distar97 wrote:
Hi guys...
I've noticed over the years some of my consumer electronic items are
going way beyond what might be considered a normal life span. I've
seen recent threads about bad caps in computers, malfunctioning
microwave displays etc. that make me wonder about component design and
the other things that affect a products life, specifically usage
patterns.
My good example is my JVC model# 3070 a 2-1/2" portable B&W TV. I got
it in 1975. Since I'm nearsighted, I use it to watch late-night TV
while it sits on my night table. The picture is like new and very
sharp, as small b&w CRT's can be. I keep the brightness turned down a
bit to reduce stress on the system. It frequently stays on after I fall
asleep.
So it is on from 2-8 hours a day, nearly every day for 30 years. My
question is, do you think the components are lasting this long because
they are used every day as opposed to infrequent use? What if the same
TV sat in storage for years, rarely used, would the caps fail sooner? I
guess I'll find out, I found the same model on ebay, I'm keeping it in
storage as a backup.
Dennis Harper/Bronxville NY
I think charging up electrolytic capacitors for at least a few minutes every
six months or so will tend to prolong their life because it re-grows the
insulating layer inside the capacitor, or in other words, if you were to
let the TV stay off for 10 years and then try to use it, there would be a
risk that some of the caps would have become leaky and might even overheat
or burst.
On the other hand, leaving the TV on all day could shorten the life of the
electrolytics if they run fairly warm, and would be certain to make the
tube lose some emission.
I am in favour of switching things off when they are not being used because
of the pollution / intractable waste caused by the normal means of power
generation.
I think that your TV might be lasting well because it was made at a time
when people really cared about how to build a good CRT TV. I think that
each appliance has a 'golden age' when the profit margins are still good
enough that it's worth putting good engineers on the project, the
components are new enough that engineers are taught how they work, and the
appliance is still expensive enough to be worth making it repairable, but
after the initial bugs with the basic technology have been sorted out.
Once the item becomes regarded as a disposable commodity, they don't try to
compete on good design or quality any more. Therefore a cassette walkman
from the early '80s or a VCR from the late '80s will be far better made and
even better performing than what you can get now.
Chris