Was looking over the dead LC III 25MHz, and saw an empty capacitor spot (C17). So I thought, "did I forget to put a cap there during recap?" I checked it with the other LC III (a 33MHz) that works. C17 spot is also missing on the other board.
Then I looked over the two boards, and I found a lot of dead end areas. This one on the top of the board in particular as a 10µf capacitor was recapped in this area. Which I have a question...
I can not see where the trace goes because "U32" is covering it. But from that I can make out, it loops back to C18. And the middle trace goes to an empty pad area.
Does that loop trace goes under the VRAM Chip at location U32? I have a feeling that it does not.
And there are other funny areas I found looking for dead traces. Underside of board R71 is one such area that goes to nowhere as there is no R71. Again on the underside R88 is another, a trace comes out of it to a junction to the other side BUT there is another trace that breaks at that point because R88's trace is in the way. I found several funny spots like that, confirming them with the working LC III.
So... why so many funny areas? This makes looking for broken traces when one runs into a dead end spot. An in the case of C18, it is necessary or can it be removed? That depends if the trace goes under U32, which I can not see.
Then I looked over the two boards, and I found a lot of dead end areas. This one on the top of the board in particular as a 10µf capacitor was recapped in this area. Which I have a question...
I can not see where the trace goes because "U32" is covering it. But from that I can make out, it loops back to C18. And the middle trace goes to an empty pad area.
Does that loop trace goes under the VRAM Chip at location U32? I have a feeling that it does not.
And there are other funny areas I found looking for dead traces. Underside of board R71 is one such area that goes to nowhere as there is no R71. Again on the underside R88 is another, a trace comes out of it to a junction to the other side BUT there is another trace that breaks at that point because R88's trace is in the way. I found several funny spots like that, confirming them with the working LC III.
So... why so many funny areas? This makes looking for broken traces when one runs into a dead end spot. An in the case of C18, it is necessary or can it be removed? That depends if the trace goes under U32, which I can not see.
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