zx 48k no graphics

[swalker]

So I finally got my dodgy 48k from the bay of thieves and it was described as above, but was overall dodgy, one of the ribbon s broke on opening and the other was bent! The neutral wire was also loose in the plug, but neither if these fixed the issue. Thanks to @1024MAK I followed his advice in another post and found that the -5V is not there so I have a ZTX 650 on order.
Also the 80s display I mentioned in my hello post is now taking shape.

[1024MAK]

Hopefully just replacing the transistor will get the display back to normal, but don’t be surprised if one or more of the ‘lower’ DRAM chips have failed (or been killed). By the way, the ZTX650 is obsolete, but the higher voltage parts, the ZTX651 or the ZTX653 (both still in production) are suitable replacements.

Mark

[swalker]

Its alive... ish
I get the boot screen but only half the keyboard works.
Bottom 2 rows right hand side out.
I will do a bit of keyboard mashing ( on a workign computer ) to see if the problem is addressed else where. If not ill start a new post.
Thanks for reading
And replying of course Mark.

[swalker]

Fixed, i did mention somewhere the ribbon was in bad nick, quick trim and i have a fully functional keyboard again.
Let the fun begin...

[hellraiseruk]

Another one lives again! Good work

JD

[1024MAK]

@swalker

Well done on bringing it back to life

Mark