"Retro Repair" key electronics skills?

In order to trouble shoot, one needs to know how it is suppose to work. This often means studying schematics, data sheets and sometimes even app-notes. Avoid the replacing everything, until it starts working, type trouble shooting. As well as being a waste of time, it is more likely that you will introduce new problems in the process. Don't replace a part unless you can prove it to yourself that it is the most likely source of the error. This usually means running experiments. Since you are a coder, I find that anything with a working processor can be used as a self debugging tool. EPROMs or front panels are great for trouble shooting. Simple test are best. Many fear power supplies. Linears are the easiest because they are always some form of feedback loop. You just follow the loop until you find two points that are opposite directions from where the input point predicts the output point should be( goes back to knowing how it should work). If you can't find a schematic on the web, draw one. As a minimum, have a block diagram. I'm sure you have heard of the "scientific method". Trouble shooting is just that. It is the repetitive process of making an educated guess as to the source of the problem and then having an experiment to prove it either true or false. Try to have experiments that are conclusive. This is why I don't much care for the piggy back RAM test. It may or may not tell you that there is a problem with the RAM that you are checking. Learn to use a two channel oscilloscope with trigger and delayed sweep. Dwight ________________________________________ From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Swift Griggs <swiftgriggs at gmail.com> Sent: Tuesday, May 10, 2016 1:03:44 PM To: General Discussion: On-Topic and Off-Topic Posts Subject: RE: "Retro Repair" key electronics skills? On Tue, 10 May 2016, tony duell wrote: It seems like there is a lot of "fiddling" with those types issues and getting good at doing so is part of the process of getting profecient with component level troubleshooting. That's why working with electronics "kits" (ie.. kit based projects) is about my speed right now. In most of those cases, folks have worked out the kinks involving connection issues, but I'm still just doing analog stuff. I have no idea how much it'll matter when I go to learn a bit about digital. However, that quote about digital circuits being made from analog physical bits seems like good foreshadowing. So, we'll see. I'm still playing along with projects from a kids' Elenco kit. I'm having fun with timers and making "bleeps and bloops". I'm also using it to try and figure out how about 5% of my borrowed ocilliscope works. I've got the manual, it's just figuring out what everything means is a bit challenging right now. So, it helps teach me how to calibrate the darn thing to just sit on something that looks like a sine wave etc... -Swift