Hi Donald
“Driving you to distraction” doesn’t sound good…
Is it all those suppressed memories of bygone days?
So I also did my homework, and the valve in question is an EK32 ‘octode’, rather then the ‘heptode’ I’d thought it was.
This has six grids in three columns, and some of those are used as plates (I’m told).
This valve was used in the rf front-end of the radio, acting as both an amplifier, a the local oscillator and the down-mixer for the following if stage.
So the lesson here is that the quality of thinking and the novel ideas of good engineering don’t change with time; just the technology that we have to work with is different.
Interestingly, vacuum tube technology lives on in the travelling-wave guides used in satellites and in the development of vacuum channel transistors for use in terahertz equipment for directional high-speed communications and hazardous-materials sensing.
Finally, you’re right about the high operating voltages inside the old Tektronix valve scopes, but those are beautifully-crafted pieces of engineering, well-documented and easy to move around in safely. And even back then – in the 1960’s – they understood that the electron beam in a vacuum had a finite speed, and so developed distributed electrode methods for high-speed analogue CRTs (cathode ray tubes).
Knowing your electronics history can help with modern design work.

Thanks chaps
Ron – I’m sure that the cadetships would have been invaluable to those young graduate engineers in giving them some confidence and usefulness from their first day in a real job.
The difficulty I have is the high cost to a small company of funding the cadetship, even at a half-time salary. Yes, the cash is hard to come by, but the teaching time needed is the biggest drain.
It’s still worth doing though.
One of the greatest moments during an internship comes when you realize that the intern has just told you something, or done something, that you yourself hadn’t thought of, didn’t know or could not have found time to do. That ‘tipping point’ may be reached after as little as one month with a very bright student. After that they are worth having around, and are a positive influence for all.
Don – I haven’t many clues about accounting so have never interned anyone from that field. I wonder whether – dealing as they do with figures and computing systems – they are more ‘job ready’ than engineers?
Maybe you have also touched on the real problem here with graduate engineers. Their lack of vocational skills – the sort of nouse that you would expect of a technician from the TAFE – is something that engineering graduates simply have had too little time to develop? I think of this as ‘bench skills’. One Masters Student (Chinese) didn’t know what an oscilloscope was.
As the great Jim Williams (Linear Technology’s electronics guru) said: “Always solder and debug your own circuits – don’t just flick them over to some hapless technician to sort out after you designed it” (paraphrased with a wide license)