The transceivers described here include, in the order they were produced, the TS-520, TS-520SE, TS-820, 820S, TS-530S, TS-530SE, TS-530SP, and TS-830S.  They were developed and manufactured in the 1970s and 1980s by the Japanese company Kenwood (formerly Trio) for amateur radio enthusiasts and are popularly known as the Kenwood 'hybrids."  They are mostly solid state, but at the time they were first produced, high power transistors were not economically viable for amateur products.  So to achieve the desired 100 Watts continuous wave output, Kenwood's engineers turned to vacuum tubes -- a 12BY7 driver and a pair of S2001A (6146B equivalent) final amplifiers.  This hybrid combination of solid state technology (reliable, low power consumption) and vacuum tube technology (high efficiency, linearity) proved to be extremely successful and popular with radio amateurs over almost 25 years of production.  Each new model incorporated additional features and performance improvements while retaining the best of the previous model, and they are still used by serious amateurs around the globe.
Kenwood produced its first all solid state transceivers in the mid 1980s, and among these the most popular is the TS-940S.   It is included here as a representative example of the Kenwood solid state transceivers.
Click the links below for brief descriptions of each model.  These are photographs of actual transceivers repaired, aligned, and/or refurbished by Old Ham Dave.