ANTENNAS AND ACCESSORIES FOR PORTABLES
Many shortwave listeners use portable receivers. Most portables are designed to work with the built-in telescopic whip antenna. That's fine for the reception of strong stations, but not suited for serious shortwave listening. A larger antenna can give better reception, but connecting such an antenna to the external antenna input of the portable results often in strong noises, whistles and "ghost signals". Reason is overload. Portables are made very sensitive, because the efficiency of the whip antenna is very poor thanks to the lack of a counterpoise. Thanks to this high sensitivity the receiver cannot handle the much stronger signals of the larger antenna, resulting in mostly an even worse reception than with the whip antenna.
A large antenna on every portable
To solve this problem, RF Systems has developed the AA - 1 antenna adapter. This is a special impedance matching transformer, which makes it possible to connect a larger antenna to the non-extended whip antenna of every portable. The AA - 1 makes it possible to adjust the antenna signals to the receiver in such a way, that reception is highly improved without overloading- or intermodulation effects. Thanks to the Magnetic Transfer technology of RF Systems, there is no conducting connection between the antenna and the receiver. This protects the receiver from static charges and reduces noise. An external antenna (such as a longwire with MLB) with an AA - 1 adapter connected to the non-extended whip antenna gives often better reception than connecting the external antenna to the external antenna input of the radio (if present).
Improving long- and mediumwave reception.
Portables use a ferrite-bar antenna for the reception of long- and mediumwave signals. The whip antenna or the external antenna input of the portable is not used on these bands, so a large antenna cannot give better reception on these frequencies. The AA - 2 Magnetic Field antenna coupler solves this problem. The AA - 2 coupler transfers the signals of an external antenna to the internal ferrite-bar antenna of the portable by means of a very strong magnetic field, which overrules the noise and interference picked-up by the internal antenna of the radio. With a good outdoor antenna, this gives an exceptional improvement of long- and mediumwave reception.
Small in- and outdoor antennas
Not everybody is able to hang a large outdoor antenna. RF Systems produces a number of small, low-cost wire antennas which are not only ideal for portables, but also for tabletop receivers. They can be used indoors as well as outdoors, hanged out of the window of a hotel room or spanned to a tree during holidays.
* AA - 1 Antenna adapter
Makes it possible to connect a large outdoor antenna to every portable. Continuously variable output level prevents the radio from overload and intermodulation.
* AA - 2 Magnetic Field antenna coupler
Improves long- and mediumwave reception of portables, by transferring the signals of an external antenna to the ferrite-bar antenna of the radio.
* EMF Antenna
A high quality wire antenna with built-in matching transformer and long- and mediumwave pick-up coil. Antenna length only 5 mtrs. In- and outdoor use, with 5 mtrs coaxial lead-in cable. Completely assembled, 50 ohms impedance, frequency range 100 kHz - 30 MHz.
* Mini - Windom Antenna
A very small wire antenna with built-in matching transformer, ideally suited for indoor- and balcony mounting or the use on holydays. Length just 4 mtrs, with 4 mtrs coaxial lead-in cable. 50 ohms impedance, low noise, frequency range 500 kHz - 30 MHz.
* PA 30 wire antenna
A low cost wire antenna with built-in impedance matching transformer. Just 4 mtrs long, suited for indoor- as well as outdoor use, 500 kHz - 30 MHz
Many shortwave listeners use portable receivers. Most portables are designed to work with the built-in telescopic whip antenna. That's fine for the reception of strong stations, but not suited for serious shortwave listening. A larger antenna can give better reception, but connecting such an antenna to the external antenna input of the portable results often in strong noises, whistles and "ghost signals". Reason is overload. Portables are made very sensitive, because the efficiency of the whip antenna is very poor thanks to the lack of a counterpoise. Thanks to this high sensitivity the receiver cannot handle the much stronger signals of the larger antenna, resulting in mostly an even worse reception than with the whip antenna.
A large antenna on every portable
To solve this problem, RF Systems has developed the AA - 1 antenna adapter. This is a special impedance matching transformer, which makes it possible to connect a larger antenna to the non-extended whip antenna of every portable. The AA - 1 makes it possible to adjust the antenna signals to the receiver in such a way, that reception is highly improved without overloading- or intermodulation effects. Thanks to the Magnetic Transfer technology of RF Systems, there is no conducting connection between the antenna and the receiver. This protects the receiver from static charges and reduces noise. An external antenna (such as a longwire with MLB) with an AA - 1 adapter connected to the non-extended whip antenna gives often better reception than connecting the external antenna to the external antenna input of the radio (if present).
Improving long- and mediumwave reception.
Portables use a ferrite-bar antenna for the reception of long- and mediumwave signals. The whip antenna or the external antenna input of the portable is not used on these bands, so a large antenna cannot give better reception on these frequencies. The AA - 2 Magnetic Field antenna coupler solves this problem. The AA - 2 coupler transfers the signals of an external antenna to the internal ferrite-bar antenna of the portable by means of a very strong magnetic field, which overrules the noise and interference picked-up by the internal antenna of the radio. With a good outdoor antenna, this gives an exceptional improvement of long- and mediumwave reception.
Small in- and outdoor antennas
Not everybody is able to hang a large outdoor antenna. RF Systems produces a number of small, low-cost wire antennas which are not only ideal for portables, but also for tabletop receivers. They can be used indoors as well as outdoors, hanged out of the window of a hotel room or spanned to a tree during holidays.
* AA - 1 Antenna adapter
Makes it possible to connect a large outdoor antenna to every portable. Continuously variable output level prevents the radio from overload and intermodulation.
* AA - 2 Magnetic Field antenna coupler
Improves long- and mediumwave reception of portables, by transferring the signals of an external antenna to the ferrite-bar antenna of the radio.
* EMF Antenna
A high quality wire antenna with built-in matching transformer and long- and mediumwave pick-up coil. Antenna length only 5 mtrs. In- and outdoor use, with 5 mtrs coaxial lead-in cable. Completely assembled, 50 ohms impedance, frequency range 100 kHz - 30 MHz.
* Mini - Windom Antenna
A very small wire antenna with built-in matching transformer, ideally suited for indoor- and balcony mounting or the use on holydays. Length just 4 mtrs, with 4 mtrs coaxial lead-in cable. 50 ohms impedance, low noise, frequency range 500 kHz - 30 MHz.
* PA 30 wire antenna
A low cost wire antenna with built-in impedance matching transformer. Just 4 mtrs long, suited for indoor- as well as outdoor use, 500 kHz - 30 MHz
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