I was hoping to improve reception on a few stations , so I decided to replace the twin lead dipole (passive) antenna that came with my new tuner with the Terk Tower. I have the AM Advantage loop and that works fairly well, so I figured this powered antenna would be a lot better.
Well, bad reasoning. On FM, it doesn't work NEARLY as well as a 32" piece of plain old wire on any of my radio recievers.In some cases, stations that could be tuned reasonably well with *nothing at all* attached to the FM inputs, and no internal antenna, could no longer be received with the Terk Tower attached.
Those that could be tuned with the antenna attached had grotesque distortion. This despite turning the gain adjustment dial in either direction. It was functioning, as at low levels of gain, the station dropped off completely, and definitely changed as you moved it. So it wasn't just broken. I could get barely acceptable reception on a few stations with micro-fine adjustments of the dial. But even at best all stations had all sorts of fuzz and dropouts. You could turn it up enough to swamp the receiver ACG circuit, but the distortion never goes away as you turn it down the point of losing lock completely.
On AM, it doesn't make it worse, but it doesn't help, either. On all the weak stations I have tried, I simply can't tell the difference in the results. Once again, fiddling with the gain control changes it, but at maximum boost, it's pretty much what I was getting with the the teeny little loop antenna that bolts to the back of the tuner. At lower gain settings you just can't hear the station at all.
For all intents and purposes, it just doesn't seem to work,I tried it on 4 different tuners/radios in 4 different places in my house, and in every case it made the FM reception MUCH worse than the stock antennas, and AM reception no better than the stock or internal antennas. I'm probably going to break it open and try attaching different lengths of wire in place of the stock antenna, and see if that helps. But I get the impression that the booster amplifer just isn't up to the task of passing 107.7 MHz., and introduces too much distortion at FM freqencies. It almost has to be - because a plain old wire that length is MUCH better.
Even though it was pretty inexpensive, I was very disappointed with this antenna. You'll get FAR better reception with a bent coat hanger. And that's free with your dry cleaning.
(addendum - I finally broke my antenna open, and now it's clear why it doesn't work on AM any better than a stock antenna. It's because inside the tower, for AM, is a small, unamplified, loop antenna! It's not even connected to the circuitry. Which begs the question of why turning the dial affects the AM performance. I speculate that the AM loop and the FM amplifier are interfering with each other - and that the AM is getting into the FM amp, causing modulation at the FM subcarrier frequency, hence, really fuzzy FM reception - and also dragging energy out of the AM loop more or less depending on the FM amp setting. BTW, the FM antenna is a piece of bare copper wire running the length of the antenna. Short answer is still the same - it's junk, don't waste your money)
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Terk AF-9330 AM/FM Indoor Amplified Tower AntennaProduct Description: One of the world's most popular and recognizable antennas, AM/FM Tower (AF-9330) features a built-in amplifier that can be adjusted to the optimum level to strengthen weaker or distant stations, without over-boosting stronger or closer stations. The high-performance, high value AM/FM Tower is actually two antennas in one - it can function either as an omnidirectional antenna for great reception from all directions, or as a directional antenna to zero in on distant or weak stations.Exclusive Air Coil technology isolates AM and FM antenna elements from each other for increased selectivity with greatly reduced static and noise. AM/FM Tower features a non-skid base, which keeps antenna in place during adjustment.
Buy cheap Terk AF-9330 AM/FM Indoor Amplified Tower Antenna now
This inexpensive devise greatly improve my FM radio reception of numerous stations, and is definitely recommended.
I live in an area with very poor AM reception. My home is located in the mountains west of Denver. And for years from time to time I have tried every external AM antenna available and several different types of AM radios with no good results. The antennas included all of the TERK'sand CC Crane'sferrite loops both active and passive, dipoles, "long wire" antennas used by HAMS and a variety of active antennas with built in amplifiers with nogood results . My problem seems to stem from local inference radiated by my household and neighbor's AC wiring (noise from florescent lamps, computers, LANs, plasma TV's, motors, and light dimmers, etc) and generally weak AM signals shielded by the local terrain. My home does not have any line- of- sight to the AM transmitters I'm trying to receive from Denver 50 miles away. 
I bought the Terk antenna in an attempt to pick up some AM and FM radio stations I was struggling with on my new bookshelf stereo system.Perhpas because of my apartment building, or the quality of the stereo, the antenna didn't offer me much success in picking up stations any better than the factory-provided antenna.I did notice improvement in the static (or lack of it) on stations that were already tuning in fairly well (they went from great to excellent), but the stations that were tuning in "poorly" got no better with the Terk antenna.Overall, it was probably not worth the money paid.
There is an amplifier at the outside end of this cable.The compartment totally filled up with water after a few rain storms.I get no signal at all because of water damage.I had the connector oriented correctly accourding to the instructions, but it still filled with water.The lid eventually fell off...
I'm a stickler for performance, and have high expectations for electronic equipment... especially when I hear fellow users raving about a certain product. 
When I replaced my old analog FM tuner with a new one that receives HD, I was not satisfied with the signal strength and quality that I was getting from HD via my indoor dipole antenna.It was time for me to upgrade and this was the solution.
Ihave a Yamaha HTR-5750 receiver which I was using with a Radio Shack FM amplified antenna.I had tried various ways of improving my FM reception including the classic 300 ohm twin lead folded dipole antenna.The rabbit ear setup helped but still did not yield satisfactory results.I still had difficulties receiving some nearby FM stations that were considered moderate strength stations.
I bought a wonderful Grundig s35 radio, which works wonderfully in my Los Angeles home, but which suffers in performance at work, a college, because of so much interference in the building. I bought the Terk antenna to see if I could get KPCC, a Pasadena station about thirty miles away. The Terk succeeded. Whereas without the Terk antenna I could barely get KPCC, about 10% clarity, with the antenna this often tough-to-get FM station now comes in with over 90% clarity. Also all the other stations, both FM and AM, are now much stronger and clearer. So I'm glad I bought the Terk. Finally, let me add that the hook up is easy. You just snap the attachment to the back of the radio. Finished.
This antenna is designed to be a step-up from the wire antenna that likely came with your system. I use this in a high rise apartment with a steel frame, which wrecks havoc on FM signals. The Terk FM+ does not pull in stations from miles away that you normally wouldn't receive, but local stations that I previously had difficulty keeping static-free now come in crystal clear. If you're looking for an improvement to stations that are within range but need a little improvement, this product is for you.