Oh yeah, you are absolutely correct. Just an alternative for someone that may have a DVM at home and wanted to use it. But, the ESV is the way to go. Simple, easy to use, and, what.. two moving parts... 4.8 - 6 volt switch and the TX - RX switch... but remember to check the battery often.. (based on personal experience.. )

My home DVM is a Micronta scientific type with good response AND a serial output so I can take in data to a spread sheet and plot it if I wish. Kinda neat.. but somewhat useless unless you are serious about finding those binds or smoothing out the linkage. Nerd stuff I guess.. but fun to play with on a boring rain filled day.

Dick.