The Columbus model 14 was manufactured for Columbus Radio Centre Ltd by Radio Corporation of New Zealand Ltd in 1945, it was in production for about 4 years.

Known as the Columbus 'Miniatures' (This range also included the model 6 at this time).  There were two model 14 designs using the same 5-valve broadcast band chassis, the Gainsborough (this model is often referred to as the tramcar due to its unusual shape), and the Raeburn.

Columbus model 14 'Gainsborough'

Columbus model 14 'Gainsborough'


Columbus model 14 'Raeburn'

Columbus model 14 'Raeburn'

Bill Heinz noted in his reflections of working at Radio Corp that the model 14 had a special 'holiday time' assembly line of schoolboys - and this led to a lot of dry joints and other issues in the sets.  Those same schoolboys also had training in-house to learn about radio by studying the Hikers One.  What an opportunity that would have been.

Technical Information

Valves (5): 6K8GT, 6K7GT, 6B8GT, 6K6GT, 6X5GT

Intermediate Frequency: 455kc/s

Frequency Bands: 1

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

Released over several years, there was a model 14 chassis, a 14A and a 14R.  Differences are not clear, but from examination the GT valves with metal shields from the 14A appear to be changed to metal valves in the 14R - this could have been done by owners over the years though. 14A models appear in 1945-46 and the 14R appears to be 1946-48.

Servicemens notes on schematics show that models with dial scale part# OE22 use a 3-gang Plessey tuner with one gang unused.

Early models have an upright tuning condeser.  Later models (R-variants) have it mounted more traditionally flat-mounted.

1945 Columbus model 14

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.

Model codes beginning with a 0, for example the model 051, are Osram valve versions of the model without the leading 0. Technically the 0 should be an O (for Osram), however the digit 0 was used throughout the site before this fact was discovered.

The E suffix indicates a magic eye option is fitted (in models which were available with or without, such as the model 25).

A and B suffixes appear to be simply updates to the current model, R also appears to be simply an updated model ('R'edesign, perhaps?)

P indicates either a permanent magnet speaker version of a model which also came with an electromagnet speaker (the model 26 for example), or a portable model (like the model 694P).

N and M indicated miniature valve versions of a model which started with all (or a mix, ie: model 5) of larger valves. One of these two codes may indicate a transitional mixture of octal and miniature - clarification is required.

S often indicates a stereo model.  It can also indicate 'self-biased' in the transition period between back-biased and self biased sets where there were models with both methods employed (53S for example)

Finally, other suffixes and prefixes make occasional appearances in the RCNZ lineup - like the 66W (a variant of the long-running model 66) and the 75XA (a 10-valve version of the model 75 with a separate amplifier chassis).