Review on Sperry Instruments CS61200P Electrical Circuit Tester by James Roberts

This tool really works. Initially, I had the same problem as many other reviewers: all the switches in my box seemed to have a signal and I couldn't find the right switch. I was ready to box up and ship the device back, but decided to take a closer look and follow the instructions more closely. Instructions are not included and must be downloaded from the Sperry website (a quick google search for the model number led straight to the instructions). A few points to make the tool work.1. Ignore the 60Hz hum/howl the receiver picks up each time it approaches the control box. I finally concluded that this noise was coming from the AC lines in the switch box and in my case all the switches in the box were making this noise at different levels. At first I took this noise as a signal coming from the transmitter, because the level of each breaker is different, which is why it seemed to me to be the signal from the transmitter. It would be easy to filter out this noise with a few extra components inside the instrument, but that would probably increase the cost a bit and obviously the main purpose of this instrument is low cost.2. The LED meter is useless as the 60Hz noise mentioned above will cause this meter to trip and for most circuit breakers this meter will be out of range.3. It is very important to properly align the probe attached to the receiver. It must be held perpendicularly against the face of the switch.4. Listen for a distinct "beep-beep-beep" tone mixed with 60 Hz noise. When you place the wand on the correct switch, this beep will be the loudest. In my case you could hear 1-2 adjacent switches beeping, but not as loud as the right switch. Giving this tool 4 stars is probably being very generous, but it really works and the price is very good. I would suggest that more expensive instruments have a suitable filter to get rid of the 60Hz noise. As a casual user of this tool, I'd rather save a few bucks, but if you use this tool frequently or are a professional electrician, this tool may not be for you.