Repair of a broken MTC900 chassis

[level42]

AFAIR the 900E is actually (and strangely) the one that was aimed at the US, not Europe.

About the question: you can also use this document:

http://www.andysarcade.de/data/electronics/testing/mueter/mueter_crt_liste_2009.pdf
Find the tubes, and if they both need the same adapter than it should be pretty safe to try it.


HOWEVER.......you are probably swapping tubes with the yokes still on them and you will also have to measure the resistance of both the H and V coils of the yoke. They need to be at least a bit close....

[level42]

Yep just checked and both those tubes need the same adapter (815) and thus you. An swap them neck-wise....

The yoke issue has still to be investigated by yourself

[ckong]

AFAIR the 900E is actually (and strangely) the one that was aimed at the US, not Europe

Not quite,  the 900E came in 2 versions,  an US version and an European version. I have the European version and made today 2 working monitors with them,  with the help of 2 A50-231x tubes.   

[PaulSwan]

The 220V degauss usually doesn't care if it's isolated or not - in some games it's tapped off the line side un-isolated. The 128VAC always needs to be isolated.

AFAIK all 900 & 900E necks & yolks are generally compatible in the common S4/NE04 varieties. There are some oddball rarer ones that are not. However, there are some minor variations in the chassis componentization per tube that might cause trouble.

See http://www.zzzaccaria.com/MrDoRestoration.htm for one possible example of mismatching chassis with tube.

http://www.zzzaccaria.com/images/Projects/SuperCobraRestoration/SAM_4647w.JPG is the Hantarex doc for chassis-tube variations.

Paul.

[level42]

I think my first comment about the 900E is not entirely correct.
There is a 900E and a 900E USA.

At least, there are different service manuals for both types. I know this since I picked up a 900E last weekend and it came with the manual.

The manual didn't look familar to me so I searched on the internet and found both manuals for a 900E (the one I got) and a 900E USA.

 The mainboard number differs, one is DE2 the other DE4 but I don't know which is on which from the top of my head. Interesting fact about the one I picked up: the previouse owner put a mains cord on it with a regular plug and I saw it working at his house so without isolation transformer and on 230VAC.

As a sidenote, he also hacked on a SCART connector....