Here is a video I made of a 12" 5-tube Zenith hybrid showing the chassis and tubes. I still need to hook it up to a good signal source and check tuner performance...wasn't able to get very good reception on rabbit ears. I said on the video I thought it was made in Korea but actually it's Taiwan.
http://www.youtube.com/watch?v=E_rIG19SUa0
The set uses completely point-to-point wiring on terminal strips except for the solid state modules. It doesn't use the solder cone terminals like the American Zenith sets.
A few tube radios did have the instant on feature, using the diode like in the TVs...I have a Westinghouse FM-only set from the 60's which does.