The Workhorse

Soon to be known as the FD-20 and FD-40 these transmitters are both versatile and powerful. Our new line of Durasonde Transmitters are more durable, with the same great performance and pricing as our FV series. They are currently available and coming online soon.  The FV series is being discontinued and are available while supplies last. Great for cameras without a built-in transmitter, and rugged enough to give you years of service.  Use the FV-20 in a Spring Carrier for power snaking, or taped to a jetter or push rod or other device that doesn’t subject it to heavy abuse.  The heavier FV-40 needs a camera tractor to get down the line.

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Check out these accessories:



  • Size: 3/4″ x 3-1/2″
  • Range/cast iron: 10ft
  • Range/non-metallic: 15ft
  • Battery: AAA Alkaline
  • Tone: Constant
  • Line Size: 2″ and up


  • Size: 3/4″ x 3-1/2″
  • Range/cast iron: 20ft
  • Range/non-metallic: 30ft
  • Battery: AAA Alkaline
  • Tone: Constant
  • Line Size: 3″ and up

  • Size: 1-1/2″ x 10″
  • Range/cast iron: 32ft
  • Range/non-metallic: 47ft
  • Battery: 3 “C” Alkaline
  • Tone: Constant
  • Line Size: 6″ and up
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    Please call 800-541-9123 to order
Prices apply to US orders only

  • 16 Hz – a very low frequency with the advantage that it will penetrate steel or ductile iron lines (as well as cast iron and nonmetallic). It is compatible with any gear that operates at 16 Hz.
  • 512 Hz – the industry standard frequency for locating in cast iron or nonmetallic lines. It is compatible with any other manufacturer’s 512 Hz equipment.
  • 8 KHz –  a high frequency that works in nonmetallic lines only, but is very efficient and offers good range. Works with any 8 KHz equipment.
  • 223 KHz – suitable for nonmetallic environments only. Only Prototek makes equipment that operates at this frequency (AR-1 and ATP-12).

You must match the transmitter’s frequency to the receiver’s frequency. A 512 Hz Transmitter will not work with a 223 KHz Receiver, etc.

The Range of a transmitter is the maximum distance, in feet, your receiver can be from the transmitter and still pick up a usable signal (using fresh batteries in both transmitter and receiver). The numeric part of the Part No. of every Prototek transmitter tells you what its maximum effective range is.

  • For 16 Hz transmitters, the Part No. tells you its range in steel or ductile iron lines. This range is very dependent on the wall thickness of the pipe, so the range given is pessimistic, i.e., for the thickest typical lines. Range in nonmetallic lines can be up to 3 times that in steel; the range in cast iron is slightly less than in nonmetallic.
  • For 512 Hz transmitters, the Part No. tells you its range in cast iron. You can easily determine its range in nonmetallic lines by multiplying this number by 1.5. That means the range of an FV-10, for example, is 10 feet in cast iron and 15 feet in nonmetallic.
  • For 8 KHz transmitters, the range is for nonmetallic lines only – its signal will not pass through any kind of metal. For example, the range of an HV-40 transmitter is 40 feet.
  • For a 223 KHz transmitter (ATP-12), the range is also for nonmetallic lines only. The range of an ATP-12 flushable transmitter is 12 feet.

Note: These Range distances apply to Prototek receivers only! We cannot guarantee your results with other receivers.

“Tone” refers to the type of signal emitted by a transmitter. All of our transmitters are now a continuous tone.  This is better for a more accurate locate. If you are having issues around power lines our 8 KHz, HD series transmitters are right for the job.