JW Fishers Proton 5 Magnetometer Features
• Automatic / Manual Tuning Feature
• 1 nT Sensitivity
• 1,500 Foot Detection Range
• Breaks down for easy transport (case included)
• 6” LCD Screen with Full Function Menu such as POL Times, Sensitivity & Alarms
• All connections on side of control box for inclement weather operation
The JW Fishers PROTON 5 is a fifth-generation proton magnetometer from JW Fishers. It is a top-performing microprocessor-driven marine magnetometer detection system. With a one Nano -Tesla (nT) sensitivity, it has the maximum usable sensitivity for a towed proton precession magnetometer. A two-second cycle time gives a strong return signal and is fast enough to detect even small iron/steel targets. The PROTON 5 features a triaxial noise-cancelling sensor that allows omnidirectional towing without heading error or dead zone. The system is fully digitized and displays the current 5-digit measurement on an easy-to-read 6 inch LCD screen that is backlit for night operations. Up to 80 of the previous measurements are also displayed graphically in a history plot on the LCD. With the optional altimeter, the distance off the bottom of the towfish is displayed. User-friendly menus allow easy configuration of all operation settings and system tuning directly from the topside control box. An adjustable audio alarm lets the operator decide how much of a change in the baseline reading will cause the alarm to fire.
The towfish has excellent hydrodynamic characteristics, moving smoothly through the water at tow speeds up to 10 knots. The Fish can be towed at almost any speed, but A 2-3 knot tow speed is recommended for small targets. With the optional UA-3 Altimeter, the Proton 5 can maintain a precise distance off the bottom. For deepwater towing, the Fish is towed behind the optional DDW-1 Deep Dive Wing depressor. The collapsible PROTON 5 towfish easily fits into a watertight Pelican® case. Modular construction allows easy field repair, should it ever be necessary.
The base system includes a 200-foot depth rated towfish, 150 feet of Kevlar reinforced tow cable, and a topside control box. Optional USB data output and Tracker 3 software are available, which allow the mag readout to be displayed on a laptop computer, along with GPS position coordinates. The target position is displayed and recorded on the computer. An optional Microsoft Surface ® tablet can be mounted in the control box lid, eliminating the need for a separate laptop computer making it a streamlined package.

PROTON 5
The PROTON 5 is a proton magnetometer that was specially designed for underwater salvage work. The system consists of a Control Box, a 150-1,000’ cable and a towfish.
CONTROL BOX – The topside Control Box consists of an Underwater Kinetic case that houses the display, control electronics and interface connections between the towfish, GPS receiver (optional), PC (optional) and batteries (2 x 12v deep cycle marine type). The
(optional) Microsoft Surface tablet PC mounts directly in the cover of the case.
CABLE – The 150-1,000’ tow cable consists of multiple wire pairs and coax cables protected by a Kevlar reinforcement braid encased in a highly abrasion-resistant urethane jacket.
TOWFISH – The towfish is 52 inches long and has a watertight compartment that contains the sensors and the electronics necessary
for processing the signal before sending to the control box. The Fish has four fins for stability and is weighted for negative buoyancy. The materials used in the construction of the Fish were specifically selected for high impact resistance and low maintenance. It can be separated in the midsection for easy transportation.
Proton 5 Range Chart
Object | Near Range | Far Range |
---|---|---|
1 gallon can | 2 nanoteslas at 12’ | |
5 gallon can | 2 nanoteslas at 18’ | |
55 gallon drum | 2 nanoteslas at 45’ | |
Small Plane | 25 nanoteslas at 20’ | 2 nanoteslas at 50’ |
6” pipeline | 200 nanoteslas at 20’ | 2 nanoteslas at 100’ |
12” pipeline | 350 nanoteslas at 20’ | 2 nanoteslas at 175’ |
Large anchor | 500 nanoteslas at 50’ | 2 nanoteslas at 200’ |
Medium ship | 1500 nanoteslas at 100’ | 2 nanoteslas at 1000’ |
Large ship | 2000 nanoteslas at 100’ | 2 nanoteslas at 1500’ |

• Sensitivity (menu adjustable) – resolves 1 nT
• Maximum detection distance – 1,500 feet
• Cycle time (menu adjustable) – 2 to 10 seconds
• Tow speed – 1 to 10 MPH
• Maximum operating depth (standard unit) – 200 feet
• Input voltage (two marine or automotive batteries) – 24 VDC
• Power consumption – 40 watt
• Fish – 52”L x 6”D – 45 lbs.
• Control box – 14”L x 10”W x 6”H – 7.5 lbs.
• Tow line – .375”D x 150 feet to 1,000 feet – 15 to 100 lbs.
• Carry case – 37”L x 27”D x 14.5”H – 38 lbs.
- a 200-foot depth rated towfish
- 150 feet of Kevlar reinforced tow cable
- topside control box
• USB data output and GPS input (includes GPS receiver)
• Tracker 3 Software display package (includes boat tracking)
• UA-3 altimeter
• Deep Dive Wing (downrigger)
• 1,000 depth capability
• Longer cable lengths and CMS cable management system
• Microsoft Surface® tablet mounted in the control box lid
• Rugged, splash proof Panasonic Toughbook® laptop
JW Fishers Proton 5 Magnetometer
Boat towed magnetometer for ferrous metals with 150 feet (~45m) of cable, cable connector, 500′ depth rated towfish, waterproof Pelican® transport case, 6in. LCD display built into the control box and auto-tuning.

Proton 5 Accessories
Extra Cable: ADDITIONAL cable up to 1,000 feet (~300m)
UA-3 altimeter: Measure distance from tow fish to the bottom of the seafloor.
USB data output: Allows detector output to be sent to the computer (Includes GPS).
Housing: 1,000 foot (~300m) depth rated housing.
Tracker 3 Software: Software installed on a Dell® laptop for data display, storage & boat tracking. (requires USB ).
DDW-1 (Deep Dive Wing): Depressor wing allows for deeper towing with less cable.
GETAC® Laptop: S410 (or equivalent) semi-rugged 14″ laptop, MIL-STD 810H certified.
Tablet: 10.8″ Windows® based tablet mounted into control box.
CMS-1: Cable management system for up to 500 feet (~150m).
CMS-2: Cable management system for up to 1000 feet (~300m).
