Monstermug
Active member
Another easy fix on the cards today.
Got a Black Widow from Martin today.
As I already had my Space Duel Jamma Adapter at hand from the Space Duel Repair I did the other day, I connected it to the Black Widow pcb. It uses the same power and tests switch pinouts. As I had nothing else connected I turned it on and wasn't getting a picture.
Checked CPU reset pin and it was high which is good. Checked address lines for data and that was fine. Game seems to be running okay. My attention turned to the VSM side of the circuit. AVG chips are well known to go bad on these Atari PCBS so I changed the AVG and was greeted by a nice surprise.
But it was not over just yet. I doubled checked if the everything else was seated correctly by lightly tapping the board. As I tapped the board, the screen would go blank. Tapping away until I got hotter and hotter to the suspected chip. Again this lead to the AVG chip which I had just replaced. It seems that the socket was bad!
Time to remove the naughty socket.
And replaced with a nice new one.
Plugged in the repo avg chip I had spare and as much flexing and tapping I could, within safe limits of course, would NOT cause the picture to stop. Problem solved!
Then I thought I swap back the original AVG chip that was in board when I first got it.
Bingo. There was nothing wrong with it.
Moral of the story. AVG doesn't always go bad! Almost disposed of a perfectly good AVG chip which is rare as hens teeth these days.
Quite happy as this board is an original factory conversion in lovely untouched condition.
Got a Black Widow from Martin today.
As I already had my Space Duel Jamma Adapter at hand from the Space Duel Repair I did the other day, I connected it to the Black Widow pcb. It uses the same power and tests switch pinouts. As I had nothing else connected I turned it on and wasn't getting a picture.
Checked CPU reset pin and it was high which is good. Checked address lines for data and that was fine. Game seems to be running okay. My attention turned to the VSM side of the circuit. AVG chips are well known to go bad on these Atari PCBS so I changed the AVG and was greeted by a nice surprise.
But it was not over just yet. I doubled checked if the everything else was seated correctly by lightly tapping the board. As I tapped the board, the screen would go blank. Tapping away until I got hotter and hotter to the suspected chip. Again this lead to the AVG chip which I had just replaced. It seems that the socket was bad!
Time to remove the naughty socket.
And replaced with a nice new one.
Plugged in the repo avg chip I had spare and as much flexing and tapping I could, within safe limits of course, would NOT cause the picture to stop. Problem solved!
Then I thought I swap back the original AVG chip that was in board when I first got it.
Bingo. There was nothing wrong with it.
Moral of the story. AVG doesn't always go bad! Almost disposed of a perfectly good AVG chip which is rare as hens teeth these days.
Quite happy as this board is an original factory conversion in lovely untouched condition.
