Cap Kit with Different Capacitance than On Chassis?

[dgame]

Hi,

I just finished installing a Bob Roberts cap kit on my 27” Wells D9200 (Model 27D9204 on the frame.)

I understand that the capacitors voltage ratings can be different (usually higher) but what about capacitance?

Specifically:
C806 on the cap kit list is 33uF 25v but the board had a 1uF 50v there.
C810 on the cap kit list is 100uF 25v but the board had a 220uF 50v there.
Which should it be?
Could this be some kind of fix/update?

The values in the cap kit list are consistent between the Bob Roberts kit and the 27" D9202 cap list posted here:
 http://forums.arcade-museum.com/showpost.php?p=1131876&postcount=4

The values on the board are consistent with these documents from Wells-Gardner:
http://www.wellsgardner.com/bom/PD279200.pdf
and
http://www.wellsgardner.com/pdf/Schematics/D9204_D9205_Schematics.pdf

I already put in the ones from the cap kit, should I change them back to the original board values?

EDIT:
There are also four instances where the voltage in the cap kit is less than the board:
C422 is 50v vs 63v on board
C425 is 25v vs 35v on board
C823 is 25v vs 35v on board
C847 is 25v vs 35v on board
Are these okay? I haven't put power to it.

Thanks!

[dgame]

Okay, I went ahead and bought the original board value caps locally and switched them in. Powered it up and everything looks fine. The only problem is the monitor emits a slight buzz when the video signal is applied. What could be causing this buzz?

Thanks

EDIT:
The surge protector/power strip was causing the buzz switched it and the buzz went away.

Now for the good news. The monitor is beautiful!

[BC_Jeffro]

flyback
my DK cab is loud and i know the fly-back is bad on it

[dgame]

Thanks for the reply.

I had already cured the buzzing, but I cranked the flyback 'screen' pot down a bit as I had it turned up before the cap kit.
The screen is much brighter at the same pre-cap OSD values.

Doing the cap kit was very much worth it.

[MonMotha]

Though this has been resolved, the issue may be that somebody had already capped it in the past.  People frequently replace with higher voltage ratings, but your kit may not have had the increased ratings (or may not have had them increased as much) from the originals.  Chances are, they were probably OK.  However, the higher rated ones will probably last a bit longer.

[dgame]

I think the revisions made the difference with cap kit being for D9202 vs. my D9204. So the values were probably officially raised on those different caps. You are probably right that it would have worked with either of the caps. This was my first cap kit so I didn’t risk it as destroying the monitor would effectively end the project.

[qrz]

an example of an engineered failure is 'lytic voltage ratings .
i.e. using a 6.3v cap on a 5v line , 16v on 15v etc.......... leaves little room for surges 
THEN they put 'em as close to a heat source as possible . 

helps fuel the throw away mentality.....

[MonMotha]

The general best practice I've always heard (and try to implement) is that the cap on a DC power rail should be rated at either double the nominal supply voltage or ~25V above the supply, whichever is less.  Beyond that, going to a higher temp rating/longer spec'd lifetime seems to do more good than increasing the voltage rating higher.

Of course, not putting them right next to the 25W ballast resistor also helps...