Utilization of the Hall effect in the frequency conversion of microwaves with gain was investigated. A conversion gain which seemed to be feasible was found to be dependent on the control sensitivity of the conversion system. A high control sensitivity can be achieved through use of a high‐mobility Hall sample, like InSb, an efficient coupling of a modulating field to the sample, and a suitable high‐energy pump source.The high‐power test was performed by using a pulsed microwave pump. Conversion gains were measured as a function of the pumping power and showed some ``saturation'' effects. These effects were explored and explained, based on the behavior of carriers in the sample under high‐power microwave fields. In particular, a breakdown field beyond which the saturation seemed to disappear was found.The presentSband experimental model still suffered a conversion loss of 25 to 30 dB. Results have, however, revealed the possibility of a practical microwave Hall converter with gain.