Excellent ploint, Jack. I've often used that calculation to determine whether to do something myself or hire a service company (giving the bathroom a good cleaning is a good example). But repairs to an applicance come with an additional consideration. Fixing a dishwasher or dryer means I don't have to send this big lump of stuff to a landfill.
Radio Shack is okay for 10% resistors and a few transistors, but I find that I often need capacitors rated for the military temperature range, for use in the outdoor heat-pump or under the car hood. Radio Shack only stocks commercial grade capacitors, not military grade, even though the military grade units cost only a few cents more.
Radio Shack was a good place to go, but you had to give them your phone number and address every time you bought something in the store. Now, Amazon.com actually has a good supply with no ship minimums.
Excellent analysis Rob and Kf2qd. However, whenever I'm in similar discussions that one thing that is asked is "And how long did that take you?", which is often followed by "Well, if you make $xx an hour at your job, along with all your benefits...and my free time is worth more to me than that!"
Larry: The "problem" with your logic of checking inside and replacing defective components is that you are denying the refuse collection technicians (garbage men) there right to make a decent living by picking up all this "junk". Furthermore, the landfills would not be nearly as filled, since a picofuse or SMT transistor occupies far less space than an entire stereo system. And, IF that's not enough to spur your patriotic juices, how about all those Chinese assembly line workers that could be furloughed because YOU did not purchase a new $500 stereo ...... instead replaced a 37 cent part??????
I think young people are apt to replace a product rather than fix it for a number of reasons. They've been taught by brand owner to replace rather than repair. Most kids don't know how to replace the battery in an iPod. When the battery goes, it has to be replaced. By the time a TV goes, the consumer is so far behind on features, there is no reason to repair the old TV. In fact, TVs are getting replaced before they go bad because of the new features.
Back in the day, with Sams Photofacts and MCM Electronics there was nothing you couldn't fix.
I've gone through a series of preferred sources over the last 50 or 55 years, as each one gets "commercial focus" and establishes minimum order levels too high for hobbyists. Allied and Newark were great when I was a kid, but now the $50 or $100 order makes them unfeasible sources for a couple of transistors or capacitors. My current favorite is Mouser.
Waah. It was a professional development learning experience. The company benefits from this type of learning of its professional staff. You ought to see what constitutes work for executives when they have their corporate retreats.
In our throw away society there are many products out there that are discarded for want of a $2.00 part. I have a background as a Machinist as well as in Electrical technology and find that many times some simple, impossible to fid part is the only problem. Fortunately I can go out in the shop and use my small lathe and mill to make a replacement part. It might take me several hours and would seem to not be cost effective, but when I have some time and no money that part I am able to make is a real life saver. Just think how much money is spent because almost no-one anymore has any idea how things work, and thus they don't know that it could be repaired.
A $150 repair avoided to a television for a board that I was able to obtain for $25, deliverred. The thrown away lawn mower that I was able to fix for $12 worth of parts after cleaning the carbon out of the cylinder and installing a new air filter.
And we have a generation that are growing up now that have never taken anything apart and put it back together. Hand them a screwdriver and they stab themselves, a wrench and they smash their finger... And they say wonderful things like "You fixed that? I just threw mine away and got a new one..." And then they wonder why they owe so much on their credit card.
For industrial control applications, or even a simple assembly line, that machine can go almost 24/7 without a break. But what happens when the task is a little more complex? That’s where the “smart” machine would come in. The smart machine is one that has some simple (or complex in some cases) processing capability to be able to adapt to changing conditions. Such machines are suited for a host of applications, including automotive, aerospace, defense, medical, computers and electronics, telecommunications, consumer goods, and so on. This discussion will examine what’s possible with smart machines, and what tradeoffs need to be made to implement such a solution.