1040 STE Has No Video

[atrain01us]

Hi all,

I have a 1040 STE that is not displaying any video. I have it connected to an atari monitor that I bought at the same time as the computer.

I know that the monitor works because I hooked it up to a Mega 2 computer and a screen is displayed.

Are there anything I can check in the 1040 ste to maybe get it to display video? Is there anyone in the US that can service and repair the issue if I am unable to resolve it on my own?

Thanks in advance,

[exxos]

Have you tried pressing the reset button ? Do you get the power led on the keyboard light ? Is it a stock motherboard ?

[rubber_jonnie]

As well as the power light on the keyboard, do you get any floppy disk activity, such as the drive busy light and drive access sounds?

If you have no power light or disk activity, I'd have a look at the PSU voltages, just be careful as the heatsinks in the PSU can carry high voltages, so avoid then!!!

[atrain01us]

Hi,

The machine is a stock unit with a stock motherboard. The power led does come on when the computer powers up but there is no drive activity and the drive light does not come on when I put a floppy disk in. This unit has only been used in my recording studio for music.

As i said earlier,I know that the monitor is good because I can connect it to a mega 2 computer and get a picture.

So I am stumped at this point but keep the suggestions coming.

Thanks,

[PhilC]

@atrain01us Just for clarity, what do you call no video? white screen? black screen?

It may be worth carefully removing the GLUE and MMU and cleaning them and their sockets with IPA and then reseating them.

[rubber_jonnie]

@atrain01us You mention it is an Atari monitor, but which model? If it is monochrome, then you may simply be getting a fully black screen, which is pretty much the same as a white screen in low or med res.

From what you've said about it coming from a recording studio, then it sounds like it'll be monochrome.

That can often me ROM or GLUE logic.

Or do you get a white border and black screen? That's usually a RAM issue.

If you could take photos and provide more detail around the display that would help.

Also definitely considering what @PhilC said.

[atrain01us]

The monitor is a atari monochrome monitor as it is in my studio. When connected to the 1040ste, there is no picture at all but when connected to the mega 2, I get a clear monochrome screen without making any adjustments to the monitor controls.

Screenshots of the monitor are attached.

Thanks,

06262023121026.jpg

06262023121025.jpg

[rubber_jonnie]

The monitor is a atari monochrome monitor as it is in my studio. When connected to the 1040ste, there is no picture at all but when connected to the mega 2, I get a clear monochrome screen without making any adjustments to the monitor controls.

Screenshots of the monitor are attached.

Thanks,


06262023121026.jpg06262023121025.jpg

If it's mono and you're getting no image, then that is likely a ROM problem, so equivalent of a white screen. I'd be looking to do what @PhilC suggested as a first go.

[atrain01us]

Ok, I'll take a shot at doing the cleaning and re-seating but where are the locations of the items in question located on the motherboard? Also which of the metal covers over the motherboard am I removing? As it currently stands, I'll also look at the connections to the floppy drive as it is not getting any power.

Thanks,

[atrain01us]

Just found out that the 1040ste does not have a mmu and glue chip. They have been combined into something called a gst mcu chip.
It is a 144 pin chip which is soldered onto the 1040ste motherboard with no user serviceable part.

I found this info on: https://info-coach.fr/atari/hardware/STE-HW.php

So at this point, the computer is nothing more than a big paperweight ready to to recycling once I find a replacement 1040ste.

Thanks,