Build Your Own Arcade Controls Forum

Arcade Collecting => Miscellaneous Arcade Talk => Topic started by: MYX on September 24, 2006, 10:05:59 pm

Title: Cap question
Post by: MYX on September 24, 2006, 10:05:59 pm
Hey all,
I am replacing Caps in my Black Knight.
I am seeing a variety of caps at a variety of prices.
Also is axial actually different from radial or is it the same with just different configurations?

What makes a little 100MCF 150V cap different from a big 100MCF 150V cap?
Title: Re: Cap question
Post by: Boz on September 24, 2006, 11:23:57 pm
Isn't this in the wrong forum? There's some real geniuses over in the Monitor / Video forum if you wanna have it moved there. Just a thought.  :)
Title: Re: Cap question
Post by: Kevin Mullins on September 25, 2006, 03:03:20 am
I wouldn't say it's the "wrong" forum.... it's still just a general question of sorts, but caps are very common in working on monitors.  ;D

Axial caps are the ones laying down on there side with one lead coming out of each end.

Radial caps are the one standing straight up with two leads out the bottom. (most commonly found)

The majority of caps are polarized (a + lead and a - lead) but then there are Bi-Polarized caps that are generally marked with a "BP" which are just that... not polarized. (no + or -)

As for the ratings and size issue:
The size of the cap doesn't matter, it's just a difference in manufacturer design, etc.
What does matter is the uf (MCF) and the voltage ratings.
When replacing a cap the uf rating (10uf, 100uf, 22uf, 3500uf, etc) should always be exactly as the one you are replacing.
The voltage rating can be the same or higher than the one you are replacing, but never lower.

Mouser is a good source for lots of little parts like this.
http://www.mouser.com/ (http://www.mouser.com/)

It's late, I'm tired, hope this helps out a bit.
Title: Re: Cap question
Post by: MYX on September 25, 2006, 07:57:55 am
Isn't this in the wrong forum? There's some real geniuses over in the Monitor / Video forum if you wanna have it moved there. Just a thought.  :)
It is not for a monitor. I am replacing caps in a pin and in my millipede.

Kevin I was aware of the polarization thing. I learned the hard way in my studio maintanance class. In our first week we had to build a circuit (a fairly simple one) and I goofed it because if this. Each persons circuit was supposed to be able to connect to the next persons. If the whole class could not make continuity it got broken down to see who did it. Fortunatly, I saw the issue when another classmate got stuck with the blame. Stuck with me.  ;D

Asside from the way their built, If I can not find an appropriate axial in the right size, I can replace it with a radial. Correct?
Title: Re: Cap question
Post by: SirPeale on September 25, 2006, 08:08:03 am
Isn't this in the wrong forum? There's some real geniuses over in the Monitor / Video forum if you wanna have it moved there. Just a thought.  :)

It does belong in Arcade Misc, he's talking about his Black Knight pinball game.
Title: Re: Cap question
Post by: SirPeale on September 25, 2006, 08:09:56 am
Asside from the way their built, If I can not find an appropriate axial in the right size, I can replace it with a radial. Correct?

Technically, yes.  But you may find it quite difficult to fit it into the space available.

What is the cap you're having trouble finding?
Title: Re: Cap question
Post by: ChadTower on September 25, 2006, 09:32:13 am

He could probably find rebuild kits for any board in his Black Knight.  They're standard highly known System7 boards.
Title: Re: Cap question
Post by: MYX on September 25, 2006, 09:50:33 pm

He could probably find rebuild kits for any board in his Black Knight.  They're standard highly known System7 boards.
Yup, I already got a BK Sound cap kit from Bob Roberts. I was having issues where the sound would not come on for about 15 minutes. I figured it was taking something that long to heat up enough or taking that long to build enough of a charge. I also reflowed all major solder points. Seems like it not only works better (sound upon power up) it sounds nicer. (Smoother somehow)(Could also just be in the head though).
I figured I would hit mouser to replace the others. there is a 12,000MCF 16v (the one in question). (Main Power)
1 30,000 25V   :P (Filter)
2 100MCF 150v
1 100MCF 100v
1 100MCF 10v
Title: Re: Cap question
Post by: Boz on September 26, 2006, 01:33:57 am
It is not for a monitor. I am replacing caps in a pin and in my millipede.

Man. I *hate* being taken to school.  :-[

Carry on... nothing to see here.

 ;D
Title: Re: Cap question
Post by: MYX on September 26, 2006, 07:58:59 am
It is not for a monitor. I am replacing caps in a pin and in my millipede.

Man. I *hate* being taken to school.  :-[

Carry on... nothing to see here.

 ;D
I know, it still got moved.  ;D
It's just Peale flexin his 'athoritie' muscle.  ;) (Still hearing Cartman sayin'...YOU MUST RESPECT MY ATHORITIE)
Title: Re: Cap question
Post by: MYX on September 26, 2006, 08:02:53 am
BTW Chad,
Since you are like the resident Pinmaster...
I noticed that the the caps near the edge of the PCB were really hard ro remove. It was like they were sort of embeded into the trace. It took holding the iron forever (and a bit of elboe grease) to finally let it break free. Is it a harder solder on the edge or should I have used a higher heat? I was worried about hurting something with too high of heat.
Title: Re: Cap question
Post by: ChadTower on September 26, 2006, 08:57:27 am

That's not a pin issue, that's just standard soldering.

Old solder can be a pain at times.  It could have been partially oxidized, making the melting point higher, or maybe there was something sinking the heat off of it.  In the future, use some small wire cutters and cut the components off.  Then you can just desolder the legs and it's much easier.  When you get good at it you can often make the leg just fall out of the board after one shot with a solder sucker.

It probably doesn't have anything to do with being near the edge of the board.  Another trick you can try is adding a little new solder to the pad before  trying to remove anything.  It sounds counterintuitive but you'll see why when you've done it a few times.
Title: Re: Cap question
Post by: MYX on September 26, 2006, 09:09:18 am
In the future, use some small wire cutters and cut the components off.  Then you can just desolder the legs and it's much easier.  When you get good at it you can often make the leg just fall out of the board after one shot with a solder sucker.
Yeah, I was using a sucker (not the bulb type, it's the spring loaded tube type). But good idea about cutting it off first.

It probably doesn't have anything to do with being near the edge of the board.  Another trick you can try is adding a little new solder to the pad before  trying to remove anything.  It sounds counterintuitive but you'll see why when you've done it a few times.
I was doing this. It was wierd, the stuff would just not liquify. I would wait a while with a ball of liquid solder right on the leg. Then I would get the sucker and hit the hot spot and the only thing that had left was the fresh solder. The old stuff was solid (really hot, but solid) Once the cap came out, the board still had a cone like protrusion where the cap was. It was like it was a different metal or something. I eventually got some flush cutters and snipped it flat with the board. When the new cap was in I checked continuity with the DMM to make sure I had not broken any traces with the snip. The caps that were not on the edge came out with no problems. Heat, melt, suck...clean.
Title: Re: Cap question
Post by: ChadTower on September 26, 2006, 09:16:56 am

Contaminated.  Did you clean those joints off before trying to desolder?
Title: Re: Cap question
Post by: MYX on September 26, 2006, 07:14:59 pm
Contaminated.  Did you clean those joints off before trying to desolder?

Said in my best Tommy Chong
No Man... I smoked em.  8)

What would I clean it with? When I was doing the millipede A/R board I used alchohol to clean it because it was cruddy. But I did not see any gunk on there. It 'looked' clean. But I do understand things can build up too.  :P 
Title: Re: Cap question
Post by: ChadTower on September 26, 2006, 09:37:20 pm

Alcohol.  If you heat up the solder, and there is a film on it, the film just mixes with the solder and contaminates it.
Title: Re: Cap question
Post by: MYX on September 28, 2006, 09:58:43 pm
I am having trouble finding a 30,000mcf 25v cap. I would assume that I can go paralell with a couple or several smaller caps. Right?

Edit:
How about 3 of these (http://www.mouser.com/search/Refine.aspx?Ne=1447464+254016+688315+688767+684043&N=1323038+4294826922+4294966457+684043+0&GetRecs=1&Ns=P_SField&Msb=0&RefType=Home)
Title: Re: Cap question
Post by: Lutus on September 29, 2006, 04:12:36 pm
33000uf is the more standard value.

Then again, 15000uF is also standard.

Two of those in parellel would be easier to mount than 3 10000uf Caps.

Try Mouser and Digi-Key
Title: Re: Cap question
Post by: CheffoJeffo on October 03, 2006, 03:56:08 pm
Asside from the way their built, If I can not find an appropriate axial in the right size, I can replace it with a radial. Correct?
Technically, yes.  But you may find it quite difficult to fit it into the space available.

Found this article as I was browsing Bob's site looking for G07 rebuild kits ...

http://www.therealbobroberts.net/axial.html

Cheers.