PhilCs blog / the latest things hes broken(fixed)

[PhilC]

Time to make a homebrew SX64

I certainly have enough parts for one, even an SX128

[rubber_jonnie]

Time to make a homebrew SX64

I certainly have enough parts for one, even an SX128

Now that would be a fun project

[PhilC]

I certainly have enough parts for one, even an SX128

Now that would be a fun project

I’m sure I heard somebody say SX125? Found this self contained colour LCD screen.

It might be the start of an SX125 after all

[PhilC]

As well as doing the housework, etc, today I’ve been clearing up a few loose ends:

The Opus Challenger 3 in 1 is all up and running. It had 1 bad 4256 chip in the second bank and my beeb had a dodgy 1mhz port, quite likely due to nothing ever being inserted in it. A bit of WD contact cleaner and we were all up and running. So now both the RAM disk formats fine and so does the floppy drive.

Next up was to clean up a battery corroded Mac Classic. I’ve had two of these. One had a bad crt, cracked at the neck and the other is far too corroded to be anything but a donor machine. So after cleaning up and swapping some parts from one to the other, switch the power on and………. Nothing! So now I’ve got to make up a crt discharge tool just in case, to swap over the analog boards. I’d recapped the other one so really should have swapped them over before trying to power them up.

Fixed another couple of beeb external drives and have just started on a miracle dual floppy drive for my QL.

I really do need to part with some of this stuff as space is certainly at a premium at the mo and just how many floppy drives does one really need?

[rubber_jonnie]

As well as doing the housework, etc, today I’ve been clearing up a few loose ends:

The Opus Challenger 3 in 1 is all up and running. It had 1 bad 4256 chip in the second bank and my beeb had a dodgy 1mhz port, quite likely due to nothing ever being inserted in it. A bit of WD contact cleaner and we were all up and running. So now both the RAM disk formats fine and so does the floppy drive.

Next up was to clean up a battery corroded Mac Classic. I’ve had two of these. One had a bad crt, cracked at the neck and the other is far too corroded to be anything but a donor machine. So after cleaning up and swapping some parts from one to the other, switch the power on and………. Nothing! So now I’ve got to make up a crt discharge tool just in case, to swap over the analog boards. I’d recapped the other one so really should have swapped them over before trying to power them up.

Fixed another couple of beeb external drives and have just started on a miracle dual floppy drive for my QL.

I really do need to part with some of this stuff as space is certainly at a premium at the mo and just how many floppy drives does one really need?

Those Classics are a pain, from the Maxcell bombs, to the leaky caps on the logic board, and then there is the nest of vipers that is the low voltage part of the analogue board!

Adrian Black just had a Mac repairathon with a Classic and a Classic 2, luckily no battery bombs, but bad caps for sure. I'd say get the little aluminium dustbins replaced as a matter of course.

[PhilC]

So talking about Maxcell bombs, here’s the damage to the classic motherboard after removing all the corrosion.

IMG_3063.jpeg (302.83 KiB) Viewed 1438 times

It’s definitely repairable but some of the small Vias concern me as I suspect there won’t be continuity across the board layers. I guess the only way to find out is to do the repair and see.

Would you repair this board if it’s just a spare and surplus to requirements?

[rubber_jonnie]

So talking about Maxcell bombs, here’s the damage to the classic motherboard after removing all the corrosion.

IMG_3063.jpeg

It’s definitely repairable but some of the small Vias concern me as I suspect there won’t be continuity across the board layers. I guess the only way to find out is to do the repair and see.

Would you repair this board if it’s just a spare and surplus to requirements?

I have 2 boards, one with similar damage and I'm just keeping them for parts TBH. It could be a lot of work, and if they have intermediate layers (I don't know if they are more than 2) then it might be a lot of work to get it going.

[PhilC]

@rubber_jonnie doing some googling I believe they are 4 layer boards. I never did get the first LC-II working, even though everything on the top and bottom layers was repaired, so I suspect that I'd have a similar via issue on this one.

I'll probably keep this for spare parts as well as its not like I need it.

[rubber_jonnie]

@rubber_jonnie doing some googling I believe they are 4 layer boards. I never did get the first LC-II working, even though everything on the top and bottom layers was repaired, so I suspect that I'd have a similar via issue on this one.

I'll probably keep this for spare parts as well as its not like I need it.

Yeah, 4 layers with via damage is definitely a challenge. My non battery damaged spare board died after the caps leaked, and I suspect via damage there too.

[PhilC]

So a bit of news, In between being unwell (ongoing unfortunately but no sympathy needed ). Ive been working on and off with a few things, so the Mac C classic has had a bit of attention over the last week.

The good news is that after changing the Misfit, Opto Coupler, Switch mode cPSU chip, all the common failing caps on the logic board and then some, the first Mac Classic is actually all up and running

So now that I've got this done, I'm actually going to take a punt on that badly corroded board too and see if I can get that to run, just for a bit of fun mind as I'm really not bothered if it does or now.