If you haven't already I encourage you to check out my previous post to get the full context of what this post is about. To summarize I'm making a solution for controlling my telescope from my Windows Phone and this post describes the hardware interface. The phone is going to communicate with the telescope over Bluetooth. The Bluetooth tranceiver from the post on controlling the car with the phone is being repurposed in this post. I'm constructing this circuit on a breadboard. If you would like to follow along with this project but don't want to assemble a bluetooth/serial adapter yourself a fully assembled circuit can be purchased at online retailers such as Amazon.com for 50-80 USD. I've not used these receivers myself and can't provide any information on changing settings on them.