RME DB-22A
RME DB-22A
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The RME (Radio Manufacturing Engineers) DB-22A is a preselector with continuous coverage from the broadcast band through 40 MHz. It matches the cosmetics of the RME-84 and 45 but was used with a variety of receivers. The earlier DB-20, the black version of which matches the RME-69, was used extensively as a pre-selector for sea-going vessels during WWII. Part of the motivation was reportedly to alleviate some of the fears of a receiver's local oscillator being detected by enemy direction-finding equipment. The preselector places three tuned circuits including two active stages between the antenna and the receiver therefore further isolating the antenna from the local oscillator.