The Courtenay 27M was manufactured for Turnbull & Jones Ltd by Radio Corporation of New Zealand Ltd in 1952.

5-valve dual-wave set using miniature valves. Final version of the model 27 series of radios (27, 27N and 27M) - seems to just be minor updates from the 27N.

Valves (5): 6BE6, 6BA6, 6AV6, 6AQ5, 6X4

Intermediate Frequency: 455kc/s

Frequency Bands: 2

Chassis Notes(most schematics can be clicked to download a full size version)

N & M variants are very similar - a note on the schematic from a previous radio serviceman suggests some N variants may have a 6V6 instead of the 6AQ5, possibly indicating the 27N was a transitional model between the 27 (octal) and 27M (miniature) - this could be due to stocks of the 6V6 that Radio Corp NZ was trying to use up before moving on to miniatures, or possibly even supply issues with the new miniatures.  Also note the different tuning gang with round plates rather than the shaped plates of the 27N.


RCNZ model 27N and 27M Schematic


General Construction Notes for Radio Corporation of New Zealand Ltd: The first digit of the serial number typically indicates the year of manufacture of RCNZ chassis' (although not the decade - that requires a little knowledge of the valves, construction, etc). Sets from around 1934 onwards were often (but not always) constructed in a distinctive pressed 'baking pan' style chassis, seemingly unique to RCNZ.

All documented models using this chassis (2 in total)

1952Courtenay 27N
1952Courtenay 27M - this set