Here is a link to a discussion on another forum about improving the reception on the ET-73. It's rather lenghty, but I found it worth the read.
In a nutshell, it involves adding an antenna to the receiver. All that's required to do so is to solder a 6.5 inch piece of wire to a specific hole on the circuit board, and cut a small notch in the case to allow the wire to come out of the top of the receiver. It is a pretty simple procedure, and it really helps. Before I did this to my unit, I was limited to about 15-20' reception. Now I can use the receiver anywhere in my house.
Hope you find this helpful.
Matt
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