New Microbee with a 1217 colour board

[CheshireNoir]

Howdy folks,
Yep. I have yet another Microbee. I went from none to many in only a few years!
This new one has a 1217 colour board fitted. Now I can get the pinout from the schematics (done!) but I'm not entirely sure what I can connect it to. Looks like TTL, but CSYNC and EGA style levels? 
Can anyone give me guidance on what I can connect this to? Does it correspond to a video standard used elsewhere in the industry such as CGA or EGA? I have access to many TTL or TTL compatible devices I can test with.
(I have one of Necroware's MCE Adapters, plus a 15KHz monitor plus a GBS Control, so I hame most bases covered)

Cheers and thanks in advance!
(I haven't even fired it up yet. I only got it tonight)

John

[CheshireNoir]

Somewhat related, how does one go about opening a Microbee Disk System? (Model SBC01). I've removed the 4 screws on the back. Is it just a matter of prying the two halves apart? (The plastic is insanely brittle so I want to be super careful if that's the case)
(If I missed a previous answer, I did do some googling but couldn't find any useful hits)
I'm guessing there's a non zero chance of RIFA caps in a system of this vintage...

John

[ChickenMan]

There are 2 small black headed screws in the front panel to also need to remove. Then take the front panel off and turn the unit upside down and GENTLY lift the 2 halves apart.

The power supplies differed with time, some have RIFA's some dont.

[CheshireNoir]

Thanks Chickenman,
I didn't even spot the front screws! I'll have a look-see what needs to be done in them. (I actually have three now.)

John

[Ernest]

Hi John, The Colour output on this board is close to the CGA standard but not quite.
There were two versions of this, one was straight TTL the other had half intensity RGB outputs.
Works with adaption through a GBS converter to VGA, also not too difficult to interface to an old RGB TV monitor.
I have successfully run on either with my Standard Microbee with a MB1217 colour board.
Let me know if you need a hand.

Ernest

[CheshireNoir]

Thanks Ernest,
I need to pop the board anyway. I'll have a look at which revision I have. She's not booting quite right, and, of course, the keyboard is "not well" :-D

Cheers!

John

[CheshireNoir]

Mine is a 1217-54, so the earlier revision. I assume this won't have the multilevel output?
Looking at the schematics again, they seem to be for a 9 pin connector, whereas this board has a 15 pin connector. Is there a pinout for the 15 pin connector anywhere?

Cheers!

John

[ChickenMan]

I've recently got the documentation for the 15 pin colour connector, will scan (after I find it) and put in the Repo.  Will let you know when done.

UPDATE:
Found, scanned and I put the colour_15_pin_socket_connections.pdf  in the Microbee\Documentation\Articles\Technical folder

[Ernest]

"Mine is a 1217-54, so the earlier revision. I assume this won't have the multilevel output?
Looking at the schematics again, they seem to be for a 9 pin connector, whereas this board has a 15 pin connector."

The original MB1217 board only used 9 pins of the 15 pin connector. so only the used pins were shown on the schematic.
The latter version use some of the pins not originally used to keep compatibility.
The latter version had the circuit built in for taking the RGB high intensity and the RGB low intesity outputs and put then together to give a three level analog type output suitable to analog RGB monitors.
There was a circuit diagram around that enables this adaption to be done externally, I have a small plugin box that goes between the 15pin output and goes to a SCART connector of an old Monitor TV which works a treat.
Call me if you would like to borrow it for testing, assuming you have a SCART input monitor/TV to plug it into.

Ernest

[CheshireNoir]

Thanks Chickenman and Ernest,
Lots for me to explore :-)

John