Cushman ce-31a fm radio test set
These generators are fitted with a variable attenuator (the better instruments have a step attenuator, a fine level control and a level meter). Frequency repeatability is limited by the fact that theoscillator tank circuit is bandswitched. Frequency stability andaccuracy are acceptable on the lower HF ranges, but may be problematicalabove 20 MHz. Asit is a simple free-running oscillator, its spectral purity is excellent,often with close-in phase noise < -140 dBc/Hz. Typically, this type of instrument consists of aColpitts or Hartley oscillator with a high-Q bandswitched tank circuit. The least expensive choice in the military surplus or second-hand market isa tube-type generator. Spare parts availability (especially replacement tubes and custom semiconductors, if applicable) Modulation capability (internal and external)
#Cushman ce 31a fm radio test set generator
The most important criteria to look for in choosing a signal generator are:įrequency accuracy and repeatability (accuracy of dial or readout calibration, and the ability to return to exactly the same frequency) A signalgenerator with a high RF output (0 dBm or more) can also be used as a testsignal source for transmitter alignment, and as a local oscillator forevaluating mixer designs. It is indispensable for receiveralignment, and for the measurement of receiver performance criteria such assensitivity, dynamic range, reciprocal mixing noise and so forth.
Choosing an RF Signal Generator by Adam Farson VA7OJ/AB4OJ Introduction:Īn RF signal generator is without doubt one of the most useful instrumentsone can have in one's shack or home RF lab.