Well, a "good" electronics repair person should be able to fix anything. Basically, they don't want to be bothered.
The first thing I would do is check for voltage. Use the multi-meter on "DC voltage" setting. Check your AC adapter first, to make sure it's putting out the required 9V with the correct polarity (I think it's center pin = negative). DO NOT USE ANYTHING HIGHER! Next, plug it in and start checking the connections inside the unit to see where you have voltage and where you don't. OR, use battery power and do the same thing (= safer). Tracking down the voltage will probably lead you to the problem. Don't worry about testing the capacitors, resistors, etc. yet. You can't really test components properly unless you remove them from the circuit. No, you don't need a static mat.
If the power plug was the problem, it would most likely still work ok on batteries. Again, you test for voltage at the power plug contacts inside the unit, then follow the traces. If you're getting voltage in there, the plug connection is ok.
You may be able to use your 15W soldering iron. For small components like the transistor, you don't want much heat at all - too much will fry it. (The RCA cables you were trying to solder were probably much thicker wire and required more heat.) The other thing is, you want a small tip on the iron to do fine work. Ideally, you want an adjustable temperature Solder Station with an iron that has a variety of replaceable tips. I have the Weller WES51 (<
http://www.amazon.com/Weller-WES51-Analog-Soldering-Station/dp/B000BRC2XU>). Pricey, but again, it depends on how much you plan on using it in the future. This puppy will last a lifetime. There are many, many shapes and sizes of tips available for it.
I also recommend an Edysn Soldapullt for de-soldering work: <
http://www.edsyn.com/index.php?Mode=piw&pn=DS017>. Another GREAT tool.
As far as WHERE my burnt transistor was... unfortunately, it's been a while since I had my HT6000 apart, and I'm not able do do it again right now... BUT, I did write up a little something when I did it. Here's what I have (see below). I don't remember if I actually took any photos or not, but I'll look around and see. Hope this is somewhat helpful:
CASIO HT6000 Disassembly
Looking down into the
bottom of the Keyboard, keys away from you, "Casio" logo facing you
but upside down:
1. Remove all
of the screws in the bottom piece.
Before removing the bottom completely from the keyboard, you'll need to
unsolder the white-sleeved ground wire from the board on the left, near the
screw, AND unsolder the 2 white-sleeved battery wires from the board on the
right - Left is RED, Right is BLACK.
Remove the zip tie through the hole in the board securing the wires.
You'll also
need to unscrew the Card Reader, so it's loose.
2. Disconnect
the gray ribbon cable connector from the left side of the left top board. Remember, or write down, how the cable runs
underneath, so you can put it back correctly.
Remove the
6 screws in the right board - Mark or remember that the larger one goes into
the plastic riser post.
Remove the
6 screws in the left board - Mark or remember that the 3 larger ones go into
the plastic riser posts.
Move the 2
top boards out of the way.
3. Unscrew and
move the 3 Keyswitch boards out of the way:
There are 12 screws in the left board, 6 screws in the middle board, and
10 screws in the right board. Remove
them all.
4. Remove the 9
screws in the 'Output board' and move it out of the way.
5. Remove the 5
screws thru the 'Foil board,' which is covering the 'Power board,' and remove
the 'Foil board'.
6. Remove the
remaining 6 screws in the 'Power board'.
There are slider controls that go thru the keyboard body on the left
side - remove those knobs, and then you can lift up the 'Power board'.
7. The
transistor which burned out on mine is on the right-side of the board. It's a very small black vertical rectangular
piece with 3 legs (connections). It says
"B1117" on it. The board was
black all around it in a circular pattern where the heat burned it.
Good luck! Let me know if you need more help. If you send photos of your progress, maybe I can help guide you.
-Tom
