EV's Best Top Rated FM and HD Radio Antenna Guide & Reviews

EscapeVelocity

Moderator, , Webmaster of EV's Antenna Blog
#21
This link is similar to the TVFool and FMFool....try it out.

AM FM Zip Code Based Signal Strengths


Here is another....with this one, you can also find unused frequencies on the FM Dial...hmmm! ;)

Radio-Locator.com

Welcome to Radio-Locator, the most comprehensive radio station search engine on the internet. We have links to over 10,000 radio station web pages and over 2500 audio streams from radio stations in the U.S. and around the world.
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Yes616

The Mod Squad
#22
Thanks Escape. Especially for that radio-locator link. It's pretty good and I have been doing my own little thing on and off thing running a 25 mW transmitter out of my basement so I can get everything I can get from my Yamaha audio / video receiver out to the back yard. The neighbors can hear my stuff too. :) The range is about 0.1 miles.

I have a FM radio out by the backyard swimming pool and it's a great way to get Sirrius radio out there.

There is no mention about the frequency I use at my location though. 89.7 MHz seems to be the best here but that doesn't show up at zip code 12754.

Maybe they are seeing me but have no idea what to make of me. LOL
 

Piggie

Super Moderator
#25
..... I have been doing my own little thing on and off thing running a 25 mW transmitter out of my basement .....

There is no mention about the frequency I use at my location though. 89.7 MHz seems to be the best here but that doesn't show up at zip code 12754.

Maybe they are seeing me but have no idea what to make of me. LOL
Be sure the alien cats know about your station. Actually they told me you could raise power by 6db be legal, because they need the power.
 

EscapeVelocity

Moderator, , Webmaster of EV's Antenna Blog
#28
Blurb on the internet...

Long distance reception of FM broadcast signals occurs in many different ways. Here's a look at the main propagation modes:

Sporadic E-skip (Es)

This signal propagation mode occurs when a FM signal strikes a highly ionized patch of the E layer of the atmosphere and the signal is reflected back down to Earth. As a general rule, Es will reflect a signal 500-1,500 miles. On rare occasions, Es "clouds" will line up to provide a double hop, producing reception of stations 2,000-3,000 miles away.

Es can come in with rapid fades, and you'll often find 2 or more stations fighting it out for control of the frequency. Often you'll have stations in as strong as any of your local stations, with full stereo. The stations you receive via E-skip will generally come from the same area, but beware...Es clouds tend to move around. For example, DXing from the Midwest,you might have a cloud move so that your opening starts out in the northeast and winds up in Florida over the course of several hours.

The best way to keep tabs on Es is to check your open TV channels between channels 2 and 6. These channels will be the first to be affected by Es, as they are lower in frequency than FM, which falls between channels 6 and 7. As the activity of the Es cloud increases, so will the chances of the opening moving on up to FM

What causes Es? There are several schools of thought on the issue. The radiation level of the sun and the chemical makeup of the atmosphere directly affect it. And current research shows that the electrical activity surrounding thunderstorms may have the most profound effect of all.

Tropo (Tr)

Tho a much more stable mode of propagation, tropospheric bending/ducting (Tr), for the most part, lacks the distance characteristics of Es. Openings by Tr can run from 200 to 1,000 miles, and sometimes even beyond.

Tropo is directly related to weather, with the influence of a high pressure area required for it to happen. With a temperature inversion, with warm air meeting cold, a low level conduit forms in the tropospheric layer of the atmosphere that causes FM signals to travel hundreds of miles. It's most likely in the morning and evening, with September and October often the best months. It's not unusual for tropo conditions to last for several days over a wide area.

Meteor Scatter (Ms)

This mode of propagation is often the most frustrating, as the signals are so short-lived. It can affect the entire FM band, but it's best to park on an open frequency and see what happens. Ms usually will bring in signals in the 200-1,200 mile range. Most meteors that enter Earth's atmosphere burn up, leaving a visible trail. FM signals reflect off this trail, giving DXers usually anywhere from 1-10 seconds of audio. Obviously, it requires a lot of patience! During the big meteor showers, like the Perseids in August, you'll hear several signal bursts each minute.

Auroral Scatter (Au)

FM signals can actually reflect off the aurora borealis, with catches possible in the 300-800 mile range (and sometimes beyond). It's far more likely to be accessible to northern DXers. If you hear about a solar flare or increased solar activity, be on the lookout for Au. Signals by this mode tend to be slightly distorted.
 

Piggie

Super Moderator
#30
Probably the weird propagation I have seen on VHF happened in 1989. The aurora was so strong you could actually see it here in North Florida. It was slightly visible as far south as Orlando. There was also a massive tropo opening that night. I was hearing 2 meter repeaters when I noticed it as far north as the Carolinas (146 MHz). Then I heard people taking about seeing the Aurora up there, I went outside and low and behold the northern half of my sky were blobs of color. Not the dancing fences you see but just like someone threw blobs of color on the sky.

I didn't have a 6m rig at the time but was talking to a guy I knew 25 east of me that was on the air talking up into Ohio and PA on tropo or something. The guys up north were hearing Canadians on Aurora skip (it has a weird echo sound). Then my buddy in Florida started hearing Candadians with that aurora sound, and exchanged call signs with several of them on 54 MHz.

But what is weird it was that one of the longest known Aurora openings? After all we could see the color blobs in Florida. Or was it tropo skip from Florida to the Ohio/Penn region then changed to Aurora for the rest of the trip into Canada?

We concluded it was not long Aurora skip. Because the stations in Ohio area didn't have the tell tale warble of Aurora skip, but the Canadian stations did. The guy in Florida that worked them recorded it and played it back to me over 146 MHz so I could hear it. Indeed it was most likely 2 part skip. And a LONGGGGGGGGGGG distance.

A few days later in the same tropo opening another guy I knew scored a contact from Florida to New Hampshire on 1296 MHz. Now that is a long long long skip for that band.

I have often said the hams need a 1 or 2 MHz of a band around 100 MHz or near the FM broadcast band.

Why? That band is at a frequency where you can experience just about every type of propagation. As the article above shows.
 

Don_M

DTVUSA Member
#31
Amplifiers, Traps, Filters, Diplexers, etc.

Winegard CA8800 FM Band Separator/Coupler



I've got one of these in my entertainment center. In systems where an FM receiver is part of the mix, a CA-8800 will strip video noise out of the signals for the radio receiver and act like an FM trap for the TV signals. In really strong FM-signal areas, this can be used in addition to an antenna-mounted FM trap for even greater attenuation. The FM output can be terminated if the TV antenna won't be used for FM reception. Its insertion loss is practically non-existent compared to that of a regular splitter. IMHO, a CA-8800 is a wise investment at a modest cost.
 

EscapeVelocity

Moderator, , Webmaster of EV's Antenna Blog
#32
Great tips Don! Yeah, its a great tool.

You can use it to integrate an FM antenna into the same line as your OTA TV antenna as well, but you need to mount it in a waterproof box(unless your antennas are in the attic)....then use another down the coax line to split it back out for your TV and FM tuners.
 
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Piggie

Super Moderator
#33
Something to add to my splitter joiner page, or lets say the splitter joiner page. any fame I get online will buy me a cup of coffee if I can buy it.

There are lots of interesting things to do with splitter joiners, from blocking a strong low band station. Using a low high band splitter for an FM trap. Use a subband joiner to filter a CB or Ham HF transmitter nearby.
 

EscapeVelocity

Moderator, , Webmaster of EV's Antenna Blog
#34
Fascinating...

It looks like the Terk and Parsec Obelisk Towers and the Terk Pi and Terk FM+ antenna elements and circuitry/amplifiers were designed by Larry Schotz! For those who dont know who Larry Schotz is, he is a legendary FM tuner genius! He designed FM noise reduction circuits for FM tuners that were used in Proton, NAD, and Nakamichi tuners, among others.

His current business: LS Research

In 1980 LS Research was founded by Larry Schotz, one of the premier RF engineers of FM receivers. Since that time, Larry Schotz has acquired numerous patents to his name. Some of his accomplishments include the first phase-lock-loop digitally tuned receiver, the Schotz noise reduction circuit, and the cassette adapter for portable CD players.
This vastly increases my enthusiasm for these units.


SOUND: Technology Trims The Rabbit Ear
By Hans Fantel
Published: Sunday, May 28, 1989
The New York Times

Early attempts to deal with this predicament were made by Terk and Parsec. Both companies came up with fairly inoffensive indoor antennas shaped like slender obelisks about 16 inches tall. This height seemed irreducible, since the effectiveness of the antenna depended on its length being a certain fraction of the median wavelength in the FM band. Such antennas worked excellently, but they still seemed esthetically obtrusive to many.

At this point, Neil Terk, a well-known industrial designer and president of Terk Technologies Corporation of New Rochelle, N.Y., sought the advice of Larry Schotz, a consulting radio engineer with several important inventions to his credit. Among his achievements are the ultrasensitive, distortion-rejecting FM circuits used by Proton and NAD in their tuners and receivers Mr. Schotz managed to shrink the outer dimensions of the antenna by a new configuration in which its necessary total length is folded on itself somewhat like a pretzel. Technically this is known as a gamma loop and allows the antenna, which is still 16 inches long, to be coiled into a thin round disk of only 5 1/4 inches in diameter - about the size of a CD. Being so small, this disk is easily tucked away behind or among the other audio components and thus can remain wholly out of sight. That took care of the esthetic problem.

However, a technical problem remained. Compactness could be achieved only at the cost of lessened sensitivity. To make up for this, Mr. Schotz inserted an internal amplifier into his tiny antenna to boost weak signals, as he had done in the earlier obelisk model. Yet conventional amplifying circuits would not do for this even more critical job, because they introduce a slight amount of background noise. Though this noise is merely marginal at its source in the antenna, it is increased by every subsequent stage of amplification along with the signal itself. By the time the signal reaches the loudspeaker, the noise is no longer negligible but audibly encumbers the music.

Eventually, Mr. Schotz surmounted this obstacle through the use of an exceptionally noise-free type of transistor, made with gallium arsenide as its active element. The net result was a tiny indoor antenna with surprising pulling power. Called the Terk ''pi'' - after the Greek letter that figures in the geometry of circles - it far surpasses the performance of those egregious rabbit ears.

As with any other antenna, the effectiveness of the Terk pi, which carries a list price of $80, depends on the distance of the transmitter to be received, the character of the intervening terrain and the height of the receiving location above the average ground level of the area. When these conditions are favorable, the Terk pi, in conjunction with a good FM tuner or receiver, can bring in stations from as far away as about 50 miles. By the same token, the surprising pulling power of this antenna is not really needed in places close to the station. In most urban locations, for example, local FM stations come in so strongly that the antenna's sensitivity is quite unnecessary.

For this reason, Terk has recently developed a simpler version of its compact antenna without the built-in amplifier. Called the FM+, its outer shape is a thin five-inch square, but its internal structure preserves the space-saving pretzel principle. Its price, thanks to the absence of the costly internal amplifier, is a modest $19.95, and many listeners may consider this a cheap way to get rid of the rabbit.

Both the Terk pi and the FM+ can be used in two ways: Lying down flat, they are sensitive to signals from all directions. When set up vertically on their small integral stands, they may be oriented to favor signals from a particular direction.

This directional response may also be used to suppress multipath distortion, which occurs when unwanted signal reflections from tall buildings or other structures are received along with the main signal. Orienting the antenna toward the main signal source (and away from the reflecting structure) often resolves the problem. It should be noted, however, that both Terk antennas are strictly for FM. They will not work for television.

SOUND: Indoor Antennas Challenge Rooftops
By Hans Fantel
Published: Sunday, August 28, 1988
The New York Times

The alternative of indoor antennas used to be unsatisfactory. Even the best weren't very good, and their scraggly rabbit-ear wire loops were hardly an asset to domestic decor. Far better indoor antennas have recently been produced by Terk Technologies of New Rochelle, N.Y., and Parsec of Wilmington, Del. Both firms offer models based on ideas of Larry Schotz, a young inventor who enjoys the reputation of a wizard among radio engineers, and each antenna has the added advantage of a pleasing and unobtrusive appearance.

Terk's new model - the one picked by MOMA - is called ''pi,'' after the Greek letter forever associated in the minds of geometry students with the circumference of a circle. The name is apt, for the antenna takes the form of a small disk, five inches in diameter and one inch thick. Angling this disk so that its flat side faces in the direction of the transmitter can greatly reduce multipath distortion. Available in gray or white, Terk's pi ($80) fits discreetly into almost any domestic setting.

So does Parsec's equally handsome LS-4 ($60), a slender, slanting column, dark gray and 17 inches high. Its circuits include a new type of transistor that employs gallium arsenide in place of the customary silicon, making its sensitivity the highest among models currently available.

In a test recently conducted by an independent laboratory in Great Neck, Long Island, the Parsec pulled in 38 stations under the most difficult conditions, being positioned in a ground-floor room. By comparison, a large roof antenna advantageously positioned 30 feet higher pulled in 50 stations. The difference is smaller than one would expect, attesting to the new indoor antenna's effectiveness.

When used in upright position, the Parsec accepts signals from all directions. If laid flat, it becomes directional and can be aimed at specific stations. In that mode, it also blocks disturbing multipath reflections.

Both the Terk and the Parsec antennas have internal amplifying circuits and must be plugged into an electrical outlet. They form the vanguard of a new kind of indoor antenna design that challenges the monopoly of rooftops on good FM reception.
 
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Piggie

Super Moderator
#40
One thing about that article that kind of surprised me is what a few on the forum here have been mentioning all along. Powered (active) indoor antennas do not receive signals any better than (passive) non powered antennas. Funny also that the DIY 300 OHM antenna outperformed the factory built indoor antennas.
Amps, overload and noise floors have been known for almost a century since the first tube receivers were built. So it's very old knowledge.

It's all about "wireless" being rediscovered. Typical for everything in life and history of something being "rediscovered". There are always those during the rediscovery process that ignore old data simply calling it old and saying this is today and past knowledge is irrelevant since it's now the future.

I simply call it not knowing or learning from history.

I can tell from things posted here from time to time, regardless of how many times I say that an amp DOES NOT boost the signal making the antenna perform better, someone eludes back to the fact amp increases gain. Hog wash!

It's a mindset of being bombarded by incorrect information, and misunderstanding. Granted the difference between antenna gain and preamp gain and what it accomplishes seems elusive. Then add noise figure into that and it seems to loose even more.

I hear it all the time that an amp has to help because the reception is better. Sure, since most modern amps have a lower noise figure than the receiver itself.

I guess I need to get off my pork loins and write the article I keep putting off.

A 300 ohm twin lead antenna for VHF put up high on a wall behind the TV can out perform rabbit ears and easily hidden behind a picture if needed. I submit also it's better to put the balun as close as possible to the twin lead folded dipole as possible
 

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