Thursday, 16 July 2015

Return of the Schneider Euro PC



I've bought another Schneider Euro PC. This one has the power supply included+Schneider Joystick and mouse. The computer has a game card installed, which is pretty useless though: it simply has two joystick ports.

The outer appearance was very promising: virtually no yellowing on the computer or the keyboard.

Compare this to my other Euro PC, which I discussed here. In this picture, it's the one below.

The case yellowing is not as visible from the photo, but it's there.

However, a look at the inside revealed a sad truth: the battery has died and corroded some parts of the PCB.

Does not look too bad? Look at the surface mounted chip peeping at the bottom right.
Nurture, not nature. My other Euro PC computer had yellowed heavily, but the board had remained intact. The reverse has happened here, the board has suffered but not the cover.

I of course removed the battery. Also, did some reading on the net, and it appears that the PCB corrosion is a many-splendored thing. It would be best to take a board with this damage to a professional...

Well, I simply lathered the PCB with WD40 (Good enough for your dad, good enough for you) and started cleaning it with Q-tips and scratching between pins with a paper knife.

I'd like to say this heroic activity had some positive outcome. But... no, on power-up the machine just lets out one horrendous wailing beep, and that's it.


Connecting to Commodore 1084S


It's not all sadness and gloom, though. At least I got a proper power supply for my older Schneider Euro PC, which has been proven to work. Also, as I now have a monitor with TTL RGB support I could easily connect my Euro PC to it. I could have arranged both by other means, but it would have been more trouble. 

Now what to do? The Euro PC has the only working PC floppy drive in the house.
I still needed the cable, though. I went to a flea market and bought a fat old SCART cable. My soldering has gotten (more) rusty, so building the cable took a surprisingly long time. Hint: It's worth removing all the unneeded wires near the end so you can fit it into the DIN housing...  It's also a great idea to shove the DIN rubber housing on the cable before soldering the connector.

My monitor has the DIN variant of the TTL RGB, other monitors may have the 9-pin D SUB. Note the absence of SCART type connector.

In the end, contrary to all past experiences, my cable worked on the first go.

The information is not too hard to find out but here are the pinouts anyway:

Euro PC monitor pinout at the back of the computer:
1 Ground
2 Ground
3 Red
4 Green
5 Blue
6 Intensity
7 Monovideo
8 Horizontal Sync
9 Vertical Sync

Commodore 1084S TTL RGB (DIN 45326) at the back of the monitor:

1 Status comp
2 Red
3 Green
4 Blue
5 Intensity
6 Ground
7 Horizontal Sync /CS
8 Vertical Sync

I connected everything directly to their corresponding pins. I connected the two grounds from the Euro PC to the one ground pin of the monitor. The "status comp" I connected to the "Monovideo".

2 comments:

  1. I've put together both a SCART and a TTL cable, and both do work. However, you get the brown color only with TTL, SCART shows dark yellow instead.

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  2. Do you have the schematics for the scart cable?

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