If you buy the Transponder and go and pick up scanner and do 2 of the interfaces, then die and fast travel.... you will lose scanner and you will lose the transponder buff making you unable to pick it up again and you will not be able to buy them again until next week, ruining your chances of getting the triumph's done.
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It won't ruin your chances, you'll just need to wait until the Scanner is next available for any regions you missed.