On Sun, 24 Jun 2012, Tony Duell wrote:
OK, but be warned you might not like my answers :-).
Nor mine. For that matter, Tony won't like my answers, either :-)
Maybe NOBODY will like the suggestions that I'm making off the top of my
head, . . .
The first tool for you to buy is a DISPOSABLE multimeter.
You WILL buy a better one. LATER. When you have a clue what it is and
can do, have learned what can damage it, and have learned what aspects of
the cheap one are intolerable. YES, there are dome aspects of that cheap
one that are HORRIBLE! THIS one is only for learning about
Go to Harbor Freight Tools or online at harborfreight.com
The list price is $9.95 , but they are often on sale in their retail
stores for $3.99, $2.99, or free with a coupon!
Take apart one of their $1 or free with coupon flashlights.
How many things can you measure of it?
What happens if you use the wrong scale, or get it backwards?
measure everything else within reach!
Keep YOURSELF clear of everything! Killing yourself while measuring a
mains outlet could set you back!
WHEN you blow up the meter, go get another one, and remember what you did,
so that you won't ever do THAT again.
NOW, for the big moment, . . .
measure all of the voltages of the C64 power supply! (a likely cause of
the problems, anyway!) Look up what each voltage is supposed to be, and
decide whether they are close enough.
Even bigger excitement, . . .
Open the case! Find where ground is, and where it is supposed to be.
Now find where voltage (typically 5V DC) is supposed to be. Measure it
EVERYWHERE that it is supposed to be, including the power input pin of
every chip. Studying the "pinout" of chips to find out which one that is
supposed to be is one of your first "research" assignments. (HINT: it will
be the same on MOST of the chips)
Do NOT touch anything in the power supply of a computer until you get to
the point of knowing what can or can't bite or kill you. Most of us have
been thrown across a room now and then - best not to duplicate all of our
Buy a cheap soldering iron, and some 60/40 rosin core lead solder. ($5)
You WILL buy a better one LATER. In fact, you will NEVER use this POS
one on ANYTHING that you want to keep!
Take a stack of SCRAP boards, that are irreparable and useless (you said
that your friend had destroyed some, . . . )
Unsolder a large resistor from one of the boards. Unsolder another one.
Solder them back on. remove EVERY component from the board. Put every
one back on. How many did you get backwards? How many did you destroy?
Once you've soldered and desoldered everything on a few boards, Start
planning to buy a REAL ("temperature controlled") soldering iron. (try
flea markets, eBay, etc.) You might find the POS one to be useful for
rewiring lamps and toasters, etc., but once you've used a REAL soldering
iron, you'll never want to touch the POS again.
Get a better screwdriver for taking apart your computers. A cheap one
with 1/4" bits will do until you understand WHY you need a better one.
Learn resistor color codes. Do you know what an ohm is? farad?
"If your car headlight draws 10 amps, how many watts is it?"
Read a few basic electronics books. Used textbooks from the local
community college, perhaps? Maybe even TAKE some of those classes!
"Art of Electronics" by Horowitz is GREAT, but it costs money.
Got relatives who XMAS shop?
Buy some kits and assemble them. Now get them to WORK.
Watch for deals on cheap (used) logic probes and even [oscillo]scopes.
Even a POS scope is fun to play with (what does the speaker signal of your
hi-fi look like?, if you put the left channel on the X axis, and right
channel on the Y axis, what do you get?) and to learn how to use one, and
to learn what you want to get when you invest in a "REAL" one.
Get all of the technical documents for all of the machines that you want
to work on, or are even just curious about
Read up on the start-up process for computers, particularly the ones that
you want to work on. "How can you tell whether the microprocessor is
Have you learned enough about your cheap tools to know what to look for,
and what YOU want, in some decent tools?
Fix the computers.
If you got this far, you've almost certainly abandoned these "silly
steps", and have taken off on more interesting projects and tangents.