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The Vector-Finder Types VF-121 and VF 121A are unique in the Vector-finder series of direction finding antennas. They incorporate a proven design, electro statically shielded loop sensing element with modern solid state low noise analog and digital technology to allow detection and location of aircraft band signals. Both the VF-121 and the VF 121A incorporate a unique digital modulator which allows the user to more easily home-in on unmodulated carriers. Such cases occur at airports when transmitter may be accidentally keyed on during aircraft overnight layovers. The VF-121 is specifically designed to be used on airport premises where signal strengths are high. To compensate for very strong signals, an integral attenuator is also incorporated to allow the user to operate the unit close-in to aircraft. The VF-121A differs in that a high gain, low-noise preamplifier is utilized with the sensing element in order to hunt signals that may be weak or at a distance. The unit is ideally suited for the location of ELT transmitters in the field. Both units are tunable over the 118 MHz to 130 MHz aircraft frequencies and interface directly to the user’s aircraft band receiver or transceiver via the antenna jack. With the antenna system connected to the receiver, the user will hear the desired signal. If the signal is unmodulated, the digital modulator will generate a tone on the carrier. When the handheld unit is rotated about, an audible null on the received signal or the generated tone will be heard. This null aligns with the axis of the equipment case and represents the direction of the received signal. This direction may be read from the black dial compass mounted on the top of the enclosure. As the response is bi-directional, triangulation may be used to determine the true bearing when the true direction is not known.


VF-121 Frequency Range: 118-130 MHz, front panel tunable

VF-121A Sensitivity: VF-121, Approx. –10 dB

VF-121A, Approx. +10 dB

Attenuation: Fixed –40 dB step, front panel switched

 Power Requirement: Single 9 volt battery, rear panel mount

Size: Compass Top to Handle Bottom: 11 ¾ in.

Front to Back depth: 7 ½

Width: 3 ½

Interface: Standard BNC Male connector, will interface with any 50-75 ohm impedance receiver, 2 ½ feet feedline, customer specified connectors at additional cost.

Price: VF-121 $249.95

VF-121A $329.95

Shipping, UPS Ground, $6.50

California sales tax when applicable


Note: The customer is responsible for providing the necessary radio receiver to interface with this hardware.

Overseas Customers: Please note that an additional overseas shipping charge will be applied to your order. National RF will notify you of the exact amount of shipping to your country via e-mail, after your e-order is placed. The customer is responsible for all and any customs or tarrif charges applied to your order.


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