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View Full Version : Think ive bust my 1200 :-(



danhans115
20th May 2009, 11:56
Well not completely. But I got my Flicker Magic delivered yesterday. So I fitted it and the image wasnt right (was all green), so I pushed it down harder and I seem to have snapped one of the SMD resistors next to the LISA chip, its the one nearest the chip - (something to do with the RED signal?) Anyway, on the composite output there was no red at all.

Looking at the markings its a 680ohm. I had a roll of 620ohm normal resistors so I fitted one of those and the red has come back put the picture isnt all that great compared to before. Also the size of the normal resistor means I cant fit the flicker magic.

Can anyone recommend anything else to check round there that might degrade the signal?

And does any recommendations of somewhere (or someone) who could sell me a few of the SMD resistors so I can fix it properly.

Cheers

Dan

arnljot
21st May 2009, 01:54
Zetr0 and Coze might have, da9000 too.

Other than that, I think there's some shop called -- wait -- wait -- google -- google -- www.maplin.co.uk (http://www.maplin.co.uk) ! And then there is www.digikey.co.uk (http://www.digikey.co.uk) too.

Also, replace the rest of the caps. Coze and da9000 knows for sure how to fix this, as Coze did it for one of my machines, and da9000 offered to do it at one amiwest. And Z is the Flux Mastah!

rkauer
21st May 2009, 03:44
Regular-sized resistors have some degree of inductance on them. That's why you have "funny" results.

Swapping the regular-sized for a SMD part will cure the issue.

danhans115
21st May 2009, 11:51
Hi guys, thanks for the reply

@arnljot - Maplins dont stock SMD stuff, which is why I didnt consider them. I live not far from farnells (in leeds) and RS isnt too far either but theres usually a minimum oprder qty/value on stuff like this, hence my post. I shall check out digikey many thanks :thumbsup:

In the meantime Ive got hold of a Magnum 030/40 which is really unstable on my motherboard (a rev 2b - rarely boots - even worse with 32mb SIMM)

Would I be better off getting another motherboard?

Dan

rkauer
23rd May 2009, 03:47
Better check the PSU and electrolytic capacitors. Ripple on the +5V rail cause problems with accelerators.

Also bad contact cause those symptoms Check the accelerator's capacitors and contacts, also do a good clean on the trapdoor connector.