EXELRAD AIR KING DUAL WAVE (CIRCA 1936)

The Exelrad Air King dual wave was manufactured for Turnbull & Jones Ltd by Radio Corporation of New Zealand Ltd in about 1936.

The cabinet bears a sticker : "Made by Jackson & King, Holland St, Wellington".

The chassis has no identifying information. The circuit and chassis layout are identical with the Exelrad Air King 6-valve dual wave model of 1935, except for the valves which are 6.3V instead of 2.5V types.  Note that the circuit and chassis layout are different from the 1936 Exelrad models 6D and 6DXI.

This set has a silver plaque on the front stating: "Wellington Cricket Association - Presented to P.B Broad for services rendered to Wellington cricket 1921-1936"

Valves (6): 6D6, 6A8, 6D6, 6B8, 42, 80

Intermediate Frequency: 465 Kc/s

Frequency Bands: 2

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

Service information (Exelrad_Air_King_-_6V_DW_AC_-_1935.pdf) here

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).