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Re: Is it possible to install Debian in such a case.



On Friday 28 June 2019 02:14:42 deloptes wrote:

> Gene Heskett wrote:
> > There was a period a decade back where the capacitors
> > were legendarily bad.  Your unit may have some of them in it.
>
> It was around 2004. From a trustful source I understood that the
> Chinese manage to steal the formula from Japan, but translated few
> things wrongly and the world was flooded with bad caps. In the company
> I was in back then, PC caught often even fire. We had to mitigate the
> risk or just replace the PC with more reliable once. This was a good
> story.

I think your beginning date is likely right, but it took a looong time 
for those to get flushed out of the supply pipelines. They typically 
went for 10% of what the good stuff was worth and a lot of buyers with a 
BOM in hand thought they were getting a good deal.

Electrolytic capacitors are a very old tech. I even caused a shortage of 
American made caps in the middle of the OPEC battle in the '70's.  I was 
at the time a tx supervisor for Nebraska ETV, in charge of a channel 19 
site NE of Norfolk NE, getting pretty close to colder weather and 
needing a barrel of Technical Grade Ethylene Glycol for making a 30% mix 
for transmitter coolant.  As that was a klystron using transmitter, you 
had to have extremely pure, as in distilled or better coolants else the 
voltages involved would corrode the plumbing very quickly from galvanic 
effects.  Anyway I ran up quite a phone bill locating a barrel, finally 
finding it sitting on a shipping dock in Omaha, and bought it on the 
spot, paying about $14/gallon. I had antifreeze for the winter, but that 
barrel was the last in the country, and was scheduled to be shipped to 
Sprague in Lincoln about 3 weeks after I bought it off the dock.  Put 
Sprague out of the cap business for several months and created a 
nationwide shortage of replacement capacitors for the tv's etc of the 
day. It was well into the next summer before caps started showing up in 
the wholesalers shelves again.

That rise in energy costs broke a few broadcasters and sounded the death 
knell of klystron amplifiers. It did take something over a decade to 
flush them, the last time I was one was in 87 or 88, when I was coerced 
into going up the WNPB, near Morgantown, one of the State of WV's 
educational tv stations, to see if I could get them back on the air. 

Poor operator education caused them to wreck one, and they had no real 
money to buy a new one at $130,000 or so from Varian.  But this was late 
April or early May, and the legislature had included money for a new 
transmitter, available after 1 July.  So they bought a used one that was 
full of air, then another used one that might have been usable had the 
half moons in the shipping crate been reinstalled.  But they weren't, so 
I unpacked it, checked for gas, found very little so it seemed worth 
dressing it up with its cavities, setting it in the magnet dolly and 
trying.  It wasn't until I was trying to seat it in the dolly that I 
found it was bent. At that point all the state engineers declared it 
would not work. But I thought we had one chance, and by then I was 
convinced I was the only one in the building who actually knew how the 
darned things worked.  So I scouted around and found some masonite and 
cut a couple pads out that could be wedged between the magnet coils and 
the corners of the top cavity, and placed them such that the tube was 
centered in the coils again.

Measureing for  center, I placed the iron places called wobble plates 
back on top of the dolly and wheeled it into the cubicle & hooked up the 
plumbing. Then I set the supply feed to Y which cut the beam voltage to 
about 10K volts, and raised the accel voltage as high negative as it 
would go, said a small prayer and brought up beam power. Body current 
was high so I had a limited time to see if moving the wobble plate would 
reduce it to a tolerable level, and it did.  Then I lowered the accel 
toward ground, wash, rinse, repeat. Put the beam supply back in delta 
mode, wash rinse and repeat. About that time I became aware that the 
beam was catching the gas ions and was carrying them to the collector 
bucket and probably burying them in the copper. Any way, a few minor 
tweaks and a tube they only paid 10g's for used was on the air at 85% 
power and a safe and slowly falling body current.  And the other state 
engineers finally understood they had been watching someone who knew 
what he was doing. And while I was by then tired, it was about a day 
before the grin let my ears come back to their normal position. I spent 
far more time teaching the young operators as they came on duty how to 
keep it adjusted than I did trying to teach the engineers observing me 
being a nerd. After all, they'd been to school, had sheepskins on the 
wall. I've an 8th grade education, but have never stopped learning.  
They had.

Cheers, Gene Heskett
-- 
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
If we desire respect for the law, we must first make the law respectable.
 - Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/gene>


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