kubuntu-users Digest, Vol 48, Issue 5

[Gene Heskett]

On Friday 02 January 2009, Brian Wootton wrote:
>> On Thursday 01 January 2009, Bruce Marshall wrote:
>>> On Thursday 01 January 2009, Steven Vollom wrote:
>>>> I will use alcohol unless you again reply.
>>>
>>> You might do better with a soft pencil eraser.
>>
>> No!  Not no, but hell no!  Dry, the eraser can and will generate local
>> static charges of several thousand volts, further damaging the memory. 
>> Simply exercising the memory out of the socket and back in should take
>> care of the problem if indeed that is it.
>>
>> My experience comes from nearly 60 of my 74 years, chasing electrons for a
>> living.  I am a C.E.T. since 1972, and a broadcast engineer since 1964,
>> and have been making a living fixing electronics since about 1949.
>>
>> Yeah, now I'm a genuine old fart. :) Almost retired for several years, CE
>> at WDTV-5 from 1984 to mid 2002, and my phone still rings when TSHTF. 
>> I'll likely never be more than 'almost' retired till I fall over for good.
>>  I have no intention of doing that, but I'm also diabetic, which says I'm
>> at a high risk.
>
>Oh dear, I've had disasters with cleaning fluids!

Yeah, when I started out in '49, the fav bit of panther piss for cleaning 
anything was methyl chloride.  I'm amazed some of us still have kidney's 
left.  Or brains.  Then later the fav was freon TF, the biggest joke DuPont 
ever foisted off on us.  Made the jerks rich, and we were fighting clogged 
heads on vcr's every 2-3 hours run time or less.  It took me 10 years to get 
smart though, and when I switched to plain old paint thinner alcohol as sold 
in qt cans at ACE Hdwe, the vcr head cleaning required dropped by 95+%!  From 
a couple of times a day to maybe once a week.

And sometimes one even has to use plain old tap water.  I recall one day, 
while the switcher playing a bicycled Flintstones tape on a 2" quad machine 
at a small station I was Chiefing at in NM, it dropped out at the 22 minute 
mark, we cleaned the head & and restarted it and it plugged on the exact same 
frame, 3 times.  We rolled a few commercials to fill the time and I did the 
clean thing again, but poised to hit the stop button the instant it failed.  
I spooled out a few feet of the tape to see if there was something on it, and 
found a dime sized spot of what looked like dried coca-cola on it, also on 
the back of the next wrap of tape.  Freon TF nor alcohol wouldn't touch it 
and you could plainly see where the heads had burnt their way across it, so I 
wet a qtip from the water cooler, and about 10 qtips later, plus a session 
with a hair dryer, also cleaned the head with water & dried it, the tape 
played fine.

A roll of that stuff was then about $400, and the dub charge about matched it.  
We had no money for such tomfoolery as we sometimes were late with payroll 
till Jim Bakker (of the infamous PTL Club) paid, which was never less than 6 
months late.  I sent a very hot letter to the syndicator and to the last 
station on the bicycle route.  It may even have self destructed en-route as I 
never got a reply from either.

But for a long time we hit those heads with freon and water just to get 
everything.  But make sure its bone dry before tape hits the head or you'll 
wreck everything.  That head was turning 14,400 rpm.

>and have fixed many 
>intermittent faults with a rubber,

So have I, but that was back when a tube could absorb a few watts extra grid 
dissipation or ttl based chip could take a few picoamps if current through 
the vbe junctions with no damage.  Today, almost everything is cmos, and 
forcing even one electron through the silicon dioxide that is the gate 
dielectric, something that takes less than 10 volts applied in many cases, 
will permanently change the characteristics of the device.  One simply cannot 
be too paranoid about static around cmos stuff.

>so I guess 
>you pays your money and takes your pick Bruce. I'm also 74 and diabetic
>but I haven't the steam left for any ding-dongs,

a common complaint for diabetics.  Even the pill isn't much help.. :(

>though I still use a soldering iron.

So do I, along with a dual trace 100mhz scope and a few other tools.

>brian



-- 
Cheers, Gene
"There are four boxes to be used in defense of liberty:
 soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author)
Only through hard work and perseverance can one truly suffer.