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Mac 128k analog board recap, old C6 soldered with resistor
Posted by: captjon320 on 2023-10-23 18:10:28
Hello all,

I'm recapping three Mac 128k analog boards. I took the easy path and ordered the cap kits from Console 5. I am on the 2nd board and noticed that the old C6 (22uF 50V) cap has a resistor attached to it. The other two boards did not have the resistor attached and the old capacitor values are the same on all three. The replacement cap is a 22uF 63V, which I assume is due to newer vs older part availability.

I am leaning toward not putting the resistor on the new cap, but wanted to ask the community for input as well.
C6.jpg
Posted by: tvj on 2023-10-23 22:11:08
What was the resistor connected to? It seems to be pulling down that part of the circuit for whatever reason. Are the boards the same revision? I can't imagine it was placed there randomly.

Edit: Oh, look at the boards closely directly next to C6. The very first early 128k boards have that resistor, but later boards added a spot on the circuit board for a proper placement.
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