Several miniature tunable short-wave receivers were designed, built, and evaluated, using two types of fabrication techniques. One type used chemically deposited resistors and conductors, with the remainder of the components placed in holes in the glass substrate; the other type used all miniature components mounted on an etched circuit board. Both receiver types have a volume less than 0.5 cu in. Novel features include a newly developed shielded, dual-section, miniature, variable tuning capacitor and miniature pretuned, toroidal, IF transformers. The receiver has a sensitivity of about 1 μv and a power consumption of 12 mw. The tuning range extends from 12 to 18 Mc.
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