By use of two mixers and a common variable local oscillator, a super‐heterodyne receiver, such as General Radio Wave Analyzer No. 736‐A, can be converted to serve simultaneously as generator and detector. Such an arrangement provides: (1) single dial tuning, (2) absolute freedom from relative frequency drift, (3) the possibility of very narrow band tuning and, thus, improved signal‐to‐noise ratio. Circuits to accomplish this are described for the range 0–16 kc which occupy no more space than a conventional oscillator, which they replace. Extension of the frequency range to 0–600 kc is possible by simple changes and the use of an RAK‐7 commercial receiver, although in this case single dial tuning is not possible. These circuits are particularly useful for automatic balancing dielectric bridges, but should also be very useful in work with vibration and sound, and for filter and amplifier frequency response.