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Re: H5 A3 FIXES
Posted: 04 Nov 2020 14:04
by Steve
@DoG
Just confirming (I don't want to get the wrong one)
Would it be this:
https://www.mouser.co.uk/ProductDetail/ ... Iyxg%3D%3D
Re: H5 A3 FIXES
Posted: 05 Nov 2020 17:20
by Steve
Okay I'm just gonna order this.
Re: H5 A3 FIXES
Posted: 05 Nov 2020 17:35
by DoG
Sorry. I read this at work but didn't had time to answer then. Then I forgot about this thread... until now.
But, yes, that should be the correct part as @Icky said.
Re: H5 A3 FIXES
Posted: 05 Nov 2020 19:29
by Steve
Thanks @DoG :)
Re: H5 A3 FIXES
Posted: 30 Nov 2020 06:15
by kodak80
exxos wrote: 29 Oct 2020 15:34
SIDE0 FLOPPY SHORT FIX
There is a short from pin 21 of the YM2149 to GND at the right hand side hole of the DB19 connector..
https://www.exxosforum.co.uk/forum/downl ... p?id=15043
It is not actually shorting on the top of the hole as it appears to in the image..It is one of the inner layers, but the inner of the via also excludes outwards from the hole which is causing the short.
The only fix I can come up with is to gently file away the hole as indicated below until the short is removed... I'll suggest using a meter to check pin 2 of the external floppy port, to the outer ground while you file to make sure you do not cut too far otherwise you will damage the track next to it which is what I did :(
I would suggest filing the sides of the hole as much as you are filing the top of the hole... Once you break continuity checked both sides of the track on pin 2 of the external floppy connector, to ground, then the YM chip side on pin 21 to ground..
Once both sides of the track are broken from ground you need to bodge wire from pin 21 of the YM chip to pin 32 of the floppy internal connector...
Done.
If you file to far you will break the track above which is what I did, and that then needed a bodge wire...
I have started with my first A3 board and this fix. Are there any other tracks above that could also be cut when filing the hole? Is it only 1 additional internal track as I may have filled too far and have the same issue
@exxos created. Just wondering if I may have cut any other tracks I need to check may have been cut?
Re: H5 A3 FIXES
Posted: 30 Nov 2020 07:26
by exxos
Re: H5 A3 FIXES
Posted: 30 Nov 2020 09:13
by kodak80
That was what I thought. Besides the one to be cut and the one you cut, the image does not show where the other 2 tracks run from and to so I can test to see if these are now cut or not?
Re: H5 A3 FIXES
Posted: 30 Nov 2020 11:22
by exxos
kodak80 wrote: 30 Nov 2020 09:13
That was what I thought. Besides the one to be cut and the one you cut, the image does not show where the other 2 tracks run from and to so I can test to see if these are now cut or not?
I've updated the post with images of the other 3 tracks.