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Found these inside a non-working 71B
03-10-2018, 02:20 AM (This post was last modified: 03-10-2018 02:34 AM by Paul Berger (Canada).)
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RE: Found these inside a non-working 71B - What are they?
(03-10-2018 02:03 AM)MikeSD Wrote:  
(03-09-2018 11:12 PM)Paul Berger (Canada) Wrote:  starting from the left there should be wires from the board to the first 8 pins and then one to the far right. +5V is the far left followed by the four bus lines, then *str (strobe), C/D, and Din. The far right is GND. The connection you are pointing at would be B0.


I need to get home and look at it again.the broken wire might go to the 4th from left. Something else noticed in the photo. Pin 9 on RAM board looks a lityle brown. And the far right pin looks to have a bubble of solder at 71 board. mihgt have had a short at one time

That looks like flux residue on pin 9 flux residue is usually not an issue. That blob of solder where the right pin (GND) connects to the board looks like bad soldering, could be a problem.

One of the modules should have a wire to pin 8 (Din) from the board and then pin 9 (Dout) of that module should connect to 8 of the next one and so on. This is the daisy chain that is used to configure the memory devices.

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RE: Found these inside a non-working 71B - What are they? - Paul Berger (Canada) - 03-10-2018 02:20 AM
What's U10? - Dave Frederickson - 03-15-2018, 03:43 PM

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