Corrosion repair on an Embryon

willymotts

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I got Ed's kit. At C13 there is a .01uF axial capacitor. The one that came out has the following markings: blue/blue/orange/black/brown. I have no replacement piece with these same markings. This thing looks just like a resistor to me but the info says it's a cap. It says "part marking = 103". I'm sure that is supposed to tell me what cap to use but I was never good at riddles. Pardon my ignorance and I appreciate any and all help I get.
 
You're reading it backwards. brown/black/orange = 1/0/3. I'm not sure what the blue/blue is for. I'd say volts and tolerance, but I'll have to read up on it.

[EDIT]
Ok, it turns out that there are somewhere close to 42 color code styles for caps, none of which match up with what you have. I guess my tech-fu is weak, so you'll have to measure it. :)

[ANOTHER EDIT]
Ah-hah! This looks promising. (see the attached picture) Those axials are weird, with their own code.
A = 1st digit (same code as a resistor)
B = 2nd digit (same code as a resistor)
C = multiplier (here it gets weird)
D = tolerance (weird)
E = I think this is temp coefficient

Based on gaps in the table I found, I think your decoding goes like this:
BL - E = -470 ppm/degree C
BL - A = 6
OR - B = 3
BK - C = 1
BR - D = +/- 1pf

=> 630pf, +/-1pf, -470 ppm/degree C

[LAST EDIT - I PROMISE!]
First I want to say 2 things.
1 - I hope I never hear another person complain about having to read resistor color codes.
2 - Capacitor codes suck. There is no standard. Even for the multiple "standards" each one may have changed over the years. Ugh. So here's the take away: don't trust anything I've written here. Because my sources contradict one another. And one contradicts itself.

Now, I finally found the 5-band code I was looking for. The one I was thinking of when I made my initial kneejerk post. According to it The bands are 2 digits, 1 multiplier, 1 tolerance, and one voltage. Looking at the picture again, you need to decide if the "E" band is blue or brown. If it's brown, then you have a 10000pf (0.01uF), 6%, 600V cap. If the "E" band is blue, then it's using a different code - neither tolerance nor voltage can have a black band.

Ugh. Sorry to get your hopes up. Measure it.
 

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I got Ed's kit. At C13 there is a .01uF axial capacitor. The one that came out has the following markings: blue/blue/orange/black/brown. I have no replacement piece with these same markings. This thing looks just like a resistor to me but the info says it's a cap. It says "part marking = 103". I'm sure that is supposed to tell me what cap to use but I was never good at riddles. Pardon my ignorance and I appreciate any and all help I get.

Your new caps are probably yellow (unless Ed has changed suppliers). A marking of 103 = .01uf. That resistor looking thing is a cap. Find a cap in the kit with 103 stamped on it....replace the resistor looking cap with it...done.

Edward
 
Your new caps are probably yellow (unless Ed has changed suppliers). A marking of 103 = .01uf. That resistor looking thing is a cap. Find a cap in the kit with 103 stamped on it....replace the resistor looking cap with it...done.

Edward

The problem with standard capacitor color bands is that each manufacturer had their own standard. Tough to tell wht the original cap's coding was without knowing who made the cap.
Regardless - what you want for C13 is a 0.01uF. As Edward stated - you want the one marked "103". These are Kemet C410 series caps, nNo worrying about reading the color bands when the value is printed on the cap.

Ed
 
I misuderstood. I thought the instructions were telling you that the old cap was marked 103. If it's the new one then yeah, just yank and replace as instructed.
 
Yeah. I guess my old eyes just are not what they used to be. I did find 103 with a good deal of help from some reading glasses and a really good magnifying glass. Thanks to all who tried to help me with this. I have never run into caps like these and I got all befuddled.
 
Yeah. I guess my old eyes just are not what they used to be. I did find 103 with a good deal of help from some reading glasses and a really good magnifying glass. Thanks to all who tried to help me with this. I have never run into caps like these and I got all befuddled.

I can never read those things without a damn magnifying glass :)

Edward
 
I repaired the corrosion effected parts from the battery damage. Now, I get two coils locking on when I power up. I reflowed all the pins on the solenoid driver as there were some cold joints but no change. I'm willing to admit defeat and buy a new main board but I still will need to fix the solenoid driver problem. Any ideas? Thanks.
 
I repaired the corrosion effected parts from the battery damage. Now, I get two coils locking on when I power up. I reflowed all the pins on the solenoid driver as there were some cold joints but no change. I'm willing to admit defeat and buy a new main board but I still will need to fix the solenoid driver problem. Any ideas? Thanks.

Either you have a couple of shorted transistors or you bridged some pins when you were doing your soldering.

There are other possibilities but those are by far the most likely (IMO).

Is your MPU booting now? How many flashes if not?
 
One flash only. One of the coils had previously been stuck on as the plastic sleeve was melted. I have replaced that coil.
 
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Here's where I am now: I tested the bottle-cap transitor ( UA78H05SC ) on the solenoid driver board and I have continuity between the collector and emitter. According to my research, that means it is bad, right? If this is correct, where might I find one of these? I could not locate one in my Mouser search. Thanks.

EDIT: I found some parts at Action Pinball. Expensive but available. Order sent.
 
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Here's where I am now: I tested the bottle-cap transitor ( UA78H05SC ) on the solenoid driver board and I have continuity between the collector and emitter. According to my research, that means it is bad, right? If this is correct, where might I find one of these? I could not locate one in my Mouser search. Thanks.

EDIT: I found some parts at Action Pinball. Expensive but available. Order sent.

That's not a transistor, it's actually an integrated circuit - a voltage regulator. If you have 12V or so on the input and +5V on the output then leave it be. If you MUST replace it - use an LM323K.

Ed
 
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