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Strange switches and electrons

This is just a question for curiosity.

I have a Magnavox 12 or 14" CRT tv with built-in VCR. I guess that means it's about 20? years old. Maybe it's generation can be judged by the fact it also gives the choice of English or Spanish when first plugged in.

I don't have the remote.

Often, when I push the Volume Down button, instead it lowers the channel, from 3 to AV. I think the on-screen volume display disappears then, so I use Channel Up to go back to channel 3, and then again try Volume Down, with the same result.

If I hold Volume Up for a while, Volume Down usually works, so this is not a major problem, but how is this problem possible?

Is this related: I have a Huaweii (sp?) smart phone that I dropped from 2 or 3 feet on to a ceramic tile floor. After that, when the phone is turned on, instead of the AT&T logo that used to show first, instead the first screen is all green background, with one big red and one big blue rectangle on it. But the next logo shows up and it starts and every feature that I try to use works. What happened? Did I bounce some electrons around.

Reply to
Micky
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Don't know about the phone except to say the logo thing is an overlay like the boot screen on a computer - you're quite lucky nothing else got broken.

On the TV, assuming you are talking about the buttons on the TV - I would say the tact switch underneath the button is defective, essentially changing the value of the resistor network of which it is a part. I've seen this type of problem often on tv's. The switch would have to be replaced.

Mark Z.

Reply to
Mark Zacharias

Yeah, I think it's amazing that I broke only that. All this stuff is hard-coded in some ROM, right, and yet hitting the floor could change a byte or more, but not screw up the rest.

Very interesting. So if anything it will likely get worse.

I used to use a remote, but I stopped using this TV for a couple years and the batteries died. I will fix up another universal remote, and I gather that will by pass the bad switch. I have other 14" crt tvs, that people throw away, but this one has a built-in VCR, which I like even though in 5 years I've never used it.

Thanks a lot.

Reply to
Micky

Yeah - remote control operation wouldn't normally be affected.

mz

Reply to
Mark Zacharias

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