The SubZero fix is the most reduced and reliable RS2004FS shutdown fix on the market. That means that it shuts down all of the laser lens driver chip's outputs completely as soon as it detects a MechanicsController lockup.
As soon as the interrupt line between the MechanicsController and the DigitalSignalProcessor in the psTwo goes low, the capacitor in the SubZero fix circuit starts to discharge. If the interrupt line does not go high within 50miliseconds - the capacitor discharges and mutes the RS2004FS completely. By doing that it prevents ANY dangerously high currents resulting from the lockup to flow thru the lens coils. The lens coils are now 100% immune to the dangerous MechanicsController lockups.
It is the only fix of this kind that does NOT use any programmable ICs like the PIC12C508. It consists of exclusively passive components, 3 in total to be exact. By that we reduce the minimum install solder point count to 3, which speeds up the install and most of all - keeps all possible sources of error and malfunction to a minimum. The 3 reliable passive components are also the cheapest implementation of the fix, making it very competitive in price.
Download Install Diagram
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