The Music Master STD 5B was manufactured by Melhuish Radio Co. in about 1955.

4- or 5-valve broadcast mantle set (4 + diode perhaps?).  Appears to be similar in style to the sets of the post-war decade but the year is a guess based on the serial number of the ARTS&P label and certainly not in line with its appearance.  As seen for sale, no further details.

Valves (4 or 5?): 6AQ5 output?

Frequency Bands: 1

Chassis Notes(most schematics can be clicked to download a full size version) This was probably quite a late 4 or 5 (or 4 with solid state rectifier?) model in the valve era.  Serial number suggests 1963 which seems a little late.