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Right, Ok times are a-changin'. I switched the ram around and now with 4 original SIMMs in Bank A I get a single, normal chime. Still no video with the card moved between all 3 bus connectors.... the plot seems to point towards the nubus being bad, but the cheapest I can find is 'untested' on...

Ok, so the plot thickens. I have so far replaced all the surface mounted aluminium caps with tantalums (and I'm pretty good now at safely removing, cleaning and re-soldering these now) and now it powers up, no video and 'death chime' (4 tones, rising in pitch).... I've tried with and without an...

I put an SE/30 ROM in and nothing. I saw the W1 jumper but didn't know what it did, so thanks for that. I can pretty easily re-cap it, as I'm familiar with doing so with SE/Classics - does anyone see a reason not to use tantalums as direct replacements for the surface mounted aluminium caps...

Do you think 'trying anything that'll fit' is likely to do anything other than a no boot?

Hi I've acquired a IIcx in lovely condition. It powers up but no chime and no video. I notice the ROM sim is missing and am guessing this is the issue. I have various other compact macs laying around as well as a bag somewhere full of left over ROM or ROM-esque boards. Can anyone share a photo...

Hmmm, can't seem to find a source of SN74F253 (mine are either branded TI or motorola). I can get SN74F253D - does anyone know what the D means? **edit** looks to simply be stating it's surface mount - just what I need...

Ok it looks like UD8/UE8 are LS166A and UF8/UG8 are LS393, which I can get a few from ebay new. I'll order them and replace all 4 and see what happens. I won't get my hopes up. Is anyone out there able to confirm that I'm correct in thinking UD8/UE8 are the same chip and that UF8/UG8 are the...

I just whipped off UF8, cleaned all the pads, re-attached. The horizontal line is still there, but it does look /different/.... It looks like it's showing graphics but compressed into white line.... Is UA8 and UF7 the same chip? anyone know where I can get new ones still?

I switched the UA8 with a known good IC from another SE/30 with terrible corrosion and...... no change using the 'known good' SE board. I removed it carefully, all the pads look good, gave it a clean and re-soldered using clean new solder and no flux at all. Can't work it out....

I've read all those articles and posts which is why I'm stumped. I've removed as much old solder as possible (I have a rework station as well as using good old copper braid) but still bad. I guess I'll just have to go over the AB all over again. I may well try and remove UA8 altogether and...

SE in SE case = checkerboard SE/30 in SE/30 case = horizontal line. SE into SE/30 case = horizontal line. SE/30 into SE case = horizontal line. Doing more searching I've re-flowed UE8 on the mainboard - no change.

Hi I have an SE and an SE/30 and I'm using both complete units to switch components to try and home in on a few different problems. SE has large black and white rectangle checkerboard. SE/30 has a single, bright horizontal line on the CRT. SE/30- I'm thinking, reflow all the solder on the...

Hi  I have a multitude of faulty analog boards. On many of them the voltage is too high or too low and I think it's related to the trim pots on the board - because some of them do nothing at all. BTW these boards have been entirely recapped by me. I've done about 20 of them so I am familiar...

I also just noticed that chip UJ4 is missing one pin - eaten away completely by battery acid.... I guess i'll find out if that pin is used when I realise the board is a write-off but if anyone has dealt with a missing pin on UJ4 before, i'd appreciate any experiences. There doesn't look to be...

Hi I've got a SE/30 and the clock battery had started to do it's worst. I have got the lion's share off and I believe most of the chips can be cleaned and resoldered. However there are two tiny rectangular blocks, each with 3 pins - perhaps transistors. One is completely gone destroyed, but...

I don't really understand this thread but I have some spare IIfx SIMMS...

Still only 10.4v on the +12v rail. So I'm reaching my wits end now! I've replaced CR20 and 21 with new. I've replaced R39 with new. I've replaced every single cap and then some. I can't understand why the voltage adjustment R59 doesn't do anything. I traced the tracks to R39 thinking it was to...

Hey everyone I'm still trying to work out why one of my analogue board is giving out low voltage. That saga continues. I bought a second working machine in order to restore and then use as a swap machine to troubleshoot with. I tested all the voltages and it boots up with the chime and disk...

I switched U3 with one from a spare board and it's exactly the same... It could be two bad ones but that's less likely than when I started....

I have 4 x Plus boards which test/boot absolutely fine with a different known good working Mac Plus... I also tested the CRT with another Plus, and it's a brand new flyback....! We're down to the analog board. When I say the 128k works, I'm not being entirely full with the facts - I get a...