cord (lamp wire) can be used as a makeshift antenna. Split it so each end sticks out a 3 feet each way and run it into the 75 OHM connection. One leg into the screw-down and one to the 300 ohm terminal on many receivers. Keep clipping the ends until you get the highest signal strength for the station you like. Cheap and quick
I got the Beam Box FM-10 for $50 and there isn't a scratch on the plexi or on the box, so it is pretty much mint and works very well.