There are very stable synthesised signal generators from a few kHz to 2.6GHz. A number of spectrum analyser tracking generators (very useful) and general purpose signal and pulse generators also principally used in equipment development. A typical system connection diagram for 1420MHz using the 3m Dish and circular waveguide feed is shown below.
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One of the most difficult aspects of operating a very sensitive system of cascaded high gain amplifiers is that of temperature stability. The 40dB gain in the antenna head amplifiers and the 18dB gain in the RF line driver amplifier are out of doors and are sometimes subject to temperature variations in excess of 300C over the 24 hour period of some observations. Active temperature control of these critical gain stages is essential and is achieved using a closed loop temperature sensor I.C. and Peltier Cooler/Heater mounted on a heat conduction plate on to which the amplifiers are fixed.
See construction of 408MHz Head Amplifier
See construction of 1420MHz Head Ampifier
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