Removing a ULA

Discussions about Sinclair ZX80 and ZX81 Hardware
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mrtinb
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Removing a ULA

Post by mrtinb »

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This is not the way to remove a defective ULA. There's no room. Aargh... I'll try again tomorrow.
Martin
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ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
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Andy Rea
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Re: Removing a ULA

Post by Andy Rea »

Oh my... where you trying the hammer method :lol:

Well now that's happened i would use a small.pair of side cutters to cut each pin remove the bulk of the chip and the one at a time remove each pin with tweezers and soldering iron, clean the up the pads and your good to go.
what's that Smell.... smells like fresh flux and solder fumes...
MaFli
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Re: Removing a ULA

Post by MaFli »

Wow... That one must have been running quite hot :D
Or did you Widlarize it?

(https://en.wikipedia.org/wiki/Bob_Widlar)
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mrtinb
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Re: Removing a ULA

Post by mrtinb »

I'm trying to remove it but I don't have a cutter that's small enough. And I gave up desoldering.

To put it simple: I don't have the tools to remove an IC.
Martin
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ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
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PokeMon
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Re: Removing a ULA

Post by PokeMon »

Well - this is not a high quality tool like side cutters from Knipex (I prefer) but sufficient for this job.

http://www.ebay.de/itm/Red-Plastic-Coat ... SwR29ZLovl
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mrtinb
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Re: Removing a ULA

Post by mrtinb »

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Once again Dremel is your friend.
Martin
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ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
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mrtinb
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Re: Removing a ULA

Post by mrtinb »

Finally! The tinsucker was great help. I hope I didn't cut some traces during the battle.

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Martin
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PokeMon
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Re: Removing a ULA

Post by PokeMon »

Well - I would use a socket now rather than soldering the next ULA again directly. 8-)
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mrtinb
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Re: Removing a ULA

Post by mrtinb »

That's the plan.

Is there an issue 3 pcb layout somewhere?

I think I have bruised a connection. It would be easier to find that with a pcb layout than using a schematic.
Martin
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ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
brozier
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Re: Removing a ULA

Post by brozier »

Is the bruised connection visible with the ULA in place?

I have an early Rev 3 board with the older ULA in it. Happy to take pics if you need them...

Cheers
Bryan
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