Sniffer Probes with Contact Tip Probe The PS-500 is a Near Field Probe set consist four probes and a custom storage case. Performance and ease of use were designed into this product. The unique design allows easy access for tight or hard to reach places while reducing the effect of hand position or cable placement. The fine tip and the contact tip probe are precision E-field probes that features the ability to singularly identify a problem trace or pin. The fine tip probe is designed to be extremely sensitive to distance from the source which allows easy discrimination between traces on a PCB. The unique patented design allows measurement on individual traces as narrow as 3 mils. The contact tip probe allows direct electrical contact with the circuit. It has wider frequency range than the fine tip probe. Just like the fine tip probe the contact tip probe allow finding noise source to a trace or pin. The broadband probe is designed to identify E-fields over a broad frequency range