12-07-2017, 09:06 PM
(11-07-2017, 08:24 PM)ed731pdh Wrote: It's the mentality I suppose. Why should I design something from the ground up when I can order a module that does what I want from a far east sweatshop for a minimal cost. The only ball breaker being the time to get the part over and through customs.
If we are not training up electronics designers now, things are not looking too good for the UK.
I think that this is the op's real point, if the foundation of any discipline is not taught, then how can the student see how this modular approach actually works, and if they don't understand then they are poorly equipped to make any independent advance. Yes, the basics are taught, but they are very much glossed over in comparison with how things were forty years ago.
I know that "digital" is the glamorous side of electronics, but designers are so wrapped up in finding the digital solutions, that often an analogue one is more easily realised. A company I work for has recently sent me on a "jolly" to see a new process control system in action at another companies factory.
Their process is similar, and I took particular interest in the motor load control that they use on the hammer mills that they have, it involves:
1. A hall effect current transformer that feeds into an analogue signal conditioning circuit
2. A V to F ADC.
3. A bespoke com's i/o board.
4. A dedicated PC.
5. A DAC that outputs a 4-20mA signal,
6. A 4-20mA to 10V current to voltage convertor
7. A phase angle pulse generator phase locked to the same supply as the machine vibratory feeders
8. A power thyristor module
The system pid settings are unavailable to the user, and any menu selected settings are only available to the suppliers technicians to alter via a password system, at £45 per hour + 50pence/mile and £35 per hour travel, no online support is offered on grounds of, guess what, yup, health and safety!
The system installed "back home" circumvents items 2 through 7 with a purely analogue realisation using one LM 324, two CA3080E's a couple of voltage reg's, five transistors and a few other bits of little cost, it works well and has done since installed in 1993.
Digital progress?
Its progress where it allows us to do things that we couldn't before, or better than before, or more economically than before.
Its not progress when a digital solution is the only thing that the designer understands, or its used in the financial taking down of the consumers trousers.
A quote that sticks in my mind is from Roland Moreno, inventor of the smart card, in an interview with Electronic Times. "Digital is easy. Analog ........ that's professional.
Cheers,
Andy.
