RF Wattmeter - FIT 70

The FIT Series RF wattmeters are hand-held, low-cost instruments for quick tests of digital (cellular) and analog radio communications systems. They are service-testers and Point-of-Sale testers for mobile phones which allow fast Go / NoGo decisions at the first level of diagnosis before they are returned to the manufacturer's maintenance center. This reduces down times, handling costs and ensures that only defective units will be returned. Of course the FIT Series also improve the image of the retailers at the Point-of-Sale. Operation is so simple that everyone can use the FIT after a few minutes of training.

SCHOMANDL offers different FIT model RF wattmeters depending on the application and required frequency range. The FIT 70 covers from 70 MHz to 1000 MHz. This frequency band can check most of the international analog and cellular mobile networks such as GSM 900, AMPS, D-AMPS, TACS, NMT 450/900. The lower frequency band is used for private mobile radio - PMR, at police and fire departments, taxis, customs, etc.  

 

FIT70 RF Wattmeter

 

Features and Accessories for the Fit 70 RF Wattmeter

The FIT (series) comprise a base unit and remote measuring probe. The separate RF-head is inserted without long interconnection cables between the transmitter output of the mobile radio and the antenna cable, thus avoiding additional measuring errors. Just measure the power output by the transmitter and the power reflected in either Watt or dBm. Instead of reflected power, it is also possible to display the VSWR on the high-contrast LCD. These are useful parameters to determine the quality of the systems components and the workmanship of the installation. The FIT Series identify automatically whether a continuous analog RF signal or bursts from a cellular system are applied. The storage of max. and min. values permits the detection of intermittent problems, for example during the engine start. In case of a short-circuit in the antenna or in the antenna cable, a red LED on the RF-head gives a warning.

RF workshops that support not just mobile telephones but also mobile radios and B.O.S. radios (German emergency services) require the FIT 70, which covers the frequency range from 70 MHz to 1000 MHz.

All FIT models have a built-in, fast converting DC voltmeter with minimum-/maximum- storage and a ohmmeter. There is no need for any extra instrument to locate further malfunctions in the vehicle's electrical system, in car installation kits or AC/DC chargers. The separate basic instrument permits easy use and read-out of test results in numerical or bar graph display.

Useful accessories for the FIT testers are the transportation box (lined with dense foam to provide maximum protection) and the RF-adapter set (connects the FIT to the most common mobile phones).

 

Measuring with the RF Wattmeter

The FIT sets are each supplied with one measuring probe for the related telephone network GSM 1800 or GSM 900 and DCS 1800. The radiation emitted by the mobile phone's transmitter antenna is measured at a defined distance (7 cm). To check this distance, appropriate templates are included in the items supplied. The FIT with the power radiated from the antenna is a valuable aid for checking mobile phones that are installed in vehicles. The power radiated by the antenna can be compared with the power output by the transmitter. In this way, excessively high losses in the pane of glass used for bonded antennas can be demonstrated.

 

Key Features of the FIT 70