COLUMBUS MODEL 402 'PORTABLE' (1947)

The Columbus model 402 was manufactured for Columbus Radio Centre Ltd by Radio Corporation of New Zealand Ltd in 1947, production ran for about 4 years.
This model is part of the Columbus Portables series of radios.

6-valve broadcast band dual-power portable radio.  Mains or battery, internal loop aerial.

1948 Columbus model 402

The Columbus model 402 is part of the Columbus Portables series of radios.

This series contains all the known Columbus portable radios - including a few transistor portables from the final few years of the brand.

The radios in this series are:
1941 Columbus model 201 Portable
1947 Columbus model 301 Portable
1947 Columbus model 402 Portable
circa 1948 Columbus 402Z Portable
circa 1948 Columbus 402X
1952 Columbus model 502 Portable
1955 Columbus model 653 Portable
1959 Columbus PZ117 Transistor Seven
1959 Columbus 694P Transistor 6

Valves (6 (or 5)):
1N5, 1A7, 1N5, 1H5, 1A5, 1A5
1N5, 1A7, 1N5, 1H5, 3Q5 (s/n 84401 onwards)
1T4, 1R5, 1T4, 1S5, 3S4 (model 402A)
1T4, 1R5, 1T4, 1S5, 3V4 (model 402Z)

Intermediate Frequency: 455kc/s

Frequency Bands: 1

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

At least three variations on the base schematic - from serial number 84401 the original twin-parallel 1A5's are replaced with a 3Q5.  And the 402Z appears to be an almost complete redesign around miniature valves.

 

1948 Columbus model 402 Schematic

1947 Columbus model 402A Schematic

1948 Columbus model 402Z Schematic

1947 Columbus model 402A

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 (3 in total)

YEARMODEL NAME
1947Columbus model 402 - this set
1948Columbus 402Z
1948Columbus 402X