I have the single probe model similar to the 73. Cannot get a signal inside my house. If you get the 73, you'll roll over in the bed & glance at it & think everything is OK. Problem is you lost connection hours ago when the back door closed. Nothing tells you when the signal is lost. I got a 732 several months ago. I have no problem getting a signal inside the house.
Jim Sewell -- GBA Vice President, Master Judge, Contest Rep & GBA Webmaster