68kMLA Classic Interface

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What is this component on the Lisa 2/10 motherboard?
Posted by: Tor on 2023-03-14 20:14:42
What is this yellow component on the Lisa 2/10 motherboard, can I find a replacement for it, or build one from discrete components?
It's located right behind the mouse connector.
Labeled "343-1003". Has 10 pins in one row. On the board it is labeled with white letters "U2".
Looks like a resistor pack or EMI filter pack, but I can't get a good measurment: it measures 0 ohms across pins 6,7,8,9, and various kiloohms across other pins.

Reason for asking: Some time ago, I bought 3 of these motherboards on ebay years aog; the component was carefuly removed on all of them, along with the expansion slots. Someone was harvesting parts for these new lisa motherboards I've seen online.


20230310_230943.jpg
Posted by: bibilit on 2023-03-15 08:58:25
Looks like a resistor pack to me.
Posted by: Tor on 2023-03-16 23:44:38
Answering myself:
It turns out this is a tiny amplifier for the video-out connector.
Has 2 transistors and few resistors and caps inside.
This component was made with discrete elements on the Lisa 2/5 motherboard; it's schematics can be seen on the "Composite Out" section of this diagram.
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