Issue 3 zeddy no K on screen output

Lardo Boffin · Post by **Lardo Boffin** » Wed Jul 26, 2017 11:44 pm

I built a test ZX8-CCB and attached it to my non functioning zeddy and got no output at all.

I had previously tested my test equipment on a known good zeddy.

So I assume it is not the RF modulator at fault. Does that just leave the ULA / Z80? Both of which are soldered in.

My test setup. In hindsight I should have ordered a bigger box so I could drill two holes to expose the adjusters for fine tuning to individual zeddys.

IMG_6482.JPG: (1.67 MiB) Downloaded 433 times

IMG_6485.JPG: (1.6 MiB) Downloaded 433 times

Something to do another day!

1024MAK · Post by **1024MAK** » Wed Jul 26, 2017 11:56 pm

Is it because the Zeddy is scared of the larger computer it is sat on

...

Lardo Boffin · Post by **Lardo Boffin** » Thu Jul 27, 2017 12:18 am

1024MAK wrote: ↑Wed Jul 26, 2017 11:56 pm Is it because the Zeddy is scared of the larger computer it is sat on ...

I had not considered the intimidation factor before. I will sit it elsewhere!

Lardo Boffin · Post by **Lardo Boffin** » Thu Jul 27, 2017 11:38 pm

So I moved my zeddy from on top of the Apple (6502 vs Z80 - just like at school!) and lo and behold it worked!

Well, that and I removed the ULA, fitted a socket and tried another one...

So it was the butler all along!

I mean the ULA.

Actually not a bad picture for a 184 ULA

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Lardo

1024MAK · Post by **1024MAK** » Fri Jul 28, 2017 1:17 am

Well done that man

Mark

mhudson52 · Post by **mhudson52** » Sat Jul 29, 2017 2:08 am

Nice little enclosure you have! Did you make it?

Lardo Boffin · Post by **Lardo Boffin** » Sat Jul 29, 2017 9:38 am

mhudson52 wrote: ↑Sat Jul 29, 2017 2:08 am Nice little enclosure you have! Did you make it?

I bought the enclosure off eBay, drilled a couple of holes, stuck in a bit of breadboard to isolate the cables from me being clumsy (so just the breadboard gets broken if I yank the cables) and soldered it all together.

In hindsight a bigger box would have been better - very fiddly at that size! Plus I would be able to drill two extra holes to expose the tuning pots.

IMG_6500.PNG: (328.44 KiB) Downloaded 363 times

Lardo

1024MAK · Post by **1024MAK** » Mon Jul 31, 2017 10:50 pm

Hands up! Now don't move! This is a thread heist!

So, about time I posted a photo of my test ZX8-CCB

IMG_5043.JPG: Test ZX8-CCB; (1.12 MiB) Downloaded 338 times

All right! Get back in your waggon and be on your way...!

Mark

mhudson52 · Post by **mhudson52** » Tue Aug 01, 2017 1:26 am

Where did you find those nifty clips?

1024MAK · Post by **1024MAK** » Tue Aug 01, 2017 9:20 am

The ones in my photo were obtained via eBay. Search for 'mini hook test clip". They are some of a pack of ten for £0.99. I reduced the length of the hook slightly (cut a bit off the end) so that it is easier to hook under resistor leads.

I also used an inline phono (RCA/cinch) socket (that I already had) and used some lengths of black heat shrink tubing.

Mark

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Issue 3 zeddy no K on screen output

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Re: Issue 3 zeddy no K on screen output

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Re: Issue 3 zeddy no K on screen output