Jump to content
Due to a large amount of spamers, accounts will now have to be approved by the Admins so please be patient. ×
  • 0
IGNORED

Space invaders 3 layer board.


BIG Trev

Question

I need help on this one. Is there anyone willing to do a paid repair job on my Spacies cocktail board set? C2 on the 12v line going to pin 28 on the 8080 just let the magic smoke free. I could replace the 8080, its socket and the 22uf 16v tantalum cap that blew but I'm still learning and don't want to stuff this one up any worse.

Cheers Trev

 

Sent from my SM-G900I using Tapatalk

Link to comment
Share on other sites

14 answers to this question

Recommended Posts

  • 0
  • Administrators

I should have looked at the 8080 pinout I didn't realise it used oddball voltages.

Those Tantalum caps are prone to shorting, they frequently go with a bang on old WPC sound boards and one blew up on a Moon Patrol sound board just recently.

Just replace the cap mate. are you sure the CPU was smoking and not just the cap looking like it?

Link to comment
Share on other sites

  • 0
I should have looked at the 8080 pinout I didn't realise it used oddball voltages.

Those Tantalum caps are prone to shorting, they frequently go with a bang on old WPC sound boards and one blew up on a Moon Patrol sound board just recently.

Just replace the cap mate. are you sure the CPU was smoking and not just the cap looking like it?

Hi Trav,

It was the cap that blew but the socket copped a bit of the bang too and when I removed the 8080 a leg fell off. Not my day.[emoji12]

 

 

Sent from my SM-G900I using Tapatalk

Link to comment
Share on other sites

  • 0

As Trav has mentioned, those Tantalum capacitors are prone to failing and going out with a bang, but chances are no other damage was done. I can look at your board, but I have so many board repairs backed up I really don't want to take on more until I clear what I have here. I'm happy to send you a tested 8080A pull if you like Trev? I'd also replace the socket for the CPU myself, as it sounds like it could be quite old and likely single wipe contacts.

 

Regards,

 

Johns-Arcade.

Link to comment
Share on other sites

  • 0

I'll remove the socket and what's left of the cap and go from there. I should have a new socket here somewhere so I can fit that until the parts I've ordered arrive.

Thanks for the offer of a cpu John but I'll wait until the one I've ordered arrives. I've still got some Wonderboy boards to make test harnesses for and I need to build the por circuit for the Spacies board.

Just out of interest how do I add credits on the Spacies board on the bench as I don't have a credit board hooked up?

Cheers Trev

 

Sent from my SM-G900I using Tapatalk

Edited by BIG Trev
Link to comment
Share on other sites

  • 0
I'll remove the socket and what's left if the cap and go from there. I should have a new socket here somewhere so I can fit that until the parts I've ordered arrive.

Thanks for the offer of a cpu John but I'll wait until the one I've ordered arrives. I've still got some Wonderboy boards to make test harnesses for and I need to build the por circuit for the Spacies board.

Just out of interest how do I add credits on the Spacies board on the bench as I don't have a credit board hooked up?

Cheers Trev

 

Sent from my SM-G900I using Tapatalk

 

No need for the credit board, just coin to ground.

 

Regards,

 

Johns-Arcade.

Link to comment
Share on other sites

  • 0

I've put a 8080 from another board in this and replaced the tantalum cap with a new one.

It now shows changing garbage on the screen and you can hear a dull ufo in the background when the reset is held low and there are text and partial sprites showing. I can't check the roms as my progrmmer won't read them. I have data, address and clock signals on the cpu, checked with the logic probe. I'll have to check with the oscilloscope to know for sure.[emoji6]

I'm guessing I'll need a better programmer soon and something to check the ram?

Cheers Trev

 

Sent from my SM-G900I using Tapatalk

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...