I am finally taking the time to again cull through my collection of model train magazines. I did this some 25 years ago and am finding that amongst those I saved, only 1/3 of them are still of interest. I've always enjoyed tinkering with electronics and am amused at the number of circuit corrections I find in these magazines, where a month or two later I read that components were omitted or misplaced in the schematic. Back when these issues were new, I soon learned to never build a circuit until several months had passed and mistakes were exposed with revisions published.
Yes, I remember seeing quite a few corrections, too. The one I remember most is the one where they had the frog of a switch drawn in a diagram backwards. Doug
I have seen that as well, not just in MR magazines, but also in the old Electronics Illustrated / Popular Electronics magazines. Makes me wonder if they had ever actually built the circuit from their own schematics before publishing it.
The schematics may have been re-drawn for publication (in a form factor to suit publication), and the errors made in doing so.
so much for proof reading huh . this is prob exactly what happens. schematics have been drawn correctly but then the writer screws up ....
No doubt the user may have also tweaked the design to get it working, and may not have updated their own schematic either. If the publisher redrew the schematic, I'd be surprised if the author/originator was not asked to verify it. Humans make mistakes (including in the machines they make and the computers they program). A long time ago at work, I wrote a program that would compare two netlists only by reference designators and pin numbers (not using signal names), so that I could confirm that two large schematics (one redrawn on a new schematic capture system) were equivalent. Of course it required both schematics be drawn in schematic capture applications, which is probably not what a publisher would use (if even the designer, back in the day).
Then, of course, you have the magazine graphics people who may decide they can make the schematic "sketch" more presentable for publication. "I don't think it makes any difference which way that triangle points, there. Just point it that way." Just like photographers who almost invariably get one or more wheels off the track or tender sitting backward behind the locomotive. Doug
It happens in industry all the time too. I used to run the machine shop in a factory building garbage trucks (dumpster trucks ???) and made the necessary corrections to parts and hydraulic components design as the drawings came through. I sent the corrections back to the engineer ..............buuuuuuuuuuuut ........... he had a bit of a superiority complex so he never changed the specifications. I had the drawings carefully saved in the machine shop. Everything worked. After 7 years I left , and the new guy threw out all the "junk" I had amassed. Guess what happens next !
