CD4520 reset problem

im trying to add a reset to a CD4520 but running into an issue:

in the TKB serge uses a CD4520 to handle the vertical clock (cycling between four vertical rows of pots)
here is a relevant snippet of the schematic (as found on hyperreal)
i copy and pasted the clock input to use as the “vertical reset” and am sending that to an inverter to the bottom half reset - it works, but only once, and then not again until i power cycle. am i missing something simple here?

Pin 13 (Q3B) is an output. Tying an output of one chip to an output of another is likely to lead to unpredictable behavior (and, perhaps, damage to the chips).

If you want Q3B OR RESET IN to reset, you probably should put each signal through a diode.

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thanks, thats a good idea - the reset works on the original TKB fine, but i am injecting into that loop - ill add a diode and see if that helps

Two diodes, one on Q3B and one on RESET IN.

im adding one out of Q3B
you think the inverter output to the reset pin needs one too? its a cd4069

Yes. In your schematic pin 15 will have the same voltage as the inverter output regardless of what pin 13 is doing, because they are tied together. What you need is an OR gate, and that requires two diodes, one for each signal. See the link I posted above.