From a qsl.net post:
The Harvey-Wells Company was formed through a partnership between Clifford Harvey~W1RF, and John Wells~W1ZD in 1939.
Cliff Harvey had earlier founded Harvey Radio Labs in 1933, and prior to that, he was associated with the Hendricks and Harvey Company, another partnership. Producing police radios, transceivers, transmitters, and crystals. Their most popular product was the TBS-50 transmitter introduced in 1947, covering the 80 through 2 meter bands. In 1948, a three tube audio preamp was included, carrying the TBS-50 A model number. The last model produced was the Bandmaster T-90 ceasing in 1960.
Single side band emission became the emerging mode of choice. Harvey-Wells had no design for this type of modulation, and with nothing to offer the market place, faded into history.
Country: United States of America (USA)
Manufacturer / Brand: Harvey - Wells, Southbridge MA
Year: 1949 Category: Transmitter (TX not Transceiver)
Valves / Tubes 8: 6AQ5 6AQ5 807 6L6G 6L6G 6AU6 6AU6 12AU7
Wave bands Short Wave (SW only)
Power type and voltage Powered by external power supply or a main unit.
from Radiomuseum.org Model: Bandmaster Deluxe TBS-50D - Harvey - Wells, Southbridge MA
Material Metal case
Shape Tablemodel, high profile (upright - NOT Cathedral nor decorative).
Dimensions (WHD) 9 x 13 x 8 inch / 229 x 330 x 203 mm
Notes Transmitter, AM / CW, covers 80 - 2 m ham bands.
Optional APS-50 mains power supply, DPS-50 dynamotor or VPS-50 vibrator pack supply, optional external VFO. 3 tubes microphone preamplifier for use with crystal microphone already installed.
Improved version of TBS-50 with crystal control / external VFO-connectors.
Price in first year of sale 138.00 $
Source of data -- Original prospect or advert
Literature/Schematics (1) 1951 Newark catalog Nº 51