The Philips 666D was manufactured by Philips Electrical Industries of N.Z. Ltd in 1936.
6-valve dual-wave radio, Made by Radio Corp. NZ
This is the MKII version of the model 666A
Changes included a newer valve lineup, the tone control moved to the front and circuit improvements including an Intermediate Frequency modification to solve issues with the earlier model not operating well in Christchurch or Dunedin (see the service information of the 666A for more details).
Valves (6): E447 or AF2, AK1 or AK2, E447 or AF2, E444, E463 (All US 6- or 7-pin base versions)
Intermediate Frequency: 456kc/s
Frequency Bands: 2
General Construction Notes for Philips Electrical Industries of N.Z. Ltd:
Model codes are explained on the Philips brand page. Philips early-mid century were probably the Google of their time - they had branches in many countries and a global brand that everyone knew - and were apparently happy to let engineers come up with new ideas and implement them. Construction is often overly complex but very well engineered - although repairs can also take a complex path. They used time-in-motion studies to find the most cost effective way to asemble sets and sometimes this means repairs can be nightmarish (if you've ever worked on a V7A Theaterette this will be all too aparent). U suffix model numbers are transformerless (hot chassis) sets and great care should be taken, or the sets avoided altogether.