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Lets see if anyone can identify this little circuit board





Lets see if you can identify this little board.

The board referring to is the little circuit board with tiny IC next to the VIC-II chip (big black chip to the right with the white gue) of the Commodore 128 (not 128DCR). It sits directly over the chip at U29.


None of this "Go look it up" and similar type of responses. It would be totally useless because you can't Google search something if you don't know what it is to call it and search results would be totally useless. Such responses like "Go search for it" isn't going to help because A) you don't know and B) It doesn't answer the question because Google and other search engines would be too inundated with non-relevant results that it would take longer than it too in the 1990s to save the money and go to every single Commodore club and user's group on the planet and often you'd get the answer to it by someone in any of the local clubs within 100 miles.



Added notes:


The chip on the little board is a National Semiconductor DM74LS74AM.... it is a small outline package TSOP?.


Datasheets states it is a Dual Positive Edge Triggered D-Flip Flop.


The board itself does not replace the chip under it. That chip is still there.


The chip underneath this little board should be a HD7406 or like 7406.


When I wrote U29, I mean U29 not U28.



From the little circuit board, it red wire connect from it to ground plane under the 14.3181818 MHz crystal and a blue wire connects from the little circuit board to a solder pad next to what looks like a green resistor (choke?) where the solder pad has a trace that appears to connect to the 8701 (U28) or VIC-IIe at pin 29 (if I read the pinout correctly like I do a VIC-II 40-pin but that the chip has 48 pins (4 rows pins longer).


I hope this helps somewhat.


If Bill Herd, lets see if you might now.