The lightweight 3500 Radio Test Set now allows the user to measure VSWR versus frequency and return loss. The return loss of a cable is displayed in graphical form as return loss versus distance, making it easy to determine the exact location and magnitude of a cable fault. The VSWR of an antenna is also displayed graphically as VSWR versus frequency. By using the setup for frequency start, stop and span, the user can select the exact frequencies for sweeping the cable or antenna. Up to six markers can be used in analysing the graphically data that is acquired for SWR (Standing Wave Ratio) or DTF. The markers display precisely the return loss at a given distance for DTF mode or the exact VSWR at a given frequency for SWR mode. A delta function, associated with the markers, is also available to show the difference in VSWR and frequency, or return loss and distance in feet between two of the markers.
A key issue for radio transmission and reception is call quality. With the addition of squelch tones, call quality of the radio’s receiver can be monitored with two internal modulation sources. Two sources, GEN1 and GEN2 now have the requisite 0.1Hz resolution for modulation rate. This allows the 3500 series to generate the necessary squelch tone with one of the generators and a test tone with the other generator. The user can then analyse call quality and make adjustments as required.
In addition, the 3500 Series allows users to define pass/fail parameters. Users can configure the test parameters and then save these files internally for future use. This enables fast testing on radios that require constant testing, for base station verification, and for testing a large numbers of the same type of radio.
Since many radio system faults actually originate in the cabling or antenna rather than in the radio, the Aeroflex 3500 Radio Test Set conveniently allows maintenance technicians and other personnel to measure the VSWR of both the cable and the antenna. A large VSWR can indicate a high return loss caused by a bad cable, connector, or antenna. Isolating the problem in the cable, connector or antenna prevents the user from returning a good radio to the manufacturer or depot for repair, thus avoiding unnecessary extra cost as well as the inconvenience of radio system down time.
The Aeroflex 3500 Radio Test Set weighs just 8.5lbs. (3.86kg.) including the battery and solid aluminium weatherproof case. It has an operating temperature of -20°C to +55°C, and is designed with rugged construction specifications for humidity, altitude, shock and vibration. It has a battery life of five hours and can be fully recharged and ready to operate in only four hours. When not in use, the Aeroflex 3500 Radio Test Set and the optional accessories can be easily stored and transported in a sturdy carrying case.
The Aeroflex 3500 Radio Test Set is designed to enable quick “Drive-By” testing, allowing the user to connect to the supplied antenna, key up the radio and measure the radio parameters over-the-air. A microphone/speaker combination handset is provided to check voice quality of the transmitter and receiver.
Utilising a software-defined radio architecture, the 3500 Radio Test Set is easily upgraded with new features. The software defines almost all of the functionality of the test set from the RF physical layer and above. Users can easily add options or update functional improvements in the field without the need to return the instrument to the factory.