:: Re: [DNG] OT: Digital replacement o…
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Lähettäjä: Bruce Perens
Päiväys:  
Vastaanottaja: Steve Litt
Kopio: dng
Aihe: Re: [DNG] OT: Digital replacement of mechanical mechanisms
My son gave me a ride in what had been my 2007 Prius until I gave it to
him. It probably has a lot more than 150K miles by now, but I'll have to
check. It had a bad pump once and the dealer shop replaced it for free.
Thieves took the 15-year-old catalytic converter, which the insurance
company took care of. Then we had a 1" steel cable welded from the new one
to the frame. I've had to change the 12-volt battery once (it's smaller
than a normal car battery) and do the routine maintenance.

The NiMh battery in the Prius is still fine. It was driven up and down
steep hills longer than the battery range, every day.

My 2015 Jeep Grand Cherokee is doing fine as well at 60K miles. It's driven
off road to my off grid site and pulls a trailer. Never had a mechanical
problem. I put in a Chinese 10" display radio that runs Android and
interfaces to the internal controls properly.

My 1990 Toyota Camry was driven until 2007 when the rubber engine mounts
failed. There were no mechanical issues until then. I donated the car, and
it was repaired and kept driving for a long time afterward. I knew because
I stupidly left my ham radio callsign plates on it when I donated it,
expecting the shop to turn them in rather than give them to the new owner,
who drove around with my callsign for many years.

I guess that buying some american sedan brands can be worse.

An Integrated Circuit with a billion transistors does not have a shorter
lifetime than a single transistor.

There is, however, a component that does have a short lifetime. The
electrolytic capacitor. You can buy ones with longer or shorter lifetimes,
but eventually they need to be replaced. However, not everything needs to
use them. I have a lot of 1980's test equipment and have had to replace
some. And also that Dallas chip with an embedded battery that Tektronix
used for parameter memory and date/time clocks.

I agree that there are high prices charged for some electronic modules
because they are only serviced at the module level. I do surface-mount
soldering and rework, but it's not really worthwhile at scale. We could
repair tube and through-hole electronics when the technician salaries were
much less than today. These days there is better work for that sort of
person than a repair shop.

    Bruce



On Wed, Jun 21, 2023 at 5:44 PM Steve Litt <slitt@???>
wrote:

> Hi all,
>
> At the dawn of digital control of things (late 1970's, early-mid 1980's,
> I was an audio repair technician. Before then, cassette decks were a
> Rube Goldberg mess of gears, levers, springs, pawls, and who knows what
> else, every one of which could bend, break or wear. You haven't lived
> til you repaired a 1970's Akai cassette deck. It took an hour to
> reassemble, with springs flying all over the place. Back in those days,
> you had to press the "stop" button before transitioning between any of
> play, fast forward, or reverse, or else you'd screw up your tape.
>
> Then they introduced 4 or 8 bit microprocessor systems to control a few
> relays to move heads and turn motors, resulting in a much simpler
> system on which pressing buttons in the wrong order did no harm because
> the microprocessor listened to your button input and "did the right
> thing". Technicians and teachers alike heralded the dawn of processor
> driven machinery, because an 8080 plus a couple transistors to pull
> solenoids were much more reliable than mechanics that could bend or
> relays that invariably went bad.
>
> A transistor had a much longer mean
> time to failure than a lever, spring, pulley, belt or relay. What they
> didn't say is that the sum of a million transistors had a much shorter
> mean time to failure than any lever, spring, pulley, belt or relay.
> Today's i9 processors have 4 BILLION transistors. Ugh!
>
> When you buy a car, one of the ways they upsell you is to say that your
> car's cockpit computer system will be the first thing to go, and that
> will be very costly. Yeah, it's nice that today's cars are made with
> enough precision that your engine and transmission can last 200K miles
> with proper standard maintenance. But the computer systems, the most
> difficult things to diagnose and expensive to replace, will go bad in
> 30-60K miles.
>
> When we were getting our third in-wall Microwave oven replacement, I
> mentioned that I'd like it to last as long as our counter microwave
> that we'd bought for $55 in 2004. The tech laughed and said modern
> stuff doesn't last like the old appliances. A little further inquiry
> laid the fault squarely on the massive computerization. Same with
> refrigerators: My wife bought a 1990's fridge second had in the early
> 00's, and that fridge lasted through three brand new kitchen fridges.
> Don't get me started on air conditioners with their $600.00 thermostats
> and $500.00 circuit boards with interfaces so daunting that the tech
> who comes to your house must phone a specialist. I mean really, all you
> need is an analog thermostat with one or two thermocouples, connected
> to a couple relays or triacs in the air handler and condenser. But
> nooooo!
>
> It's a good thing that smart phones obsolete yearly, because I bet they
> wouldn't last much longer than two years. About 4 years ago the last of
> the fully mechanical washing machines were phased out. My momma didn't
> raise no fool: I bought one before they were gone, and when it breaks,
> I'll pay more than its purchase price to get it repaired, and you know
> what, if the parts aren't available they can be substituted or whatever.
>
> You know what's really annoying? Most of this digitization isn't even
> for essentials: It's for cutesy stuff like interfacing your radio, horn
> and alarm system together (so it's hard to troubleshoot any of the
> three). On a microwave, much of the digitization is so the human can
> push the "pop corn", melt butter, or defrost button instead of just
> selecting a heat and time. Useless!
>
> And this BS spills over into computers people use. Much of the software
> written today has nothing to do with calculating dollars and cents or
> angles, internationalization, security, 3d printing, or even games. How
> much software is sacrificed at the alter of "user friendly" where "user
> friendly" means automatic boot up to X, transparency, various
> components of "pretty", drag and drop that's completely different on
> every type of user interface, guessing what the user wants instead of
> giving the user a menu, and all sorts of other geegaws. Let's not
> forget the million plus line of code systemd, or the resource-sucking
> KDE and Gnome.
>
> I was around in the 1980's. I saw perfectly normal people use command
> line MS-DOS and WordPerfect with great productivity. I saw secretaries
> troubleshoot printer problems. In about 1986 I saw an 8 bit CPM
> Osbourne computer that came with a multilevel menu, and I saw
> WordPerfect's menu program make everyone's life easy on DOS. Even Win95
> came with a great menu system. We could have raised the population's IQ
> with menu interfaces and some documentation, but instead we chose
> gigantically complexify things in the name of "the ordinary user", and
> in the process relegated logical thinkers to decreased productivity.
> Why???
>
> Appliances, cars, air conditioning, audio equipment computers. Why?
> Here's why...
>
> Follow the money!
>
> SteveT
>
> Steve Litt
> Autumn 2022 featured book: Thriving in Tough Times
> http://www.troubleshooters.com/bookstore/thrive.htm
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--
Bruce Perens K6BP