Anyone found an antenna amplifier that improves reception?

[Mike Walker]

When I first got my HD Radio, I found out quickly that amplified antennas such as those from Terk are a no-no.

But I was wondering if anyone here has found an in-line antenna amplifier that actually improves (FM HD) reception (instead of destroying it! I read somewhere (I forget where) that someone successfully used an old Channel Master, and began getting stations from like 110 miles away in HD, rather than 50 or 60. I have no personal knowledge of this at all, but do have a couple 'o antenna amps in drawers somewhere. Anybody got any experience in this area?

 

[clouseau]

.... Anybody got any experience in this area?

The short answer is (for me) I have experience and NO I haven't found a good RF amp that really works well for reception. Most I have ud=sed take an "in the grass" barely detectable signal and make it a good strong, "In the grass signal."

Rarely has an RF amp helped receptin for me...

(YMMV)

Clouseau

Can someone help here?

 

[calstymes]

clouseau asked (in another thread):

I really don't think AM HD is the answer.

You don't think so?

And in this thread, he reported and also queried:

I haven't found a good RF amp that really works well for reception. Most I have used take an "in the grass" barely detectable signal and make it a good strong, "In the grass signal."

Rarely has an RF amp helped reception for me...

Can someone help here?

The OFF button has always worked for me.

 

[rbrucecarter5]

But I was wondering if anyone here has found an in-line antenna amplifier that actually improves (FM HD) reception (instead of destroying it! I read somewhere (I forget where) that someone successfully used an old Channel Master, and began getting stations from like 110 miles away in HD, rather than 50 or 60. I have no personal knowledge of this at all, but do have a couple 'o antenna amps in drawers somewhere. Anybody got any experience in this area?

The concensus from the folks over at fmtunerinfo.com and its companion Yahoo forum is that these signal amplifiers are a waste of money. The cheap transistors they use add more noise than they eliminate. NOTHING will beat the low noise front end of most top of the line tuners. Now if you are talking about the trendy HD radio table top radios, I doubt there is over $30 or $40 of electronic components actually in the box, based on sales prices of around $200. The mark up is the prestige of the trendy name. But the point is - there is no way those HD radios will include a $100 low noise FET in the front end. So there is a chance, somewhere, somehow, somebody got an in-line amplifier with a transistor that is statistically quieter than the radio's front end. So it might have helped.

The advice from someone who has done FM DX for 35 years, up to 350 miles, is: go with the best antenna you can afford. You drop $200 for a radio to get the best sound, you might consider $200 for an APS-13 deep fringe FM antenna. It is huge, but nothing will drag out signals better. Whether it is HD radio or not, you want to couple the maximum signal from the distant station into your radio / tuner. If you are talking about 110 miles, you are well over the event horizon. Those sidebands are broadcast at comparatively little power, and I would throw the very best antenna into the mix. An antenna / tuner combo that is capable of 300 mile reception might only get HD for 100 miles, so don't take chances with less than the best antenna. Don't forget low loss lead-in wire and lightning suppressors! And don't put an antenna up near power lines!

 

[Chuck]

A major problem with using wide band antenna amplifiers becomes apparent if you have a variety of signal strengths to deal with. That is pretty normal for most of us. There are usually a few local signals that come booming in. The strongest signal in your area will determine how much gain you can get before the amplifier overloads. Most consumer grade amplifiers (even the expensive ones) do not have the headroom to cope with this situation. Because they are typically broad-banded, this problem is magnified if you happen to live fairly close to a radio or TV station. Once the amplifier overloads, it causes way more problems than it solves.

Amplifiers can be very useful for distribution purposed (to multiple receivers) but they are rarely operated at much more than unity gain. The real reason for those amplifiers is to make up for the loss in the signal splitting process, not to increase receiver sensitivity. That's a big difference.

The best bet is usually a high quality antenna and good low loss feed line.

 

[Mike Walker]

There is ONE HD station I wish to receive that I don't currently with any regularity...WFAE Charlotte (90.7). An outdoor antenna will probably do the job, as I receive their analog signal very well. I can't get an outdoor antenna and rotor until spring or summer. Since I'm legally blind, i don't do ladders! I'll have to hire someone to put it up. The last one on my roof...Channel Master TV/FM antenna...lasted probably 30 years (I say "probably" because it had been up for years when I bought the house in 1986). I'm 48. If the next one lasts as long, it may well outlast me.

 

[R.F. Burns]

You might want to try a antenna pre amp available from Radio Shack. It can add gain and I use it with HD and have no troubles receiving all HD signals.

 

[Mike Walker]

Which one have you had success with (antenna preamp from Radio Shack). They don't just carry "one". They carry many!

 

[700WLW]

Which one have you had success with (antenna preamp from Radio Shack). They don't just carry "one". They carry many!

Gosh, all of our analog AM/FM radios do not need external antennas - hmmmm... have you tried mounting a roof-top, or attic antenna ?

 

[Chuck]

Which one have you had success with (antenna preamp from Radio Shack). They don't just carry "one". They carry many!

Radio Shack sell a mast mounted antenna amplifier that occasionally makes things better than worse. It is a two piece unit. The pre amp installs at the antenna, the power supply is located inside your house on the receiver end of the coax. The good news is the power supply module has a gain control on it, which allows you to get as much gain as possible without overloading it. Unfortunately, you indicated that you don't have an outside antenna, so it will be of little interest to you at this point.

I think they do have a stand alone indoor 10 db amplifier with a gain control on it. You might give it a try. Be sure to save all your packing materials so you can return it if it does not help. As I tried to explain earlier, these things sometimes make things worse, rather than better. If you had a BA Receptor, it would probably help. The Accurian on the other hand seems to have a very sensitive front end, and any amplifier may make the situation worse.


Have you considered an antenna in your attic? If you can find Radio Shack's 6 element FM Yagi at your local store, it is a good antenna for under $25.00. Unfortunately, they discontinued it just as HD rolled out. Perfect timing...

 

[R.F. Burns]

Which one have you had success with (antenna preamp from Radio Shack). They don't just carry "one". They carry many!

Sorry for the delay. What I use is the mast mounted pre-amp, with the FM trap out. My setup is unusual for a pre-amp in that the power supply is mounted maybe 5 feet from the pre-amp itself and the pre-amp is connected directly to the antenna. In this case it acts more like an amplifier located at the antenna rather than one which amplifies the signal after it's passed through 100 Ft of cable. It has no negative effect on the HD signal and with it I am hearing stations which I otherwise can not hear without it connected. I agree with others who recommend attic mounting your antenna. You can by a radio shack TV antenna and put it in your attic (if you have one) and with the pre-amp you will be very happy. If you can put up a rotator as well all the better.

 

[hipporadio]

What I use is the mast mounted pre-amp, with the FM trap out. My setup is unusual for a pre-amp in that the power supply is mounted maybe 5 feet from the pre-amp itself and the pre-amp is connected directly to the antenna. In this case it acts more like an amplifier located at the antenna rather than one which amplifies the signal after it's passed through 100 Ft of cable.

The key is to find a pre-amp that you can operate with the FM trap disabled and NOT experience overload from a local FM station. I went thru this ritual back in the 80s in a location where 40 to 50-foot residential towers were common to view distant TV reception. A problem surfaced from the 28kw local FM a few miles away—overloading the mast-mounted Channel Master amp, and messing up the FM band—even on a very able McIntosh MR-78 tuner. The FM overload also caused serious interference to VHF channels 2, 4, and 11. Luckily, I was “tight” with the antenna guy, who suggested a commercial-grade amp from Jerrold (a company specializing in CATV/CCTV gear). The price for the amp doubled—but the problem disappeared.

I’m unfamiliar with Jerrold’s life (if it even has one) today. Possibly, you could find one in good used shape. Certainly there is a contemporary commercial equivalent, but my enjoyment of most FM has passed—so I must admit to falling behind on these over-the-air matters. I can emphatically state that I have had NO positive experiences with amp products available at today’s Radio Shack [very sad]. Even the amplified Terk compact outdoor/attic dipoles have been a disappointment for FM.

 

[Tom Wells]

I use a mid-80's winegard max fringe yagi w/rotor in the attic, 70 ft of coax to basement, and then a 1980's RS FM amp.
I added a true bypass/cutout switch, for use when the amp is off.
It's connected to a Sansui TU-7700, which has a built-in front-switchable FM antenna pad.
I live 7 miles from downtown Chicago, and normally leave the FM amp on, and the antenna loss pad switched in.
Most of the time this combination is better than amp off and pad off.
It all depends on overload. Seldom do I find better reception from antenna/no amp/no pad.
If I were any closer to downtown, I expect I could not use the amp at all.
Anyone in the boonies ought to try an amp, but I when I was 45 miles from Chicago, I found I needed the amp, but
absolutely had to add the bypass switch, as many stations sounded better with the amp out.
Turning the amp off made for a much noiser signal than no amp in-line.

 

[R.F. Burns]

What I like about the Radio Shack preamp is that is that there's a pot on the power supply end so that you can adjust the amount of gain so that you don't overload your receiver.

 

[rbrucecarter5]

Anyone in the boonies ought to try an amp, but I when I was 45 miles from Chicago, I found I needed the amp, but

An amp was no good for me. In the late 1970's I used a Radio Shack ten element double driven Yagi on a 40 foot mast, driving shielded balanced 300 ohm lead-in to a Heathkit AJ-15. I was in the very definition of "boonies" - Midland, TX listening to Dallas FM over 300 miles away. Reception was reliable except when planes few into the airport a few miles away. Signal strength did not even make my meter move, but I got acceptable stereo quieting.

The one time I added a pre-amp to the setup at the antenna, it increased noise - not decreased it. The front end in the tuner was so quiet that an amplifier only added to noise.

One way to tell if your tuner has a quiet front end is to terminate the antenna input into a dummy load, measure the noise. Then hook up an antenna on a blank frequency and measure the noise. If you get less noise with the dummy load on your tuner, your front end is good. VERY few tuners have a front end quiet enough to notice a difference. Noise sums by the root sum square method, so the biggest contributer quickly overcomes the background. And the tuner itself is frequently the biggest contributer. Unless you make the mistake of adding an amplifier to the front end of a high-end tuner. Then the external amp becomes dominant.

When DX'ers have to tell HD enthusiasts how to REALLY receive HD stations, we are vindicated. There are not many listeners who have ever successfully sustained 300 mile plus FM reception - I am one. I don't know how that translates to HD range, but do everything right and you will have a shot at DX'ing HD from the boonies. I doubt 300 miles, though, given the power levels transmitted in the sidebands and the probability of adjacents on top of those sidebands. 45 miles? Should be a piece of cake with a decent antenna. I'm 70 miles from "local" stations and they blast in. No doubt HD would work, too - if somebody actually made a high end HD tuner (which is unlikely these days).

 

[hipporadio]

One has been found—but are you firmly seated?

I’m well-acquainted with a guy who is taking on his family’s farm in far northwest Missouri. Kansas City—2 hours south... Omaha—an hour-and-a-half north. It’s the land of tall residential TV towers. Over the years, sat dishes delivering DirecTV and agricultural commodity information have been displacing these structures. My friend enjoys his father’s mid-70s vintage Pioneer SX-series stereo receiver to enjoy distant Omaha, Lincoln, and KC radio. He’s in his low-30s and can still find relevance on the FM band.

Last August, a very powerful storm front passed—the same one that would later take out a tower in the 550 KTRS St Louis DA... Not before it toppled the tower on the farm. Since local television was now provided by DirecTV, there was little need to rebuild. A college fraternity brother in the upscale home audio biz in Omaha recommended an FM solution.

Magnum Dynalab is one of a very few remaining FM-centric audio manufacturers, and they offer a very good FM amplifier—the “Signal Sleuth M-D”. It is intended to sit at ground-level—actually mere inches from the FM receiver. It is very finely crafted (as is every Dynalab product), and offers DYNAMIC RF amplification and signal attenuation plus band-filtering and interference detection/limiting functions. I would normally question this units attempt to “defy gravity”—but allegedly it functions admirably with an outdoor Terk encased FM dipole (amp defeated) and mounted at roof-peak.

Now the reason you need to be firmly seated... The price—nearly $400

Cheaper than a new 50-foot tower/antenna installation, but is it worth it for FM’s rap, sap, and (well—you know)?

 

[Mike Walker]

Yeah Hippo, I've looked longingly at that Magnum Dynalab amp. But geez...I could buy two very nice tuners for the price of that amplifier. Or a superb antenna and rotor (plus installation). It's tempting, however (in the same way McIntosh components are tempting to old audio nerds like me! As they say here in North Carolina "it sure is purdy!")

 

[hipporadio]

Yeah Hippo, I've looked longingly at that Magnum Dynalab amp. But geez...I could buy two very nice tuners for the price of that amplifier. Or a superb antenna and rotor (plus installation). It's tempting, however (in the same way McIntosh components are tempting to old audio nerds like me! As they say here in North Carolina "it sure is purdy!")

I have no personal experience with this M-D product, and I have not seen the installation. The last time I visited to enjoy a ride on his combine, the tower was standing and delivered AWESOME FM reception.

Magnum-Dynalab is a very fine company, and I’d wager that they’d not hatch a product like this unless the benefits justified the cost.

The dealer (who I know very well) describes it as a “tuner before the tuner”. In addition to fully adjustable post-stage gain, there is pre-stage variable attenuation and RF level limiting coupled to a variable bandwidth filter. The unit is described as nearly impossible for a strong “local” to overload—that is the primary problem with most signal amps... “Big Bertha” hits the amp's front-end... Swamps the deck creating a mess which is later distributed for re-amplification by the tuners circuitry. End result is an inter-modulated mess.

M-D supposedly provides a very stern warning that this product NOT be used with an indoor proximity antenna such as a wire dipole or “pigtail” behind the entertainment center (for very obvious reasons). It needs to be fed via shielded coax from an element well away from any indoor RF trash. ‘Might be interesting to try out, but outside a “picky” subdivision—a trip to the corner outdoor antenna store may be advisable.

 

[Mike Walker]

I'd love to try it with one of Magnum Dynalab's tuners. Especially if you're buyin', Hippo