@gunrunnerjohn posted:Small correction, they don't monitor data packets received, only transmitted.
Distinction noted John; thanks for that! 
@GGG posted:Is this different than the other version made? That one does not work for me with a lighted lock on and I assume for a layout. It only measure transmit strength of TIU in a stand alone mode. Which is what I need for test repair. G
By "the other version" George I assume you mean the portable TIU tester designed by Adrian, and sold in kit form by rtr12? The boards I have are actually adapted from that same design. The big difference is that instead of a red and a green led; one to indicate high signal strength and the other medium strength; these boards use two separate circuits to monitor two TIU channels per board. There is a trim pot for each channel that can be used to adjust signal sensitivity. With a setting of about 3/4 turn CW, I find they trigger at a DCS signal strength of about 10-12 volts, which is a reasonable value to expect for any healthy TIU channel.
Rod
