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the Manufacturer of Select-A-Tenna Products since 1971

Model 541

Model 541-M

Model 541-S

    The Model 541 is a passive device that requires no wires, no batteries, no plugs, etc.  It works by simply placing it next to your radio and tuning the knob to the same station frequency as your radio.
       (See illustration below)

    The Select-A-Tenna functions by concentrating the radio station signal energy in the near proximity of the 541. If your radio has an internal antenna and is placed in that same near proximity, it shares the same signal concentration and gain improvement.

    While the +30dB signal gain improvement from the Select-A-Tenna is underway the radio's automatic gain control will also reduce the signal above a threshold level. The net effect is to make very weak signals +30dB stronger and yet have no perceivable effect on already strong station signals along with everything in between exceedingly improved.

   Someone once said, "Imitation is the sincerest form of flattery."  Recently, others have attempted to imitate this product. Their gain performance does not approach that of the 541.  It is -3dB to -9dB lower over the AM Band. If you want the best, buy the real thing!

   These products are manufactured in the USA of quality components and processes to provide you a lifetime of AM radio listening pleasure.

    This is the second generation of Select-A-Tenna.  It has the same intrinsic +30dB signal strength improvement and features as the basic 541 model.  In addition, a jack on the front panel allows the unit to be connected to either an outside long wire and ground, or as an alternative,  directly connected to a radio's antenna and ground terminals when the radio has no internal ferrite rod antenna.

    Users in all-metal buildings or campers, where AM radio signals do not suitably penetrate, find this unit effective because a long wire outside antenna and ground may easily be connected to the 541-M. This allows the good outside signals to be ported through the 541-M which is then placed next to the radio, for operation just like the 541 model.

    Other users with radios having only antenna jack and ground terminals, but who want an alternative to the long wire and ground, can connect the 541-M directly to the radio using the External Antenna and Ground Cable Assembly provided.

          (Typical radio connection)
    

The External Antenna and Ground Cable Assembly is illustrated below.

    This is the latest addition to the Select-A-Tenna product line. It was developed for radio applications like the B-W-R illustrated below. These applications have internal ferrite rod antennas that are more difficult than the average radio to obtain good High-Q mutual coupling with the Model 541or 541-M. The 541-S is the only uint we recommend for this application.
   (See application illustration below)

    The 541-S is an active device with additional controls that has an internal regenerative amplifier  and requires a 9V battery (Not included). The unit has an additional variable 0dB to +10dB gain added to the intrinsic +30dB for a useful gain up to +40dB. The unit has both Coarse and Fine Tuning controls for ease of operation at the higher gain settings. It also has the capability to effectively drive a remote ferrite probe. This is useful on applications of large case radio installations that the 541-S cannot access directly with it's intrinsic near proximity effect.

    The 541-S may be used in any of four different modes: 
(1) Direct Near Proximity just like the
     541 and 541-M. 
(2) Ferrite Probe Near Proximity. 
(3) Direct Wired Antenna Connection.
(4) External Antenna and Ground for
     metal-buildings when using
     modes 1 and 2.

    The 541-S has a high-signal level and low-impedance balanced drive port for the ferrite probe. This provides the capability to not only drive the 6 ft. coaxial cable and probe, which are included, but the cable may be extended to as much as 26 ft using extension cables readily available locally.  This is very useful for remotely locating the 541-S away from radio noise sources or into better signal locations, when moving the radio itself may be inconvenient.

Model 541 $59.95 

Model 541-M  $69.95 

Model 541-S  $189.95

Intensitronics Corp