With the convergence of service providers, most now offer multiple products and it is not uncommon for your cellphone provider and ISP to actually be the same company.  That lets those businesses offer an app to allow you to control your PVR with your phone from anywhere you can get a signal.  There are however those who do not have the proper phone or plan or even matched providers which leaves them on their own … until now.  Hack a Day has posted a project on how to build an ethernet connected IR transmitter so you can remote control your home theatre or anything else with an IR receiver no matter what service or products you happen to use.

Control your AV system from anywhere - Systems 2

"Using IR repeaters for larger home theater setups is not uncommon, but they usually are quite simple. A series of IR receivers are placed throughout a home, all wired to repeat the signals in a central closet where all of the AV equipment is located. [Bill] constructed a solution that works much like a standard IR repeater setup, however his requires no receivers, and it can be used anywhere in the world, provided you have Internet access."

Here are some more Systems articles from around the web:

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