Many decades ago I worked alonside another engineer who, in a previous employ, broke into the field of electronic engineering at the old SYLVANIA TV factory. This was in the days of hard-wired & minimal p.c. board-equipped products. One of his first assignments was to take a working TV, which others had designed & proven, and remove components w/ a wire-cutting pliers. Part of this task was to document the degradation of signal, video, audio, etc. At the point at which the TV was deemed circuit unstable, that was his end point. The purpose? To shave as much off the B.O.M. as possible, yet maintain a saleable product.
Although he never mentioned the outfall, I'm sure his fellow engineers in the original design dept. weren't too thrilled with his assignment.
OLD_CURMUDGEON, I'm with you. In fact, at my house we're no longer throwing away old appliances but getting them fixed or fixing them ourselves. The growing stream of new junk, I mean products, that doesn't work is incredible.
Battar, thanks for the clarification. That's interesting about damage during assembly, since so many others' comments mention poor design, which is what I've experienced. It's also not too surprising that the keypads you're using are more expensive, and better, components. Just because an appliance is low end doesn't mean it has to have components that fail quickly. I'd be happy to pay more for the option.
Ann, the keypads we use are not particulalry cheap, but they are designed for an outdoor environment. We do individually test each membrane after assembly in the product, and we do have rejects. There have also been a few returns with contact related problems, so I won't say they are all perfect, but from my experience they are more reliable than mechanical switches. I think the problems mentioned by the readers relate to ultra-cheap components, and insufficient quality control.
If Battar's company uses a membrane keypad that actually works, and DougieSellers' company makes such keypads, then why aren't these used by all the appliance manufacturers? Are there really that many different ways to design membrane keypads that work, vs ones that don't?
Battar, I won't throw tomatoes at you--but I simply can't agree with this statement, based on my experience and the majority of people who comment on the subject in this and several other posts: "Membrane keypads usually fail at the time they are installed in the product." They commonly fail after a certain period of use, which is always much shorter than the life of the appliance.
I dont like to provide free advertising, but you did ask, so I will answer. Sangean is a far-east manufacturer of radios, including the type you are looking for and can't find. You might find what you are looking for in their catalog - I did.
We have a Maytag /whilpool dishwasher and at three years old the membrane panel is starting to peel, which is a poor reflection on the quality indeed. I replaced a similar, but older, dishwasher for a customer, (their decision), because the cost of the replacement switch was about a third of what they had paid for it six years earlier.
What was interesting is that ohmmeter tests showed that the contacts were indeed unreliable, which, even if it were used every day for six years, is only 2190 operations, which should not wear out a switch.When the membrane panel in my home unit fails I will replace the membrane buttons with small mechanical buttons, which, even for mil-spec buttons, will be cheaper than a replacement panel.
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