So, as a fan of retro computers, I’m always looking for ways to expand my collection (See the Museum part of this site), and recently started looking at an area of my collection that was missing something: The Atari ST.

I managed to pick up an Atari 1040 STF fairly quickly, but the lack of modulator meant that getting anything other than Hi Res, which works on modern VGA monitors with an appropriate cable, was a pain.

So I resolved to try and get my hands on an STFM model in order to plug that gap.

A non working 520 STFM with good casework came up cheap on eBay, and I though if I could get it running again, then that would suffice, and if not, then it would hopefully yield some useful casework.

Well, I couldn’t bring it back to life, but it did yield a reasonable case, keyboard, PSU and newer TOS roms for the 1040 STF, plus the mainboard may yet be saleable as parts only, as it looks like some of the bits are in reasonable condition, and in fact somebody with greater electronics skills than I may yet be able to ressurect it.

An unexpected bonus was to find installed a Marpet 2MB ram upgrade kit, which will go with the mainboard and PSU as things I can resell to reduce the cost of Project ‘E’.

So, I determined to get a working mainboard to go into my case, and was surprised to find an STE mainboard, with PSU and 1 meg of RAM installed, and all the metal shielding, for just £26.99 plus a very reasonable £7 postage.

A few queries later, I was satisifed it was a runner, and purchased the board before somebody else could beat me to it!!

The idea of Project ‘E’ was thus born, to turn an STFM into an STE, and I awaited the arrival of the new components, which arrived on the 23rd of December, just 4 days after purchase, and quite amazing given the Christmas post!

So, I sat down with my 520 STFM case, and worked out just what would be required in order to slot the STE mainboard in.

As it happens, only 2 minor mods were needed.

1. 2x holes for the audio output.

2. The removal of a plastic lip that supports the cartridge slot.

First off was the 2x new holes for audio out.

As the picture shows, the centres line up vertically with the outside edges of the power switch slot, and horizontally with the modulator hole (At the very bottom of the picture), which is about the same size.

I marked the centres, drilling out both holes, then filing to allow a phono plug to connect properly with no interference.

Next was the lip. The next picture shows the lip beforehand, indicated by the yellow box.

With the case bare, I used a set of side cutters to remove the bulk of the lip, then filed the remainder off flat with the base of the case as below.

With both mods done, the STE board was able to slot into the STFM case, and I was able to reassemble and successfully test the machine.

The difference is visible above, with a metal tongue from the shielding supporting the cartridge slot, rather than the plastic lip on the case.

All in all about an hours work from start to fully assembled working machine.

STE fans will note that I haven’t mentioned a case mod to allow access to the STEs two additional joystick ports, found at the front left of the machine.

Well, that may come later, but since I have no intention of using them, it seemed like a lot of work to mod the case to do so, hence, for now at least, they are going to stay neatly hidden.

Interestingly, the case appears to have slight marks in the moulding that appear to indicate where the hole should be cut, which suggests to me that these, or at least some sort of other port, was intended there, and that it was catered for when the case moulds were made.

Thats my retro fun for the day, happy modding everybody 🙂