A poorly Zeddy

General Chit Chat about Sinclair Computers and their Clones
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Andy Rea
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A poorly Zeddy

Post by Andy Rea »

Question what do you with with a zeddy that looks like this ?
Image

some may say scrap it.... but me...
Image

i see it as more of a re birth.... for a little project i have in mind :lol:

Andy
what's that Smell.... smells like fresh flux and solder fumes...
sirmorris
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Re: A poorly Zeddy

Post by sirmorris »

Keep those pictures coming!
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Andy Rea
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Re: A poorly Zeddy

Post by Andy Rea »

a little more progress on the re-build
ula, cpu and rom socket in place... and a few other bits that are too big...
Image

I'm tying to squeeze most of the passives on the back side using SMD ( if i have the correct values )
Image

regards Andy
what's that Smell.... smells like fresh flux and solder fumes...
sirmorris
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Re: A poorly Zeddy

Post by sirmorris »

DO IT! Only the best people have smd passives on the back side ;) ;)

With the right size you can place them between the pins. I think these are 0805s.
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But why would you want to remove obstructions from the top side? Careful. You know where this kind of tomfoolery ends up...

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WHAT ARE YOU DOING MAN! STOP IT! THINK OF THE CHILDREN!
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Andy Rea
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Re: A poorly Zeddy

Post by Andy Rea »

more work on the board today, most of the top side done.
Image
The Bottom side, mix of through hole and smd.
Image
bit of a hodge podge of diodes :D
Image
bodge on a nearly empty RF can, you might notice no ear / mic circuit yet !
or memory :mrgreen:
Image
and after a little debugging and poking around with a scope i found 2 shorts,
one that i should have definitely spotted had i have looked properly, the other
a tiny solder splash across 2 adjacent tracks.
Image
i just need to add some ram... now then how do you fit an SMD ram chip into
an 81... oh yeah i remember now....
Image

Regards Andy
what's that Smell.... smells like fresh flux and solder fumes...
sirmorris
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Re: A poorly Zeddy

Post by sirmorris »

YES! That's what I'm talkin' about ;)
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1024MAK
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Re: A poorly Zeddy

Post by 1024MAK »

sirmorris wrote: Sun Sep 10, 2017 11:48 pm YES! That's what I'm talkin' about ;)
Calm down lad, you're blow the top off your chip! :lol:

Mark
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Paul
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Re: A poorly Zeddy

Post by Paul »

You could solder the SMD RAM directly to the underside of the zeddy
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Re: A poorly Zeddy

Post by nollkolltroll »

This is starting to look really interesting. Give us MORE!
/Adam
Zxkim81
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Re: A poorly Zeddy

Post by Zxkim81 »

I take my hat off to you Andy and your vision for that poorly zeddy brought back to life is memorising.
Is that a re-designed ula on that atmega chip I see.😋
Well done Andy well done🤔
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