The Columbus model 515 was manufactured for Columbus Radio Centre Ltd by Radio Corporation of New Zealand Ltd in 1957.

5-valve broadcast mantle radio, available in 5 colours. Sighted ivory, grey, blue and burgundy. Fifth colour is?  Brown?

Two different dial glasses - both with red wire soldered to the drum as a pointer. 

Note: blue set photographed has been resto-mod'd and pointer is now yellow while cabinet is painted to deal with cracks - the chassis is restored to factory.

This set is similar to the Astor / Columbus 525 and the Astor FEU

Valves (5): 6BE6, 6BA6, 6AV6, 6AQ5, 6X4

Intermediate Frequency: 455kc/s

Frequency Bands: 1

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

NB: Some sets are IF-peaked at 465kc/s as per note below

1957 Columbus model 515 IF Peak Notes

1957 Columbus model 515 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.