Black vertical lines on ST

[czietz]

If you read the AtariForum thread, there I suggested checking the connection from the RAM chips to the Shifter. (... and I was right back then.)

[Steve]

Thanks guys, after checking continuity from the shifter to the ram as suggested by @czietz (pin 2 of every ram chip) I had no continuity on D3 (between ram chip U24 and pin 6 shifter) but after tracking the trace through the board it all seemed fine, then I realised it is the shifter socket which is at fault. I get continuity on pin 6 with shifter removed, continuity dissapears when shifter is inserted. I'll replace the socket next and let you know if it fixes it. Thx for all the help so far guys.

PXL_20210913_100210846.jpg (165.31 KiB) Viewed 2210 times

[Steve]

A picture tells a thousand words, thank you everyone I've learned a great deal during this. Also! I think we should add 'remove/replace any single leaf sockets!' to mandatory fixes

PXL_20210913_103623248.jpg (331.16 KiB) Viewed 2203 times

[PhilC]

[zChris]

Good job! I wonder what can make it have no continuity when the chip is inserted.

/zChris

[Steve]

Good job! I wonder what can make it have no continuity when the chip is inserted.

/zChris

Because they are 'single leaf' (I think it is called) they can easily lose contact. Where as double leaf kind of 'clamps' the leg when pressure is applied.

[exxos]

3M all the way