The Columbus model 27 was manufactured for Columbus Radio Centre Ltd by Radio Corporation of New Zealand Ltd in 1948, production ran for 3 years.
This model is part of the Columbus Exeter series of radios.

5-valve dual-wave set.  Superseded by the model 27N which used miniature valves.

1948 Columbus model 27

The Columbus model 27 is part of the Columbus Exeter series of radios.

The models 27 and 32 were the broadcast band and dual wave (respectively) table models from Columbus in 1948.  The cabinet style was pretty standard for sets from Columbus around this era.

The radios in this series are:
1947 Columbus model 32 Exeter
1948 Columbus model 27

Valves (5): 6K8, 6K7, 6Q7, 6V6, 6X5GT

Intermediate Frequency: 455kc/s

Frequency Bands: 2

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

Original lab drawing for the model 27, 6 November 1947.  These lab schematics were distributed as photographs, presumably the quickest way at the time for them to mass copy information to allow Columbus Radio Centres and Turnbull & Jones service agents access to service info before the official documentation had been prepared and printed.

1949 Columbus model 27 lab schematic

Official schematic, 2 September 1948 - almost one year later.

RCNZ Model 27 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)

1948Columbus model 27 - this set
1948Courtenay model 27