Did I nuke my WWF Wrestlefest (and any suggestions to fix it)?

[Pr3tty F1y]

I see the other WWF Wrestlefest thread below, so if this post needs integrated into that post, please do so. I just didn't want to hijack someone else's thread.


So I had a working WWF Wrestlefest, but the audio had a horribly annoying buzz (Interestingly enough, I picked up another one for a gift/other project and it too has a buzz... so maybe this is common to the hardware?).

Anyway, I figured I'd target the large capacitors first and - due to me not paying attention - while the board originally had polarized capacitors, I ended up with some unpolarized 1000uF 16v caps. From my googling - my understanding was that unpolarized could be used in place of polarized capacitors. However, after swapping out the two 1000uF 16v caps with the deep blue colored unpolarized cap in the image below, I get nothing. My WWF Wrestlefest just black screens, no audio. The yamaha sound chip and 68000 do get warm, but no warmer than usual.

Any thoughts on what I destroyed? I immediately swapped the old caps back in, but no dice. I ended up with some polarized 1000uF 16v caps, but still no dice.

And, to my detriment, while my Wrestlefest was working prior to this - I didn't power it on prior to the soldering (i.e., it was sitting in storage for a few weeks since I last tested it).

So if anyone can point out where my stupidity got the best of me, as it often does, I'd greatlly appreciate your expertise.

 

[ack]

I would start by checking VCC on one of your 74 series logic chips to make sure you are getting 5V.

 

[Pr3tty F1y]

I would start by checking VCC on one of your 74 series logic chips to make sure you are getting 5V.

Thank you for that response!

I finally got my test rig setup in my shop. I checked all of the 74 logic chips on the board and they're all pulling 5.1 volts. I don't have any better voltage control at the moment as I'm running a pico-atx power adapter to an el cheapo supergun "cbox" breakout board, so the there is no way for me to fine tune the voltage down a bit. However, I've ran this rig off of my desk before and there wasn't an issue.

Interestingly, while there was no sound/video, that annoying interference buzz did kick in when the board warmed up about 10 seconds after having it powered on...

I"m guessing I'm going to need a logic probe and/or oscilloscope. However, being a complete novice, I'm likely to get myself into more trouble - so I'm up for any other recommendations. Please be patient with me

 

[XtraSmiley]

Can't help you with the screw up, but my non-recapped board also had crap audio with buzzing. Re-capping it (properly) fixed it.

 

[ack]

Thank you for that response!

I finally got my test rig setup in my shop. I checked all of the 74 logic chips on the board and they're all pulling 5.1 volts. I don't have any better voltage control at the moment as I'm running a pico-atx power adapter to an el cheapo supergun "cbox" breakout board, so the there is no way for me to fine tune the voltage down a bit. However, I've ran this rig off of my desk before and there wasn't an issue.

Interestingly, while there was no sound/video, that annoying interference buzz did kick in when the board warmed up about 10 seconds after having it powered on...

I"m guessing I'm going to need a logic probe and/or oscilloscope. However, being a complete novice, I'm likely to get myself into more trouble - so I'm up for any other recommendations. Please be patient with me

5.1 volts is fine.

The caps you replaced shouldn't have killed the board. One is a power filter cap for 12V and other 2 are specific to sound output. 12V is only used for sound amp, everything else is using the 5 volt rail.

- Have you used your "cbox" on a different board to verify its working ok since testing the re-capped wwfwfest?
- Could you have damaged something else while doing the recap? like bending some pins on the underside of the board causing them to touch?

 

[Pr3tty F1y]

@ack You're the man. The capacitor at C55 got squished by a Taito F3 system + cartridge because I have less than optimal storage conditions. One leg is pulled out, but bending it back got the board to boot. So apparently it wasn't the capacitors after all. So I guess yay, but also I'm am dumb. Thank you for giving me the guidance to get to this point

@XtraSmiley you wouldn't have happened to buy replacement capacitors specifically for recapping your board and still have your receipt, would you? I'd be interested to know what you specifically bought as I'm definitely still trying to educate myself.

 

[XtraSmiley]

Sorry man, it's been years on that board, I just specifically remember it b/c the guy I bought it from on KLOV was a dick and claimed it was fine, one of the few times I've left negative feedback on a sales thread where I actually got the game...

That being said, there is a thread that might have the list for this board. I just buy from Digikey or mouser and buy based on what I read from the old cap. I'm not even sure I do it correctly yet! I get caps that look cool (color!) and are rated higher in temp/usage longer than the stock cap.

https://www.arcade-projects.com/threads/retro-hardware-capacitors-lists.10800/

 

[ForestOfDreams]

Just to add my opinion. Try to get rubycon, nichicon, and for the obscure, panasonic.
I've had good luck recapping many a pcb using these.
If possible, I try to get 105 c long life general purpose caps.
Sometimes you can only get a 85 c
I also get and size larger diameter and width capacitors where they will fit, they last longer.
Uf must match, voltage can be higher, so for example 25v you could substitute 50v.
Or 25v substituted for 16v.
UF MUST MATCH.
On the console side, console5 generally does this same thing and it is easier to just order a kit.
On the arcade side of things, there is generally no kits.
Hope this helps.