Search: Selecting the Search Ranges
Oligo's search range window controlls much more than the plain search ranges. By checking the "Find products in checked region(s) only" box, the software will seach in selected feature or features (you need to click the "Check Region(s)" button to select it first). With this window you may also choose the size of PCR products and prevent from finding multiple, but almost identical primers by checking the "No overlapping primers/probes" box. The options in this window are self-descriptive, but I'd like to point out on yet another nice feature: "Choose sequencing primers (or hybridization probes) every xxx nt." These are active when searching for single primers/probes, and are particularly useful when working on long sequences.