wiz@xroads.UUCP (Mike Carter) (01/27/89)
After rummaging through stockpiles of books at just about every bookstore here in AZ, I am amazed to find that truly good electronics projects books are a very *RARE* find. Is everyone buttoning up on experimentals and schematics these days, or am I imagining that the same projects from 10 years ago are being regurgitated over and over again in all the electronics magazines? (i.e. BUILD THIS STEREO-T.V. DECODER, PART MMCXLV, or FORREST MIMMS plays with J-K Flip-flops etc etc et al ad nauseam...) I've been collecting project books over the years and find them to be an invaluable source for getting parts of circuits done quickly without too much hair-pulling. Anyone got ideas or sources ? "We have control of the Horizontal, We have control of the Vertical..." -Mike @ XROADS!
wiz@xroads.UUCP (Mike Carter) (01/31/89)
I'm re-posting this article I received as a response. Permission was granted to do so, although I claim no responsibility for its contents. ---------------------------------------------------------------------- Subject: Re: Looking for a *USEFUL* PROJECT book. Newsgroups: sci.electronics Keywords: So far, on ly JUNK. Summary: was projects; how about computerized design assistance References: <553@xroads.UUCP> I too learned much from reviewing, and occasionally building, the simple examples....learned lots of principles that way. Maybe we are just 10 years older, and those examples now are too simple. In recent years, after 10 years of "professional design experience" and [at that time] 4 years of studies of CS and AI, I earned an MS by developing an automatic circuit synthesis system, Dec 1986. LISP based, for several good reasons, capable of designing broadband bipolar amplifiers, AC coupled. We hit it with the task of generating an amplifier capable of interfacing between a phono input and a loudspeaker. It ignored the RIAA compensation since I had "told it {ACSS} nothing about RIAA", but the solution was a pretty good solution----given that push-pull buffers were not in the suite of diagrams/templates making up the knowledge base. The final stage transistor would have melted since was only a 2N2222, and the collector resistor would smoked; both those problems are easily corrected since the knowledge IF/THEN rules to upgrade the components are simple; I just had not expanded the spec/design/fail/analyze/change_spec behavior to handle single-point problems as trivial as substituting a much more powerful device [with the requisite increases in junction capacitance,etc]. The system, ACSS, currently performs amp design by satisfying the only overt constraint between cascaded stages, their Zin and Zout interaction. For previous design test cases, with R-source nominally that of R-load, 1 or more Common-emitter stages were the usual winners. For the power amp design we got an unusual selection of stages. In this case, R-source is 47K, R-load is 8 ohms, and a massive impedance matching is part of the problem. We also asked for an amp gain of 100. The winning design, after about 2 minutes of VAX11-780 time, had input stage Common-Base-gain&Common-Collector-buffer middle stage Common-Emitter-gain output stage Common-Base-gain&Common-Collector-buffer This was puzzling, but in a day or two, after reviewing the winning stage select heuristic, I realized the heart of this problem was not providing gain but matching to source and load. The several Common-Collector substages had provided that. AHHH ACSS was smarter than I had thought. (I had learned several other things about gain stages while "capturing the knowledge".) SO....automatic design EXISTS. For bipolar AC-coupled amps, not worried about noise floors or linearity,etc. Currently I am studying for qualifiers, but after March...what would be good domains to try [emphasis TRY] to add to the system? And in particular, what would be helpful to the lone home experimenter, trying to learn electronics? How much explanation is valuable, during the design behavior? and afterwards for credibility? and if someone different needs to significantly alter the design without assistance of the original designer [who is on honeymoon, or at a new job]? Allen Sullivan sullivan@asuvax.asu.edu [I think] sullivan!asuvax!asu!noao!nud [I think] ----> Side question...You wouldn't mind if I asked for a copy of this program now would you ??? -Mike -- ========================================================================== = Mike Carter !Xroads.wiz | S P Y T R O N I C S E N G I N E E R I N G = = N7GYX Phoenix AZ | "Imagine your worst nightmares as circuits" = ==========================================================================