Will someone fix my A1200 accelerator board?

[Dimlow]

Opps, just checked RS the simm sockets are only 3.39 ish, the 90 deg ones i was looking at a few weeks ago are the expensive ones. as you have a tower the cheaper one should do the trick

Oh, and i have no heat sink on my 80Mhz 060, just a small fan to circulate air over the chip, the lastest 060 cpus run quite cool

[bigfoot]

Thanks Dimlow for your kind offer, I'll let you know what will happen next week as am on holiday at the moment

Regarding those pr0n photos, I'll see what I can do when I get back to base next week.

[bigfoot]

Well Dimlow, I have considered for a long time and have decided to sent it away to PG, simply because he'll be fitting that battery which I require.

In the mean time I've got another board and am trying to get it to work

Anyway, lets look at some 'before' photos

[Dimlow]

Nice photo's. Im sure PG will be able to sort it all out for you. I can see from the pics that there is considerable corrosion around the clock chips and the jumpers. before you send it off id suggest you give the jumpers a good clean and see if that sorts out the problem. The 1240's needs a good clock signal to function well.

What is this other board, another 1240? maybe that one from ebay last week. The one that went for about £30, i was going to get that one but i missed the auction!

In the mean time i purchased a couple of busted DS lites to keep me busy.

[bigfoot]

This time it is just a vanilla Amitek Hawk 0-8 meg ram expansion. Of course, I am having problem running the darn thing I can't get the board to recognise any sticks of ram that I've put in so far.

[papa_november]

If no boards are working in your 1200, then maybe it's your 1200 that's malfunctioning? Do you have access to another machine for testing?

[Smiley]

Strange, I always thought Apollo 040s came with coin battery clocks with a white cover. Well at least mine did.

I wonder if there are any updates on the card from bigfoot?

[Dimlow]

So bigfoot, did ya get it fixed ?

[bigfoot]

I've given up. Currently using a 2 meg sram card that plugs into the PCMCIA.

[Fingerlickin_B]

I like dead accelerators...you selling it?

PZ.

[Dimlow]

@bigfoot

Hi ya, i have taken another look at you 1240 pictures and I'm confident that there is corrosion around the 74f74 chip, two of the boards i have fixed have had this problem, replacing the chip and maybe fixing some broken links would probably fix the board. This come from battery leaks. If you have a multimeter some simple checks can be made to see if the corrosion is the problem.
please check for continuity between the following pins of the 74f74 chip

2 and 6
4 and 10
8 and 12
13 and 14
1 and 14
3 and the 060 pin on the clock jumpers
11 and the 040 pin on the clock jumpers

[DoogUK]

same scenario on my card and i have no continuity between 3 of those points......dead f74 chip?

[Dimlow]

Could well be, but i suspect that the board has corroded, i got some of those chips on the way here, you not posted it yet then doog ?

Here is what it looks like under the chip, when the battery has leaked. I think this will soon become a common problem with all these boards

[DoogUK]

Not had chance to yet...i will do hopefuly tuesday.

Glad there's a new apollo doctor in town

[alexh]

That doesn't look too bad. Just a bit of discoloration in the PCB lacquer caused by the acid. Are there really continuity problems in that photo?

[TheCorfiot]

@Dimlow

Has the acid caused non continuity with the through hole's ??

If not I agree with alex it don't look too bad

TC

[Dimlow]

Simply answer, Yes two! This photo is after the board has been cleaned the discolouration is under the solder mask!
The two tracks that run under the chip have the problems, the via's are ok

Also on this board the chip was also dead plus the processor! I guess it had a bad time maybe shorted.

[bigfoot]

Wow, Doctor Dimlow. I'll definitely look into it. Thanks again.