That previous thread is a user with Uniden scanners, which have an external speaker jack therefore any speaker will do. You're specifically asking how to connect a motorola speaker to a scanner with an earphone jack and that's where the problem is. RadioShack scanners and others don't have a speaker jack but only a headphone jack. Therefore the speaker must be amplified (powered from outside source) or you'll audio will be 90% or so less if the speaker is not amplified due to the hearing protection for earphones. Now, there are mods, for Pro-96 specifically where you take a piece of wire make a loop and put the jack through it and in the scanner that way it ellimiates the protection that makes it quieter. But I would'nt do that. I would suggest you do get a motorola speaker, but make sure it is an amplified model and that you know how to mod it to use with a wall wart or car lighter plug, if in fact your scanner only has a limited earphone jack and no speaker jack.