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

Posted: 03 Feb 2021 01:38
by DominoTree
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What's this sticker on the front?

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We have some interesting ports here

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

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It boots and looks good!

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The whole setup

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Demo unit 5 sent to B&C Computervisions?

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It's plugged into the shifter socket!

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This little connector appears to be made of some sort of resin

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Front side of the display connector

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

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

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And more bodge work

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

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

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The remote control... made of real wood!

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

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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!

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

Posted: 03 Feb 2021 07:50
by exxos

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

Posted: 03 Feb 2021 11:14
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.

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

Posted: 03 Feb 2021 11:38
by Steve
Will be nice to see some Atari overlaid graphics, perhaps you could make something and upload to youtube :)

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

Posted: 03 Feb 2021 12:42
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?

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

Posted: 03 Feb 2021 13:40
by stephen_usher
Wasn't the SST the board which killed Gadgets by Small due to legal costs over defective chips?

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

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

Does that machine have the JRI4096 board?!

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

Posted: 03 Feb 2021 16:27
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

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

Posted: 03 Feb 2021 16:29
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.

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

Posted: 05 Feb 2021 20:19
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?