Got a MEGA ST2 today... with a fascinating JRI Genlock system

General discussions or ideas about hardware.
DominoTree
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Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by DominoTree »

1.jpg
What's this sticker on the front?

2.jpg
We have some interesting ports here

3.jpg
Better view of the ports along with the connector tying into the native display output

4.jpg
It boots and looks good!

5.jpg
The whole setup

6.jpg
Demo unit 5 sent to B&C Computervisions?

7.jpg
It's plugged into the shifter socket!

8.jpg
This little connector appears to be made of some sort of resin

9.jpg
Front side of the display connector

10.jpg
Once we remove the board with the fan, conformal coating EVERYWHERE! Thick, sturdy, nasty stuff.

11.jpg
Some poor soul had to scrape all of this away and do bodge work

12.jpg
And more bodge work

13.jpg
Beneath the board, we have a bone stock MEGA ST2 rev5 with Blitter and no clock patch

14.jpg
The bottom of the board with traces, more bodge work, and our DMA chip

15.jpg
The remote control... made of real wood!

16.jpg
And here we have some sort of SMPTE interface that seems to have connections for the serial port and a mouse/joystick port?!

17.jpg
The bottom of the interface


That's all for now folks! I don't have any video hardware available to do any further testing here, but I'm hoping to get what I need to play around with this Genlock system soon!
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exxos
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

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rubber_jonnie
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by rubber_jonnie »

I saw your post on FB too, and at first I thought surely it's got to be plugged into the Megabus slot. But no!

Always nice to see unusual hardware out in the wild, and nice to see a big button Mega as well.
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Steve
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by Steve »

Will be nice to see some Atari overlaid graphics, perhaps you could make something and upload to youtube :)
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derkom
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by derkom »

Back in the day, I had a Mega 4 with a JRI Genlock board and also a Gadgets by Small SST. Very sorry I got rid of that, but it paid for my Falcon.

The JRI was a very nice board, and the overlay image quality was superb. Definitely professional quality gear.

Is this one working?
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stephen_usher
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by stephen_usher »

Wasn't the SST the board which killed Gadgets by Small due to legal costs over defective chips?
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mrbombermillzy
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by mrbombermillzy »

If Im not mistaken, theres an ST Shifter on one of those boards...

Does that machine have the JRI4096 board?!
DominoTree
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by DominoTree »

mrbombermillzy wrote: 03 Feb 2021 14:41 If Im not mistaken, theres an ST Shifter on one of those boards...

Does that machine have the JRI4096 board?!
I misspoke and said it was a DMA chip but it's definitely a shifter. The reason it's there is because the Genlock plugs into its socket on the ST, so the shifter gets moved to the Genlock and lives there
DominoTree
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by DominoTree »

derkom wrote: 03 Feb 2021 12:42 Back in the day, I had a Mega 4 with a JRI Genlock board and also a Gadgets by Small SST. Very sorry I got rid of that, but it paid for my Falcon.

The JRI was a very nice board, and the overlay image quality was superb. Definitely professional quality gear.

Is this one working?
It's working-ish. There's some signal distortion, but I have a feeling some general cleanup (cleaning/replacing pots and such) will resolve it. The MEGA is doing a few Weird Things(tm) as well but I still need to go over it too.
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mrbombermillzy
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Re: Got a MEGA ST2 today... with a fascinating JRI Genlock system

Post by mrbombermillzy »

I dont suppose all that stuff in there, or indeed time has borked the (presumably original) PSU a bit which may be causing some of the issues?

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