Cheap antenna options?

[I LIKE MUSIC]

There is no question about the science and physics involved in antenna design.

But, I'm talking one of the old triple tier antennas used in the late sixties to early seventies.

I am not sure what you mean by triple tier, three separate antennas (VHF low band, VHF high band and UHF) stacked or a single combination antenna. There are some of each in my graph and none are stellar performers on the FM broadcast band.

The smaller two tier TV antenna has to be rotated to pick up staitions in full strength

By this are you saying that a "3 tier antenna" is not directional, that is it would not have to be rotated? Basic antenna theory tells us that it is not the number of "tiers" that causes an antenna to be directional. A basic dipole antenna is directional to its broadside and a basic yagi antenna is directional.

It is true that some TV antennas may be better than others in terms of FM broadcast band reception, but your original suggestion did not make any qualification regarding the specific antenna. This could lead a person that is not familiar with antenna design theory to choose an antenna that is completely inappropriate.

TV antenna will more than just do the trick

While it is true that any piece of wire stuck up in the air will receive some signal, that does not mean that it is optimum.
There will be situations where even a deep fringe, high gain FM broadcast band antenna may not be sufficient for the stations of interest.

Saying that a TV antenna will more than do the trick is not correct and can be misleading. Again it is all about the amount and quality of the signal seen be the antenna. It is not going to be the same for everyone and what may work okay for some may not work so well for others. What may have worked for you may not necessarily work okay for others.

Note that even the best of the antennas in the graph has only a couple of dBd of gain above the lowest frequencies of the FM broadcast band and most of them exhibit negative gain. That is gain that is considerably less than a basic dipole antenna at frequencies greater than about 92 MHz.

Below is is picture of the best antenna shown in my graph in terms of FM broadcast performance. It is a combo VHF low, VHF high and UHF TV antenna. It is not a small antenna will have appreciably more wind loading than an FM antenna requiring a more robust and likely more expensive installation. Most of the elements of the antenna have no function for the reception of FM.

TV antenna will more than just do the trick

Base on your suggestion, how is person without knowledge in the science and theory of antenna design going to know how a given TV antenna will perform for FM broadcast band reception? And you make this statement without regard to the RF field strength for a given location. For those that are located in moderate strong to strong RF field strength coverage areas for their stations of interest, the choice of antenna may not be that critical. But for those that are located in areas of weaker RF field strength, the correct choice of antenna becomes much more important.

If a person would like to experiment with a TV antenna for FM reception that is fine. But that does not change the science and physics of the design and performance of antennas. Blanket recommendations may provide inaccurate information.

 

[I LIKE MUSIC]

I took a look at the RF field strength contours of some FM stations in San Francisco.



Note that San Jose is in the "local area" in terms of RF field strength and it would likely not take much of an outdoor antenna to provide good reception.

The TV antenna that you used may have had fairly good performance for FM reception, but your example, without reference to the brand/model of the antenna is just that a single example that does not support a blanket statement regarding FM performance of TV antennas.

These maps are used by the radio stations to help determine advertising rates and are fairly accurate, although as I have mentioned, there can be individual variation in signal strength. A station can say that it has a certain coverage area and can reach X number of listeners.

 

[Djcoolray]

I took a look at the RF field strength contours of some FM stations in San Francisco.

View attachment 953778

Note that San Jose is in the "local area" in terms of RF field strength and it would likely not take much of an outdoor antenna to provide good reception.

The TV antenna that you used may have had fairly good performance for FM reception, but your example, without reference to the brand/model of the antenna is just that a single example that does not support a blanket statement regarding FM performance of TV antennas.

These maps are used by the radio stations to help determine advertising rates and are fairly accurate, although as I have mentioned, there can be individual variation in signal strength. A station can say that it has a certain coverage area and can reach X number of listeners.

Haven't you seen any of the old triple stacked TV antennas on huge old two story houses that some old people have owned forever? I'm not trying to get smart with you or anything, but really. Maybe I'm expecting too much from a less observant populous. Heck, Curtis Mathis put them up on houses free with everyone of their magnanimous color TV's. I still see them up on houses in older neighborhoods. The TV antenna your showing is a modern single stack....tier antenna. I'm not talking about different bands or capabilities here, I'm talking three stacks of antenna with about two feet separating the layers and angled in different directions. The reason why this situation of people referring to these antenna is because you can hook up anything to it and get awesome reception. I hooked up a Pioneer TX-9500 series II Tuner with two pair of B&O speakers and surprised everyone I knew at that time. Clarity beyond the imagination of possibility. I've also seen great results with double stacked and single antenna similar to the picture your showing. I've known friends of mine to utilize the antenna on the house that they are renting, they'll take it down polish it up and reinstall it to obtain maximum clarity. People have been doing this forever, albeit not as often today as industry dictates that people purchase goods over doing things for themselves. Sorry if I was raining on your parade....

 

[Mamrak1]

If you have access to place an outdoor antenna, a Channel Master rotor for a mast pole and antenna is an ideal combo. You can dial your antenna to any direction without stepping outside.

 

[I LIKE MUSIC]

Haven't you seen any of the old triple stacked TV antennas on huge old two story houses that some old people have owned forever? I'm not trying to get smart with you or anything, but really. Maybe I'm expecting too much from a less observant populous.

I was born before the transistor was invented. I started my own electronics shop at an early age. I have installed, on a professional basis, many types of antennas. I have done on site RF field strength analysis for stations of interest in order to create an RF link budget.

A link budget is the term used that accounts for the power received at the receiver. This accounts for all of the gain and losses from the transmitter to the point at which it is received by the receiver. In terms of this discussion we are talking about the gain (performance) of the receiving antenna and the amount of signal (RF field strength) that it sees.

I have worked as an RF design engineer. No matter what the antenna, the physics of antenna design and antenna performance apply. Blanket statements about undefined antennas do not supply accurate information.

I have been involved with the design and deployment of antennas used for deep space communication and radio astronomy. I am not a member of your so called "less observant populous" in terms of antennas, their design, use and implementation.

I'm not talking about different bands or capabilities here

Different bands and capabilities, this is basic antenna design 101. Either an antenna is being used for the frequency range that it is designed for, where it will work the best or it is not and in that case it will not work the best. Either it supplies the needed amount of gain, directionality, front to back ratio and side rejection or it does not. This is basic antenna theory 101.

If you you disagree with this and it seems that you do, please show me the math, theory and antenna design to support it. Show me how an antenna that has 10 dB less gain as some TV antennas do in FM broadcast band, as shown in the graph that I posted, can work as well as an antenna with higher gain, such as a purpose designed FM antenna when it comes to weak signal reception. Show me the math, theory and antenna design, not just hyperbole.

A lot of hyperbole does not change the laws of physics with regard to antenna performance. One persons experience does not lay the ground work for blanket statements.

I took issue with your original statement.

For sixty miles cheaply I'd find an old TV antenna

It is a blanket statement that does not apply in all situations. You did not define what you meant by "old TV antenna". It could be a TV VHF high band only antenna or a TV UHF only antenna or a TV cut channel antenna, none of which will work very well for an FM broadcast band antenna. You did not define the RF field strength as seen by the antenna. You still have not given a good definition of the antennas of which you speak. You just call them old TV antennas on old houses.

Again, it is all about the amount and quality of the RF signal as seen by the antenna being used. There may be a situation where an old TV antenna will provide the needed performance and there will be times when it will not.

But when it comes to the reception of weaker signals it is more than very likely that a purpose designed, gain type FM antenna will outperform an old TV antenna (an undefined antenna at that) and your blanket statement will not be correct. This is just basic antenna theory.


Although some may have, It is safe to say that not everyone here has a background in antenna theory and design and will they not be able to predict the FM performance of a generic "old TV antenna" and its suitability for a particular FM broadcast reception application. This is my point about your blanket statement.

Ryan, I am sorry that your original post has been side tracked. The incorrect myth of using just any "old TV antenna" without defining the antenna and the circumstance of its use is misleading at best.

What kind of FM reception to you get with a basic FM dipole antenna? How is the reception using your car radio? Do you have an attic where you could install an antenna? Are all of your stations of interest in the same direction? Where are you located and what are your stations of interest?

 

[Djcoolray]

I was born before the transistor was invented. I started my own electronics shop at an early age. I have installed, on a professional basis, many types of antennas. I have done on site RF field strength analysis for stations of interest in order to create an RF link budget.

A link budget is the term used that accounts for the power received at the receiver. This accounts for all of the gain and losses from the transmitter to the point at which it is received by the receiver. In terms of this discussion we are talking about the gain (performance) of the receiving antenna and the amount of signal (RF field strength) that it sees.

I have worked as an RF design engineer. No matter what the antenna, the physics of antenna design and antenna performance apply. Blanket statements about undefined antennas do not supply accurate information.

I have been involved with the design and deployment of antennas used for deep space communication and radio astronomy. I am not a member of your so called "less observant populous" in terms of antennas, their design, use and implementation.



Different bands and capabilities, this is basic antenna design 101. Either an antenna is being used for the frequency range that it is designed for, where it will work the best or it is not and in that case it will not work the best. Either it supplies the needed amount of gain, directionality, front to back ratio and side rejection or it does not. This is basic antenna theory 101.

If you you disagree with this and it seems that you do, please show me the math, theory and antenna design to support it. Show me how an antenna that has 10 dB less gain as some TV antennas do in FM broadcast band, as shown in the graph that I posted, can work as well as an antenna with higher gain, such as a purpose designed FM antenna when it comes to weak signal reception. Show me the math, theory and antenna design, not just hyperbole.

A lot of hyperbole does not change the laws of physics with regard to antenna performance. One persons experience does not lay the ground work for blanket statements.

I took issue with your original statement.



It is a blanket statement that does not apply in all situations. You did not define what you meant by "old TV antenna". It could be a TV VHF high band only antenna or a TV UHF only antenna or a TV cut channel antenna, none of which will work very well for an FM broadcast band antenna. You did not define the RF field strength as seen by the antenna. You still have not given a good definition of the antennas of which you speak. You just call them old TV antennas on old houses.

Again, it is all about the amount and quality of the RF signal as seen by the antenna being used. There may be a situation where an old TV antenna will provide the needed performance and there will be times when it will not.

But when it comes to the reception of weaker signals it is more than very likely that a purpose designed, gain type FM antenna will outperform an old TV antenna (an undefined antenna at that) and your blanket statement will not be correct. This is just basic antenna theory.


Although some may have, It is safe to say that not everyone here has a background in antenna theory and design and will they not be able to predict the FM performance of a generic "old TV antenna" and its suitability for a particular FM broadcast reception application. This is my point about your blanket statement.

Ryan, I am sorry that your original post has been side tracked. The incorrect myth of using just any "old TV antenna" without defining the antenna and the circumstance of its use is misleading at best.

What kind of FM reception to you get with a basic FM dipole antenna? How is the reception using your car radio? Do you have an attic where you could install an antenna? Are all of your stations of interest in the same direction? Where are you located and what are your stations of interest?

I'm not trying to mislead you, I just used one of those huge TV antennas to pull in some underground San Francisco FM staitions allot clearer. Then there was a rebroadcast of Don Cornelius's radio show coming out of Oakland that was a bit weak and the antenna pulled it in real strong. Your definitely over thinking this situation, it's just a signal and some polished aluminum...at least I think it was aluminum. The antenna was behind a big two story house that I rented and in the process of repainting the house, I cleaned up the antenna and reinstalled it. Nothing really major as I am not a rocket scientist like you are, I'm just some working slob that was a jack of all trades but a master of auto mechanics and auto body. I've always found a way to put things together and make them work out of necessity. I've done some minimal electrical repairs, but nothing major. But as to your reaction of all this I'd say your definitions are technically narrow as to the possibilities of what can happen. But I do remember having to ground one of the two antenna wires to the chassis of the receiver to get the best reception. I'm sorry if you blew a fuse over this one.....a nice big mug of hot green tea and raw honey is a good de-stressor !! There are endless possibilities in this world and curiosity is the key to considering them. You know I'm not the only one that has done this....to pull in radio stations clearer than I could already receive. I already could receive the radio stations, I was just going for increased clarity and definition as many do in the South Bay Area code of 503.....is where I wish I could be !

You have a nice day now.....yah here !!!!

 

[the skipper]

OK, I'll probably take heat from both sides here but I think we're all over complicating this matter. I'l l just share my experience with antennas,.

Yes, antennas can be optimized for a purpose; You can get single purpose antennas for FM, UHF and even VHF. They will outperform a similarly sized/price "all in one" antenna, without doubt

Likewise, a pure FM antenna will outperform a similarly sized VHF/UHF/FM,the likes of which were sold in droves from the 60's up into the 2,000 when digital TV became more popular, There are still a bunch out there that are till functional. I have an RCA antenna we put up in '73 or so and it's still going strong.

They were designed mainly for VHF because that's what a majority of people card about. FM was thrown in "free" in many cases What with the FM band falling conveniently between channels 6 and 7, they could work fine for FM as well, Maybe not as well as a similarly sized "FM only" antenna, but can still do a pretty good job for most applications. Yes, some antennas had an FM block but these were pretty far and few between. On the whole, most users were very satisfied with these combo units. Even me. I used if for both TV and FM and was happy as a seagull with a french fry.

Now, with UHF becoming more popular, thanks to digital TV, these "old school" combo antennas are becoming less readily available but, at one time, just like the dinosaurs ruled the earth, they ruled the rooftops of the world.

If you want to get an idea of how popular these were, check out the selection in these catalogs here. http://www.radioshackcatalogs.com/

Now, I'm not saying that dedicated antennas were useless, They aren't. In some cases if their job is to one dedicated purpose, it's the best way to get the maximum results, This was true when we used 28' dishes for microwave communication in the Air Force and, yes, we had to use wave guide as well.

Oh, one last thing: considering that FM is line of site and is very dependent on the surroundings, 60 mlles is quite a stretch for most antennas, even some "FM only" antennas

And finally, a big hunk of metal high up will trump a tiny piece of metal with a big amp any day.

 

[I LIKE MUSIC]

it's just a signal and some polished aluminum

This shows a lack of understanding of even basic antenna theory. Basic antenna theory tells us that the dimensions of the elements and the element spacing are determining factors in the performance of an antenna. And that is the point.

While just about any conductor stuck up in the air will capture some signal, there can be a very large difference in the amount of signal captured (delivered to the tuner/receiver). Again this is just antennas 101.

In weaker signal areas, that lack of signal is going to be an issue.

For sixty miles cheaply I'd find an old TV antenna

If in a given location a TV antenna delivers enough signal, that is great, and there are any number of people that use a TV antenna for FM broadcast band reception. But that does not mean that a TV antenna will be the best choice in all situations, especially in fringe reception areas. It is just this simple. Given the range of possible signal strengths encountered, from strong to very weak (fringe areas), recommending just any "old TV antenna" with out any additional information about the TV antenna is not the best advice.

What if the TV antenna chosen has 10 dB less gain than a dipole antenna over the FM broadcast band?
That would mean that it could deliver 16 dB less signal than a basic purpose designed FM broadcast antenna and that is a big difference. It is easily the difference between receiving the stations of interest and not receiving them,

It has nothing to do with the narrowness of definitions. It has to do with the design of the antenna. It is antennas 101. It is about making the best choice for a given situation.

And per your posts, how does a person looking at an old TV antenna on the roof of an old house know its performance for the FM band? That is my point. A person may try to use a TV antenna for FM reception, go to all of the work and expense of installing it only to find that it does not work as expected. It is just this simple.

 

[I LIKE MUSIC]

There is more for those that are interested. If you are not that is okay.

I just modeled a simple antenna in a basic antenna modeling software.

The first picture shows the reception pattern of a basic antenna. Maximum reception is in the X direction. This is the front of the antenna. This is the forward gain of the antenna. It is what is referenced in my first picture that shows the gain of various TV antenna for the FM band.



This picture shows the amount of signal that is supplied by each element of the antenna. Note X is the forward direction or the front of the antenna. This is a good thing.



This is a picture of the antenna when it is trying to receive a signal 5 MHz higher than it was designed for. Note the gain has decreased by about 10 dB. Not necessarily a good thing.

Also note that the direction of maximum sensitivity is now in the opposite direction.



Note in this picture the signal on the elements facing toward the front of the antenna (the X direction) has gone down to almost zero. Not a good thing for trying to receive stations in the forward direction of the antenna.



Note that I chose a 5 MHz higher frequency.

The end of the frequency for TV channel 6, the highest frequency for a VHF low band antenna or the VHF low band section of a combination TV antenna is about 87.5 MHz.

5 MHz higher is 92.5 MHz. This is where the first picture that I posted shows the FM gain of several TV antennas falling of the cliff. Again, this is just basic antennas 101.

With more complicated combination TV antennas with different designs the reception pattern can vary even more when the antenna is used outside its basic design. Note that the gain in the X direction, the front of the antenna has gone down by almost 15 dB. There is more gain at an angle of 45 degrees and off of the back of the antenna at 45 degrees.



If a person does not know the characteristics of the "old TV antenna" how do they decide what direction to point it for FM reception? Remember X is the front of the antenna.

And another thing. The feed point impedance of the antenna will change. There can be significant impedance mismatch losses in addition.

So it is much more than "just a signal and some polished aluminum". And making a blanket recommendation "For sixty miles cheaply I'd find an old TV antenna" is not going to be correct in all situations. If it works okay that is great, but it is easy to see that there is no guarantee (blanket recommendation). And depending on the TV antenna used, it may not work at all.

 

[Roumelio]

You could always get a cheap fm dipole for a few dollars or even a rabbit ears antenna. How well they work will depend on what stations you are trying to pick up distance wise.

Rabbit ears or even a loop antenna will work just fine. You will be able to grab a signal because FM works on the same frequency, or near enough to the old VHF. This is also why you got VHF interference when you were tuning your old analogue TVs. An old style VHF antenna on your roof top is a cheap solution also if you have one.

Other than that the suggestion to either buy or make a yagi aerial for FM is a suitable idea, but roof mounting may be either impossible pending what your allowed to do on your property, or cost prohibitive.

Start with the the older style indoor rabbit ears and go from there. You can investigate a directional yagi which you can point in the direction of your nearest tower starting from about $20 on ebay. If you have a roof top you can connect it to your existing radio/TV mast on your house then run a wire down off your roof top.

The other option is a non-directional dipole antenna which you can just put up anywhere you like but these will run you a bit more expensive again. At around $50, you won't need to work out what the polarisation is for your favourite radio stations in your area.

Depending on the age of your house you can try your house wall socket, but most digital TV antennas now are tuned for UHF band IV and V and wont likely do squat for radio today. I plugged my radio into the TV socket in my wall and got absolutely nothing out of it here in Australia.

 

[I LIKE MUSIC]

I guess there are those that will continue to ignore basic antenna theory and make blanket recommendations.

Saying that an antenna will work fine without knowing the power of the stations of interest and the distance to the stations of interest and the local conditions is just silly.

Of course a particular type of antenna may work okay or it may not depending on the signal strength of the stations of interest at the receiving antenna.

For some a 6 inch piece of wire will work okay, but others may need a massive FM only antenna high in the air.

The OP is trying to receive stations from 65 miles away. This could easily present a challenge for an indoor antenna and even some if not many TV antennas for the reasons that I have posted.

 

[Roumelio]

Excuse me but I didn't even see page 2 of this discussion before I posted. Either way if you're trying to receive a station from 60miles away it depends on a myriad of factors, signal broadcast strength, line of sight, etc, and on and on and on. You may not even get a signal depending on your topography. Without knowing any of that we can only make generalisations. Without a repeater station you would most likely need a very good external yagi or omni directional FM antenna and a large mast.

The which way to point it is simple enough in the days of the internet you can look that up for yourself, there will be an online radio community for your country/location which will tell you explicitly in black and white, that's not the hard part at all. Whether or not its going to work depends entirely on your topography.

In my case I've got a 150metre high mountain in my direct line of sight in the direction of all the major TV/Radio stations. Pretty much a stereotypical blackspot. This precludes me of getting anything beyond about 5km distance without a repeater. Thankfully everything I listen to or watch has a repeater station within radius that I can piggy back onto. I can't however under my own impetus connect to any wireless signal beyond that radius which means wireless internet and etc...

The first thing in all cases is to do some geo-maping, Google Earth should do the trick, to see whether what your even suggesting is feasible. Asking whether someone can access a radio station from 60miles away is a bit like asking how long a piece of string is. There are too many variables without first understanding the topography to even begin to answer the question.

 

[rcs16]

Haven't you seen any of the old triple stacked TV antennas on huge old two story houses that some old people have owned forever?

Make it easy for everyone and show a picture of what you are describing.
I LIKE MUSIC, thanks for all your information.

On the whole, most users were very satisfied with these combo units. Even me. I used it for both TV and FM and was happy as a seagull with a french fry.

I continue to use an outside deep fringe LPA with a amp on top of the 40 ft tower and the original 300 ohm balanced line (no cracks). It has to be 30+ years old or more, as shown above by I LIKE MUSIC. Since it is a directional antenna, a rotor in almost a necessity. You have to realize that atmospheric conditions change throughout the day and are also weather related, so adjusting the ant direction is helpful to get the best signal possible and reject the ones that interfere..

The first thing in all cases is to do some geo-maping, Google Earth should do the trick,

Forget all this unnecessary analysis, just use some basic logic, trial and error will win out every time.
Non-directional antennas are problematic and should only be used for strong carriers in close proximity, <~50 miles or so. Even then, they do a poor job of providing gain, rejecting interfering carriers.

 

[sixthday]

Bought many in estate sale for $1 or less

 

[Roumelio]

Forget all this unnecessary analysis, just use some basic logic, trial and error will win out every time.
Non-directional antennas are problematic and should only be used for strong carriers in close proximity, <~50 miles or so. Even then, they do a poor job of providing gain, rejecting interfering carriers.

Trial and error works until you've just burned $50 on an aerial to find out you can't get a signal anyway. Its' always best to start from point A and some basic understanding of your topography that your installing your mast in. This will tell you lots of things, including how high your mast should be in order to get clear line of sight.

It might be impossible as it is in my case. Even if you stick a mast on top of my roof you're gonna get about 30metres clearance off the ground which is going to get you dick all coverage when you have what amounts to a 150metre high Faraday cage in your direct line of sight. Then you realise you bought an aerial thats worthless.

 

[I LIKE MUSIC]

rcs16, you are welcome.

I am not trying to be the TV antenna police, although my super OCDness tends to (well even more than just tends to) have an impact on what I write. I am just sharing some basic antenna 101 theory and application.

Way, way back in the day, I installed RCA TV combination VHF low band/VHF high band antennas for certain applications. These antennas had some unusual lobs in their reception pattern like shown in my picture above. One of the lobes worked okay for the reception of the only UHF station and another lobe worked okay for the reception of the only FM station available at the time (it was rather difficult to receive using an indoor antenna).

It was just luck that the unintended lobes matched the directions needed for the UHF station and the FM station and there was enough RF field strength to make it work. So contrary to the impression that I may have given with my posts, I have used TV antennas for FM reception and non intended UHF TV reception.

It is all about the amount and quality of the RF (FM) signal as seen by the antenna. It can be no other way.

 

[I LIKE MUSIC]

Antenna trial and error.

Again way, way back in the day I used devices like this. Although this device was considered to be rather good for field work installing antennas, looking at the signal level at the antenna and at the TV end of the feed line, the first devices I used were considerably more crude and less accurate.

I still have one left in storage although it is from a different manufacturer and is a little more fancy.



One typically wanted a 0 dBµV signal level (1000 microvolts in this specific application, in normal engineering notation this would be 60 dBµ) at the TV end of the antenna feed line.

Providing the needed signal to 50 or 100 TVs from a single TV antenna on an apartment building is not the place for trial and error.

 

[I LIKE MUSIC]

Back on topic.

Ryan, have you tried any indoor antennas for your stations of interest and if so what are the results?

 

[sregor]

Some DIY discussions:
http://audiokarma.org/forums/index.php?threads/diy-fm-antenna.633879/
http://audiokarma.org/forums/index.php?threads/antennas.682313/

Also search J-pole

 

[rcs16]

including how high your mast should be in order to get clear line of sight.

You are never going to get a clear line of site unless you are in very close proximity of the transmitter. You are relying on the signal bending and curving around objects.

It might be impossible as it is in my case. Even if you stick a mast on top of my roof you're gonna get about 30metres clearance off the ground which is going to get you dick all coverage when you have what amounts to a 150metre high Faraday cage in your direct line of sight. Then you realise you bought an aerial thats worthless.

Also have to agree it maybe the case, so a $50 investment is not too bad of a loss for an possible unobtainable objective.

As "I LIKE Music" suggested, try by constructing a folded dipole tuned to the desired freq and see what you get.
http://cyberpoet.net/writes/web/infwiz/spant.html