Search results
Results from the WOW.Com Content Network
The AN/URM-25 was part of a series of vacuum tube-based signal generators built for the U.S. military in the early Cold War-era.. Today they are collected and used by vintage amateur radio and antique radio enthusiasts who say they provide reasonably high accuracy and stability for a low cost, with build quality reflecting tough military construction requirements and standards.
The power may be either in linear units, or logarithmic units (dBm). Usually the logarithmic display is more useful, because it presents a larger dynamic range with better detail at each value. An RF sweep relates to a receiver which changes its frequency of operation continuously from a minimum frequency to a maximum (or from maximum to minimum).
An RF switch or microwave switch is a device to route high frequency signals through transmission paths. RF (radio frequency) and microwave switches are used extensively in microwave test systems for signal routing between instruments and devices under test (DUT). Incorporating a switch into a switch matrix system enables you to route signals ...
Several countries in ITU Region 1 have access to frequencies in the 70 MHz region, called the 4-meter band. The band shares many propagation characteristics with 6 meters. The preferred location for beacons is 70.000–70.090 MHz; [5] however, in countries where this segment is not allocated to Amateur Radio, beacons may operate elsewhere in ...
The S stands for "Strength". Strength is an assessment of how powerful the received signal is at the receiving location. Although an accurate signal strength meter can determine a quantitative value for signal strength, in practice this portion of the RST code is a qualitative assessment, often made based on the S meter of the radio receiver at the location of signal reception.
Cable length limits the controller-device distance to two meters per device or 20 meters total, whichever is less. This imposes transmission problems on systems spread out in a room or on systems that require remote measurements. Primary addresses limit the system to 30 devices with primary addresses. Modern instruments rarely use secondary ...
The RF signal is detected and fed to a microammeter, which is scaled in dBμ. The frequency range of the tuner is usually within the terrestrial broadcasting bands. Some FS meters can also receive satellite (TVRO and RRO) frequencies. Most modern FS meters have AF and VF circuits and can be used as standard receivers. Some FS meters are also ...
A signal sent by an ideal transmitter or received by a receiver would have all constellation points precisely at the ideal locations, however various imperfections in the implementation (such as carrier leakage, low image rejection ratio, phase noise etc.) cause the actual constellation points to deviate from the ideal locations. Informally ...