The extraction bucket position in the Fermilab Booster is controlled with a cogging process that involves the comparison of the Booster RF count and the Recycler Ring revolution marker. A one RF bucket jitter in the extraction bucket position results from the variability of the process that phase matches the Booster to the Recycler. However, the new slow phase lock process used to lock the frequency and phase of the Booster RF to the Recycler RF has been made digital and programmable and has been modified to correct the extraction notch position. The beam loss at the Recycler injection has been reduced by 20%. Beam studies and the phase lock system will be discussed in this paper.