The active monopole antenna VAMP 9243 consists of a vertical rod and an impedance matching amplifier. The rod has a standard length of 1m (other rod lengths on request) and can be considered as short compared to the wavelength in the frequency range 9 kHz-30 MHz. The conversion factor is independent of the frequency because of the extremely high impedance of the matching amplifier. The circuit gives the best results of noise and intermodulation for a conversion factor (antenna factor) of +10 dB and sensitive measuring receivers are able to use the whole dynamic range of the antenna.

For very high field strength, an optional plug-in attenuator reduces the amplification by 20 dB. In order to avoid absolutely any influence by the mains, power supply, voltage regulator a. o., the VAMP 9243 has built-in NiMH rechargeable batteries. The typical operation time is at least 50 hours. Charging time is 2-4 hours using the quick charger. The Rod antenna and amplifier cabinet are made of aluminum. The top plate can be fixed to the metal ground plane (Counterpoise) with 4 screws.

The connectors and controls are situated below the top plate. The rod length begins exactly at the top plate.

VAMP 924

    Options

Opt. GP: Aluminium-Groundplane, 0.6 x 0.6 m

Opt. ACS 410: Charger ACS 410

Opt. VT: 20 dB plug in divider to measure high field strength
[Picture]

Opt. CA 9243: Calibration Adapter for VAMP 9243

Opt. MIL461F bonding kit:

Bonding kit for VAMP 9243 acc. MIL-STD-461F consisting of a BNC

cable double shielded ca. 70 cm, with braid

current blocking ferrite in the center, elbow aluminium angle

with BNC bulkhead adapter.

    Low Noise Active Verticle Monopole Antenna 

 1. Overview VAMP 9243

The active monopole antenna VAMP 9243 consists of a vertical rod and an impedance matching amplifier. The rod has a standard length of 1m (other rod length on request) and can be considered as short compared to the wave length in the frequency range 9 kHz-30 MHz. The conversion factor is independent of the frequency because of the extremely high impedance of the matching amplifier. The circuit gives best results of noise and intermodulation for a conversion factor (antenna factor) of +10 dB and sensitive measuring receivers are able to use the whole dynamic range of the antenna.

For very high fieldstrength, an optional plug-in attenuator reduces the amplification by 20 db. In order to avoid absolutely any influence by the mains, power supply, voltage regulator a. o., the VAMP 9243 has built-in NiMH rechargeable batteries. The typical operation time is at least 50 hours. Charging time is 2-4 hours using the quick charger. Rod antenna and amplifier cabinet are made of aluminium. The top plate can be fixed to the metal ground plane (Counterpoise) with 4 screws. The connectors and controls are situated below the top plate. The rod length begins exactly at the top plate.

2. Technical Data 2.1 Frequency range: 9 kHz - 30 MHz 2.2 Conversion factor ("Antenna factor") +10 dB/m+-1.5 dB 2.3 Upper limit of field strength measurement: 1 V/m (F=1 MHz, 1 dB compression) Input attenuator for higher field strength optional 2.4 Lower limit of field strength measurement: Limitation by internal noise. Typ. - 3 dBµV/m / 10 MHz CISPR-Quasipeak 9 kHz bandwidth Typ. -8 dBµV/m / 10 MHz Average detector 9 kHz bandwidth More information is given in the diagrams further down this manual. 2.5 Output of the monopole amplifier: BNC-connector, fem., 50 ? nom. 2.6 Power supply: 9,6 V /1100 mAh NiMH 2.7 Dimensions and weight: Monopole (Rod): Length including thread connection 1m Weight approx. 0,2 kg Amplifier: 180x80x40 mm (WxHxD) without BNC-connector (female) and controls. Top plate 220x120 mm Weight approx. 0,7 kg 2.8 Construction of the monopole (Rod): Aluminium rod 16 mm diameter with thread-hole M8 2.9 Construction of the amplifier: Cabinet made of aluminium profiles. Top plate 3 mm aluminium material. 2.10 Threads for tripods: 1/4", 3/8" ABSOLUTE EMC Llc. Covering sales in North America United States, Mexico, & Canada ab Put ON/OFF switch into ON-position. The green LED has to be on. Combinations of green and red LED: Green: Battery OK Green + red: Battery reserve Red: Low battery The antenna will operate even with low battery, but with restricted performance.

2. Application

 Basically the active monopole antenna is an electric field strength adapter. In combination with our magnetic field probes, for example FMZB 1537, electric and magnetic field strength can be measured separately with high sensitivity in the frequency range from 9 kHz - 30 MHz. Standards, especially in the automotive field, give very precise specification for the measuring site. Usually the monopole antenna is mounted on a metal (electric) counterpoise. Measurement is made in a shielding room.