Asteroids issues (repair log)

timiskander

Well-known member

Donor 3 years: 2011-2012, 2017
Joined
May 3, 2006
Messages
2,667
Reaction score
61
Location
Fayetteville, New York
Wish I had taken pics!
Anyway.. refurbing an asteroids cabaret for a buddy.. Board is a -5. initial power-on leads to +5 led on board, spot killer on tube and not much else. Self test indicates a bad ROM.. 2 legs on F1 fall off when I remove the chip.
o burn a new rom, replace the socket... on to C1... repeat
o Next.. bad 2114 RAM at E2... replaced.. check
o That got us into actual test mode but no +15V... replace 7815 regulator ... check.
o Pull the monitor to see whats up with it... tube is missing 1x2" patch of phosphor right in the middle of the screen... doesn't look like burn, just peeled away... _very_ strange. Order a new tube to replace it...
o Replaced tube... got neck glow and chatter but no pic :( ... HV diode is toast.. replaced... check
o Yea! Finally have a picture to look at... Test pattern is crap :( only fills 2/3 of the width of the screen... bad X output op-amp at C13, now it fills the screen but is stair steps ... jagged..
o Replace the AD561J DAC at D12.. X looks much better, but Y is still stepped.
o Replace the AD561J DAC at B12.. Yea! a test pattern!!
o Some of the buttons not working so well... burnish with an old biz card (NOT sand paper!!!) and adjust switch gap... check
o Finally.... I can play asteroids! ... leave it to burn in a bit.. come back to a dead game :(
o Push on the ROMs... game appears again... replaced _all_ the ROM sockets :) [ should have just done that when I saw 1 was bad! ]
Game is all happy now... this poor little guy had a hard life I guess...

cheers
/Tim
 
Nice work, Tim! Wow, new a CRT & 2 DACs... sounds like an expensive Asteroids repair.
 
Back
Top Bottom