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 Just because I don't wear Earth Day or "Save
the Whales" T-shirts or donate to their causes does not mean that I abide wanton
and senseless destruction of our planet's resources and natural beauty. Do a search
of RF Cafe and you will find many examples of articles I have written and headlines
posted regarding offenders and, equally as important, the hypocrisy of many people
and groups who are in your face constantly about these issues. Most of those types
are either woefully stupid about and ignorant of how their actions are hypocritical,
or are in it for the money and/or notoriety and don't care about their hypocrisy.
The former join protests in opposition of petroleum companies while wearing clothes
and owning devices manufactured in part from petroleum products, or made in factories
whose machinery incorporated such materials. They conveniently ignore the petroleum
products consumed in transporting themselves and their consumables from point A
to point B. The latter, like a particular former VP, make multiple millions of dollars
demonizing petroleum while gluttonously consuming it themselves.
My approach is to be personally aware of
and responsible for causing as little damage to the environment as possible while
availing myself of a reasonable amount of modern conveniences. One way I do that
is to repair, renovate, and repurpose many things ranging from houses to appliances.
Melanie and I have renovated no fewer than half a dozen houses
(while living in them) in the last 30 years. We have
not purchased a lot of excess stuff over time, and nearly always donate things we
don't need anymore rather than sell or throw it away. I feel no guilt.
 My latest example of repair is a
Braun kitchen hand mixer that we've had for at least two decades.
The blue heat shrink tubing on the power cord was part of a repair done many years
ago. Recently, Melanie reported that the multi-speed switch seemed to be intermittent.
After confirming the symptom, I opened the case and removed the switch assembly.
Fortunately, it was held together with locking tabs rather than glue. I popped it
open and found some of the contacts to be pitted and covered with arcing residue.
I reconditioned the contacts, cleaned everything, and snapped the switch case back
together. So confident was I of the repair that I even reassembled the entire mixer.
I plugged it in and now it didn't work at all! A major deflation of ego accompanied
the failure.
Thereupon, I took it apart again and verified the switch positions with a multimeter.
Everything was AOK. In the process, I noticed that one of the motor control transistor
leads was broken (see lower photo). It doesn't get much more obvious than that.
Fortunately, the portion of the lead soldered to the PCB had a lot of extra length
so it was possible to heat the joint and pull enough through to mate sufficiently
with the part of the lead on the transistor package. A little emery cloth, a little
flux, a little heat, and a little solder (PbSn -- OMG, I am
an eco terrorist after all!) did the trick. Daunted by my aforementioned failing
of technical prowess, this time I plugged the mixer in and tested it prior to putting
everything back together. It worked perfectly.
My guess is that over time, this heavily used mixer was banged around enough
to cause a fatigue failure in the lead, no doubt assisted by the fact that the heat
sink is not supported, adding an extra measure of force to the transistor frame
with each impact. I am somewhat ashamed to admit that I did not take advantage of
the opportunity to properly secure it. I'll do it next time.
Interestingly, about 10 years ago Melanie's big countertop
Mixmaster (Sunbeam) stopped working. The motor control transistor
had fried on it, and at the time I was actually able to buy a replacement at the
local Radio Shack. I doubt they even stock such a selection of devices anymore,
although there is still a lot available online. In fact, very recently I bought
a couple 10 W wirewound resistors from Radio Shack online; they had the best
price for what I needed.
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