COURTENAY 27N 'GRENVILLE' (1952)

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

5-valve dual-wave set using miniature valves. Updated version of the original model 27 from 1949 which used octal valves.

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.

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.

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).

All documented models using this chassis (2 in total)

YEARMODEL NAME
1952Courtenay 27N - this set
1952Courtenay 27M