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I suck at soldering

unity

68020
Pretty sure I do. Just recapped a portable mono. Don't think things went so well. The hard drive spins up now to full speed (thats new). The speaker crackles a little. But the screen display has not changed it patterns and it will not boot. No startup sound, etc. I did disconnect the hard drive in case it was pulling too much power. All cards out.

There are two caps near the programer switches. These I did not replace (missed em!). Like the others, they look sub-par. Would these have any play in the issue or do my soldering skill simple suck? Ugh...

 
In case you used flux, make sure to clean it up since it conducts electricity quite well and can cause all kinds of trouble!

It is also always a good idea to test for 0 Ohm continuity between the cap and the board with a multimeter, that way you can also spot any shorts.

And before recapping, did you wash or clean the board thoroughly? Electrolyte also can cause the same problems as solder flux.

Good luck!

 
Cleaned often with 99% isopropyl alcohol. Minimal flux and cleaned after. I think the problem is that I used the same type capacitors that were install, those evil little trash cans. I had no idea they would be so hard to install with those small feet. Anyway, I will look it over a couple times and see what I can find. If all else, I will order the better caps and replace these.

 
I checked everything over again. I did have one bad pad that I had to repair. Found a trace to it was bad. But still a no go after the bypass surgery. Maybe I will hit up the last two caps by the program switches. Odds are this will get shelved for a while.

 
I third that! I'm a giant with shaky hands. If it's not easy and out in the open it goes to someone better than I.

 
huh? flux isnt conductive...
Rosin based flux is and corrosive.
Thats strange, I had been in the repair industry for who knows how many years, and never once was this an issue. Ever.... Corrosive, sure only if its contaminated. But NOT conductive. If it was, no electronics would ever work after a solder job.

 
huh? flux isnt conductive...
Rosin based flux is and corrosive.
Thats strange, I had been in the repair industry for who knows how many years, and never once was this an issue. Ever.... Corrosive, sure only if its contaminated. But NOT conductive. If it was, no electronics would ever work after a solder job.
Just something I heard. Never really looked into it. If its not, fine. Either way I clean it off.

 
It's hard to say anything about "flux" in general because there are so many different types of it out there.

For example, SparkFun sells (out of stock right now) a Kester 2331-zx flux pen. It's water-soluble so water should clean it off, but it's organic acid, so it's corrosive over a long period of time if you don't clean it. Here's an example of what happened when someone put that flux on a circuit board and let it sit for a month or so. The advantage of this flux is I believe it's more active than other types of flux, but you just have to make sure to clean it off when you're finished. Aside from that first link which also discussed conductivity, I've heard of other people claiming to have experienced random problems that could seemingly be attributed to water soluble flux having slight conductivity, or at least some kind of property that interfered with a circuit. But either way, that should only apply if it's not cleaned off.

On the other hand, there are also plenty of no-clean fluxes out there. Those should be safe to leave on the circuit board after you're done. I personally prefer a Kester 186 pen. As Kester itself says, it's a rosin flux that leaves behind non-corrosive and non-conductive residue. (I clean it off anyway, though--it's ugly and sticky)

Bottom line: all fluxes aren't created equal. Use a good no-clean flux and you should be in good shape :-)

 
I think what you are really asking is this:

----------------------------------------------------------------------------------------

Hello i am unity.

I am new to the forum.

I have this Macintosh Portable that i am working on, Model 5120.

This badly needed some new capacitors.

Would any of you fine seasoned /experienced gentleman be able to help me troubleshoot an issue i'm having?

The issue is:

After i installed some new caps...

No apple bong when i try to boot the machine up, any help would be fantastic!

Thank You.

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Well I would start off by asking you.

What caps did you change?

file.php


all of them are bad and need to be changed.

Next. How are you powering this thing up?

A fully charged 6v SLA battery i presume?

- don't say powerbook 2 or 3 amp charger.

next, you are saying your soldering sucks.

Well if its that bad then you really need to inspect your solder job here:

Screen Shot 2013-12-18 at 4.32.54 AM.png

there are many little traces that run right by the pads there… when in the pad clean up

cap removal process maybe you now have exposed copper traces, and there are solder bridges.

Over all if your soldering sucks... you should remove all of what you did… and re-do it, so it doesn't suck.

the key is Flux + Solder braid, and a gentile pad scrub gets the pads looking new like so:

file.php


 
Damn, thanks for the post! To answer some (if not all)...

I did solder all but two new caps in using the very photo as you posted for reference. The two remaining, which I will do, are at the program/interrupt switches.

I am using a new old stock Portable adapter (output voltage tested) with a charged and tested good Portable battery. That is the portable battery reads 6.3 volts even when left to sit for days after being charged. I am using a new old stock charging base with LED indicator. I do not have any other charges to use.

As for traces, there is some that have a black mark neat the I/O ports and it covers several traces. I will see what I can do to better clean them. I will probably try to pull the I/O port plastic socket for better access.

Like you said, thought, if all else fails I will simply start over. And I will order caps that are easier to place. I have even looked into switching to solder paste and using a heat gun.

 
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