Mid-Range Sonde

Mid-Range Push-Rod & Camera Sondes

  • Mid-range sondes in three industry-standard frequencies
  • 512 Hz (FD-20), 8 kHz (HD-40) and 16 Hz (LD-9)
  • Locates up to ~21 ft in non-metallic pipe
  • FD-20 reads ~14 ft through cast iron
  • LD-9 (16 Hz) works through ductile and steel pipe
  • Built for push rods, sewer cameras and crawlers

Prototek’s Mid-Range Sondes cover the everyday locates that sit between the compact tight-space sondes and the deep long-range units. The family spans all three industry-standard frequencies so you can match the sonde to the pipe material and the depth in front of you.

The FD-20 is a 512 Hz sonde that reads roughly 14 ft through cast iron and 20 ft in non-metallic pipe — the go-to for push rods and sewer cameras. The HD-40 is an 8 kHz multi-frequency sonde reaching ~21 ft in non-metallic lines, and the LD-9 runs at 16 Hz to push a signal through ductile (~9 ft) and steel (~5 ft) pipe where higher frequencies can’t.

The FD-20 and HD-40 share a compact 3/4″ x 4″ body on a single AAA cell; the larger LD-9 (1″ x 7″, 3 x AAA) suits 4″ lines and up and rides equally well on a push rod or a crawler.

Key Features

Three frequencies 512 Hz, 8 kHz and 16 Hz to match line material and depth.
FD-20 512 Hz; ~14 ft in cast iron, ~20 ft in non-metallic; 3/4" x 4", 1 AAA.
HD-40 8 kHz multi-frequency; ~21 ft in non-metallic; 3/4" x 4", 1 AAA.
LD-9 16 Hz multi-frequency; ~9 ft ductile / ~5 ft steel, ~12 ft non-metallic; 1" x 7", 3 AAA.
Metallic-pipe reach The 16 Hz LD-9 locates through ductile and steel pipe.
Versatile mounting Push rod, sewer camera or crawler depending on model.
Replaceable AAA cells Field-serviceable power across the family.

Specifications

Models & Frequency

FD-20512 Hz, 512 Hz Sonde receiver
HD-408 kHz, Multi Frequency Sonde receiver
LD-916 Hz, Multi Frequency Sonde receiver

Range

FD-20~14 ft in cast iron, ~20 ft in non-metallic
HD-40~21 ft in non-metallic (not metallic-compatible)
LD-9~9 ft ductile / ~5 ft steel, ~12 ft non-metallic

Physical

FD-203/4" x 4" L, 3.3 oz, lines 3" and up
HD-403/4" x 4" L, 3.3 oz, lines 3" and up
LD-91" x 7" L, 11.7 oz, lines 4" and up

Power & Use

FD-20 / HD-401 AAA — push rod or sewer camera
LD-93 AAA — push rod or crawler

What's in the Box

  • Mid-range sonde in the selected model (FD-20, HD-40 or LD-9)
  • Battery (1 AAA; LD-9 uses 3 AAA)
  • End cap
  • Push-rod / camera / crawler mounting options per configuration

Interested in the Mid-Range Sonde?

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