EICO 460 simulation

examination

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It's a truly, truly brave man who will attempt that level of simulation from scratch :-). The answer is that Yes! it is feasible, (but not in it's entirety). The circuitry you would finally get on screen could not include the very important scope' tube. nor would any of the numerous switches and pots be directly useable. Items such as the HT transformer would have to be modelled specifically, even though that extreme level of detail will not be in the documentation. Even with the best will in the world, the end result would only be a simplified, rough approximation of the actual 'scope circuitry. Simulation time would also be horrendously slow with numerous convergence failures. OTOH ... A complete functional block, something like that 'orribly complicated looking 'Y' amplifier, or the 'X' timebase driver, would simulate nicely and a lot could be learned. Best of luck! regards john

I'm sure a very ignorant optimist will suffice. :)

It did seem like a lot to ask. On the other hand, I recall reading, maybe

10 years ago or more, that the advent of supercomputers offered the possibility of simulating an entire airplane, instead of just parts of it which then had to be assembled and tested to evaluate the ensemble. This was hailed as a way of designing passenger planes that would fly near the top of the atmosphere would get you from New York to Tokyo in half an hour. So, I just figured that if they could contemplate that, why not my dinky little EICO 460?

I don't know what it means to simulate the oscilloscope tube in this context. Does it mean to simulate it as a circuit element or does it mean to worry about the electrons and fields and heat? I guess it means both, since ultimately I'd want to know what is going to appear on the oscilloscope screen.

I did a search of

for math papers whose reviews contain the words "cathode ray tube" and found a few that try to model it directly and several which try to use the tube to present graphs of solutions to differential equations and other problems. I can't say without looking at the papers, but that does sound as though they must have considered some aspect of the simulation problem for the crt in order to do that.

Regarding the switches and pots, they describe the state of the scope. Part of the simulation can be to let the user specify some functions that will govern the state of the pots and switches at each moment of time. Likewise, the device one is hoping to connect to the oscilloscope can be simulated either by a function describing the input signal (treating the device as a signal generator) or by writing the circuit for the device and grafting it onto the circuit for the oscilloscope.

When I use words like "can" here, I don't necessarily mean possible, merely conceivable at my low level of understanding.

When you talk about modeling the HT (what is HT?) transformer specifically, I gather that means you have to worry about details of its construction, geometry and winding that you might only know from taking it apart. If you did know all that, what kind of software would model it?

Alternatively, maybe one could remove the transformer and use a computer controlled device to test it and store a lookup table of its behavior under various conditions.

Since my scopes are in storage, it will be faster than actually trying to use them. :)

I'll take a look at the schematics. Thanks for the suggestion.

Ignorantly, Allan Adler snipped-for-privacy@zurich.ai.mit.edu

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