Omnidirectional Indoor Antenna Boosts Fm Reception

May 03, 1985|By Hans Fantel. New York Times News Service.

It is an old and not entirely facetious maxim among audio fans that the most important part of an FM tuner is the antenna to which it is attached. It is also a maxim mostly ignored.

Too often an otherwise capable tuner or receiver is hamstrung by a grossly inadequate antenna. In fact, if the stereo systems seen around this town are typical--and I suspect they are--most antennas used by apartment dwellers are grossly inadequate. Things are better in the suburbs or the more distant boondocks where marginal receiving conditions force listeners to give their tuners a fair shake by putting a reasonable antenna up on the roof.

But most city dwellers have never seen their roof and wouldn`t know how to get there, and not all of them benefit from the master antennas supplied in some of the larger apartment buildings. Besides, some of these master antennas work only for television and deliberately cut out the FM band. So those city folk--faute de mieux--just let a piece of wire dangle from the antenna terminal of their tuners and then complain that the sound is fuzzy.

A minimal antenna of sorts is usually supplied with new tuners and receivers, consisting of flat twin-lead wire arranged in the shape of a ``T.`` To work even moderately well, this antenna must be spread out so that the top bar of the T is straight horizontal. To achieve this, the antenna must be tacked to the wall or the back of some furniture. Some listeners don`t bother to do even that. They just stuff the wires behind the receiver, and the mushy sound they get is their reward.

An additional requirement for optimal operation is that the T-bar of the antenna must be perpendicular to an imaginary line drawn from your house to the transmitter. But the wall or the furniture to which the antenna is tacked may just happen not to be oriented the right way. Besides, you may want to listen to more than one station and its transmitters may be situated in different directions from your house. Right away you run into trouble and damaging compromise.

This is just one reason why these floppy soft-wire antennas furnished with tuners and receivers should be used only provisionally until a more suitable antenna is installed. Many urbanites, however, never replace the provisional antenna. By sheer inaction, they live with it unhappily everafter. A simple and effective remedy for this common condition comes from Italy in the form of a technially sophisticated and visually attractive indoor antenna imported by Parsec Electronics of New York City. Unlike those scraggly ``rabbit-ear`` contraptions that people with a rudimentary sense of decor would banish from their home, the Parsec`s appearance is agreeably discreet. It is a square black rod, 16 inches high and tapered at the top. Standing on a base about the size of a small wallet, it takes up virtually no space, can be readily hidden and even when in full sight blends nicely with contemporary furnishings.

Inside this slender, slanting obelisk is a tiny amplifier that boosts the incoming signal by as much as 24 decibels, thereby giving this device an effectiveness comparable to that of a much larger antenna. To provide power for the built-in amplifier, the antenna must be plugged into an electric outlet--preferably one at the rear of the receiver so that it turns on and off along with the rest of the system.

What sets the Parsec (Model 7403) apart from other indoor antennas (and most roof antennas) is that it is omnidirectional, accepting signals from all directions with equal alacrity. Consequently, there is no need to reorient the antenna to receive stations from different locations. Anyone who ever fussed with rabbit-ear antennas trying to position them at just the right angle to catch a particular station will appreciate this utterly fuss-less design.

The Parsec`s omnidirectional pattern seems especially effective in high-rise neighborhoods. For example, amid New York`s predominantly vertical architecture, radio signals are often unable to reach the depths of the city`s concrete canyons. The steel frames of skyscrapers tangle with the airborne music or partly siphon it into the ground, erratically weakening the strength of the airwaves in certain spots. Poor reception, fading signals and fuzzy sound are thus added to Manhattan`s many tribulations.

While the omnidirectional antenna cannot in itself reject spurious signal reflections from the steel shell of tall buildings, it can--by not favoring signals from any particular direction--often ameliorate deleterious effects. The result depends on the particular pattern of signal reflections impinging on a particular location, but in many cases this antenna will do a good deal better than conventional indoor antennas. Moreover, the Parsec`s internal amplifier is adjustable so that the signal obtained is neither so weak as to suffer from background noise, nor so strong as to overload the tuner and cause distortion.

For good measure, this reviewer has also tested the Parsec in atypical situations in a remote rural area. Laying the antenna on its side makes it highly directional so that it can be aimed at a weak and distant station to be pulled in. Thanks to its internal amplifier, the Parsec also proved quite effective in this type of application, though it should not be regarded as a substitute for a roof antenna for long-distance FM reception. Considering the improvement it is likely to bring in many situations, this ingenious gadget seems well worth its $70 price.