Long Range Sonde

Long-Range Crawler Sondes

  • Prototek's deepest sondes for long, challenging locates
  • Three frequencies: 512 Hz, 8 kHz and 16 Hz
  • Up to ~55 ft range in non-metallic pipe (HD-80)
  • FD-40 reads ~30 ft through cast iron
  • LD-14 (16 Hz) drives through ductile and steel pipe
  • Built for crawlers in lines 6" and up

Prototek’s Long-Range Sondes are built for the deepest, most demanding locates — the jobs where the signal has to punch through depth, ground conditions and pipe material to reach the surface. All three industry-standard frequencies are covered so you can be ready for any environment.

The FD-40 is a 512 Hz sonde reaching roughly 30 ft through cast iron and 40 ft in non-metallic pipe. The HD-80 is an 8 kHz multi-frequency sonde with the family’s longest non-metallic reach at ~55 ft, and the LD-14 runs at 16 Hz to drive a locatable signal through ductile (~13 ft) and steel (~7 ft) pipe.

All three share a rugged 1-1/2″ x 10-3/4″ body (2–3 lbs) powered by four C-cells for long runtime, sized for lines 6″ and larger and at home on a crawler for mainline work.

Key Features

Three frequencies 512 Hz, 8 kHz and 16 Hz for deep locates in any environment.
FD-40 512 Hz; ~30 ft in cast iron, ~40 ft in non-metallic; 512 Hz Sonde receiver.
HD-80 8 kHz multi-frequency; ~55 ft in non-metallic — the longest in the line.
LD-14 16 Hz multi-frequency; ~13 ft ductile / ~7 ft steel through metallic pipe.
Long runtime Four C-cells power extended mainline inspections.
Rugged body 1-1/2" x 10-3/4", 2-3 lbs; lines 6" and up.
Crawler-ready Designed to ride a crawler for deep mainline locates.

Specifications

Models & Frequency

FD-40512 Hz, 512 Hz Sonde receiver
HD-808 kHz, Multi Frequency Sonde receiver
LD-1416 Hz, Multi Frequency Sonde receiver

Range

FD-40~30 ft in cast iron, ~40 ft in non-metallic
HD-80~55 ft in non-metallic (not cast-iron compatible)
LD-14~13 ft ductile / ~7 ft steel

Physical (all models)

Dimensions1-1/2" x 10-3/4" L
Weight2 lbs (LD-14: 3 lbs)
Minimum line size6"

Power & Use

Batteries4 C-cell
Best useCrawler

What's in the Box

  • Long-range sonde in the selected model (FD-40, HD-80 or LD-14)
  • 4 C-cell batteries
  • End cap
  • Crawler / push-rod mounting options per configuration

Interested in the Long Range Sonde?

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