STe Will Not Boot From Cold.

[Thee]

With a bit of persuasion (flux pen.) I managed to get the other ''Joe Masters'' cap off - 22uf/16v. I can only find a 47uf/35v axial to replace it with. I will solder that in tomorrow and keep fingers crossed that it solves the boot up.

[PhilC]

It does sound like one of the problems I had with a Mega ST, same 556 chip. A bigger cap cured the problem by slowing down the reset time.

[Neffers]

Regarding the ports, get a hold of some decent mod (bodge) wire, and proceed to go from the pins on the ports to the pads they relate to.

By doing this you are simply using the solder pads for the ports for holding them down, while leaving the bodge wires to allow for flexing over time. I can take pics if needed.

Once you have done that, grab some cheap D9's and make your own extender to save the PCB from fracturing. Doubly future proofing that silly design choice lol.

[Thee]

Thank you PhilC and Neffers. I will try that mouse fix if all else fails.

[Thee]

Hi again.

I have only just managed to solder in the cap today - 47uf/35v. I booted from cold and it made it to the desktop without any problem and programmes ran fine.
I switched it off and left for a short while and now it will not boot at all... even the reset makes no difference.

Before I take all the screws out again - does anyone have an idea where I have gone wrong, please?

[exxos]

Bad reset switch ?

[Thee]

I will have a look at that. But, after just replacing the cap's it was all working fine including the reset.
Maybe, it needs a little rest period. When I first changed the TOS chips, some time ago, it was misbehaving for awhile after... I had never seen so many bombs,although it did settle down eventually.

[PhilC]

When you say it won't boot at all, what do you get?

White screen? White and black?

Since you've had the board out, its not impossible you need to reseat the GLUE, MMU or one of the other chips.

You can check the reset switch by using a multimeter btw.

[Neffers]

While you are inside, get the RAM sticks out and clean the edge connectors, possibly try and clean the sockets with IPA or something (nothing Acetone based!). My old STe was a pain with the RAM. I had it when I was a kid and I found that cleaning just the RAM prevented whiteouts or bombing.

[Thee]

Thank you both for your replies and advice.

When I switch on; the power light, Gotek and optical mouse are all active - but, there is no activity upon the monitor although the signal is there. This is the same issue I had before replacing the caps although pressing reset got it to boot.