Stuff and Things.

[exxos]

@PhilC That was his dishwasher last week...

[PhilC]

@PhilC That was his dishwasher last week...

ok, so he'll be used to it by now then

[rubber_jonnie]

@PhilC That was his dishwasher last week...

ok, so he'll be used to it by now then

Actually, the dishwasher wasn't that far off that pic

As for the TF, we'll see!

[rubber_jonnie]

Cool, final packages of capacitors are here so I can crack on and finish the Mac Classic analog board re-cap tonight

[rubber_jonnie]

Hmmm, grumble grumble, Mac still dead.

At least the analog board is giving it the right power now, so I'll take that.

[atari030]

I feel your pain. I think you got it and.....

[Tomswork]

I love old mac's they are just as easy to fix as trs-80 machines

@rubber_jonnie

Time to reseat the roms and ipa the board. If works then those horrible can capacitors



Tom

[rubber_jonnie]

I love old mac's they are just as easy to fix as trs-80 machines

@rubber_jonnie

Time to reseat the roms and ipa the board. If works then those horrible can capacitors



Tom

I already replaced the logic board caps, but no change. I did clean the board with IPA, but I've also taken the plunge and washed and gently scrubbed it as is suggested pretty much everywhere on the web! It had a final good rinse with clean fresh water and a blow out of all the sockets to get rid of any excess water in the pin holes, and is now in our drying cupboard. It worked about 6 months ago, so I think it should be fixable.

I would add there is no visible corrosion or cap leakage anywhere other than the analog board, and the battery, now removed, had not leaked either.

My main concern now is the ROM. I removed it to clean the pins and spray contact cleaner in the socket (This was before I decided to wash it) and the ROM is a single 512K item, 40 pin. The socket is 42 pin which I didn't notice when I removed it, so on plugging it back in and powering on, the ROM got quite warm to the touch. I have to say that the markings on the board are a bit misleading IMHO.

I have corrected that now having checked against an image of the same board, but have a worry that I fried the ROM.

I do have a ROM image so could make a replacement, but I don't know what EPROM/PROM would be a suitable replacement. Any advice here would go down well.

@cmorley Would your ROM emulator work in this scenario? The original ROM is 512KB.

I note that the 27C800 is 42 Pin, so wondering what my options are if I need to burn my own.

[cmorley]

@cmorley Would your ROM emulator work in this scenario? The original ROM is 512KB.

I note that the 27C800 is 42 Pin, so wondering what my options are if I need to burn my own.

If it needs a 27C800 then yes the emulator should work. Pin 1 is A18 and pin 42 is NC on an M27C800 (1MB). Best thing to do is use a 41 pin strip of pins with one hanging off at the pin 1 corner - then use a short piece of wire to connect A18 pad to the spare pin (now pin 1). Or a just use some solid core instrument wire and poke it into the A18 socket.

Then configure the module as 27C800 from the options menu wizard.

Of course if you only need 512KB configure as 27C400 then plug it in leaving pins 1 & 42 free as you would in an Amiga...

(I am half wondering about putting castellated half holes above pins 1 & 40 on the emu so you can solder 42 pins of pin strip on without wires.)

[rubber_jonnie]

@cmorley Would your ROM emulator work in this scenario? The original ROM is 512KB.

I note that the 27C800 is 42 Pin, so wondering what my options are if I need to burn my own.

If it needs a 27C800 then yes the emulator should work. Pin 1 is A18 and pin 42 is NC on an M27C800 (1MB). Best thing to do is use a 41 pin strip of pins with one hanging off at the pin 1 corner - then use a short piece of wire to connect A18 pad to the spare pin (now pin 1). Or a just use some solid core instrument wire and poke it into the A18 socket.

Then configure the module as 27C800 from the options menu wizard.

Of course if you only need 512KB configure as 27C400 then plug it in leaving pins 1 & 42 free as you would in an Amiga...

(I am half wondering about putting castellated half holes above pins 1 & 40 on the emu so you can solder 42 pins of pin strip on without wires.)

As it happens, I only need 512KB, so I can configure as a 27C400 then, which would be easier. Still getting my head around ROM sizes!!

That damn mobo socket is so easy to get wrong

Thanks!!