Search and Track Receiver:

Model: L22M  

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L22M in Pouch

L22M in convenient carrying pouch.


  • All in one unit:
    • Search Receiver for Magnetic or Transmitter (ELF) Pigs.
    • Real Time Tracking AGM Receiver for Magnetic and ELF.
    • Standalone precision AGM for Magnetic and ELF.
  • Real Time Tracking of inspection tool or Search Receiver for a stationary pig.
  • Dual Channel (simultaneous Magnetic and 22Hz ELF) Real Time Pig Tracking.
  • Standalone AGM records simultaneous Magnetic and ELF channels for up to 570 hours.
  • Multi-frequency ELF receiver. Can be tuned to any Frequency in range: 15Hz to 30Hz.
  • Simulataneous Multi-Frequency monitoring in Range 15Hz to 30Hz
  • Works with ALL transmitters (pulsing, coded or continuous) in frequency range 15Hz to 30Hz.
  • Tracking Data are saved via wireless link to laptop for playback at a later time.
  • Equipped with fast GPS receiver.
  • Provides AGM reference data with GPS precision time accuracy.
  • Search Mode to assist in locating a stuck 22Hz (ELF) or Magnetic pig.
  • Stand-alone Search operation does not require a computer.
  • Sharp Graphics Display with backlight for easy pig signature identification.
  • User selectable Signal Level Threshold for audio alerts.
  • Audio Alerts using a Wireless (Bluetooth ®) headphone or earphone same as used with cell phones.
  • True one piece design uses internal sensor and provides freedom from wire/cable clutter.  An optional (extra cost) connector for an external sensor is available.
  • Easy Single button menu driven operation. Uncomplicated, intuitive, and easy to use.
  • Firmware can be up-graded via Bluetooth ® wireless connection.
  • Compact: size (L-W-H) 9.25" (24cm) - 3.25" (8.5cm) - 5.25" (14cm)
  • Weight  2.9 lbs or 1.32 kg with batteries.
  • Powered by a two D cell alkaline battery, gives about 200 hours of operation.
  • Very competitively priced. (Call for current price and availability)

The All -In-One L22M fills a need for pig locating, tracking, and AGM Recording.  Actively track your ILI tool in Real Time, while automatically recording all data to your laptop's hard drive.  As the L22M uses GPS timing, the saved data can be played back after the inspection run and precision AGM data can easily be extracted with a minimum of effort.

Works with Magnetic tools or ELF transmitter. Most legacy transmitters work at 22 Hz the L22M can be tuned to detect any frequency in the Frequency Spectrum 15Hz to 30Hz or it can simultaneasouly monitor the entire spectrum (15Hz to 30Hz). The L22M is ready to work with a new class of multi-frequency transmitters or legacy transmitters ensuring your investment in modern technology.  AboveGroundMarkers.Com LLC's  AGM's have always been tunable and ready to handle multifrequency transmitters since 2004 !  

Use the L22M to confirm the ILI tool's 22Hz transmitter is working, and should it happen that the pig gets stuck, the L22M can be used without a computer to search for the pig.

To assist in the search process, the L22M has a sharp high contrast display and uses a wireless headphone or ear piece (as used with cell phones) to give audio alerts when a signal has been located. NO computer is needed when searching for a stationary (stuck) pig.

The L22M has the very latest electronics and the receiver is designed to  minimize  false alerts, better than any other receiver on the market.  The uncluttered headphone connection allows the user the freedom to concentrate on walking safely on the pipeline right of way, avoiding snakes, pot holes, and other obstacles.

The other unique feature of the L22M is it can also be used to search for a stationary Magnetic (MFL) tool, and last I checked this is the only search receiver that has this ability.

Real Time Pig Tracking. ( also known as remote viewing)

Sit in the comfort of your truck with the L22M outside on the pipeline right of way.
Watch the pig pass in Real Time and automatically record the data to your laptop.  Wireless connection uses Bluetooth ® and depending upon the nature of the terrain can connect up to 300 feet from the truck.
If  internet/email service is available in your truck you can send the complete pig passage data as an email.  

Realtime Pig Tracking 

Simulataneous Frequency Monitoring of ELF channel.

multi frequency reception

AboveGroundMarker's AGM has had tunable ELF and simulataneuous ELF channel montoring since 2004 (that's 8 years).  This feature has also been included in the new L22M Search and Track AGM Receiver.

 The above image shows the Real Time Pig Tracking reception of three different frequencies by color; Red = 15Hz Green = 22Hz and Blue = 25Hz.  The frequency range for the L22M is 15Hz to 30Hz in 0.5Hz steps.

New Feature!  AGM Recording.

AGM RecordingSelect AGM Recording

agm_recording_22Hz pigThe display is updated with Type of Event and UTC time of that event.

The L22M records both Magnetic and 22Hz (ELF) to on board memory for up to 570 hours in multiple (1000's) recordings.  The Recorded data is referenced to UTC (GPS) time so any point of interest in the data can be used as a true AGM time reference point.

While recording the L22M reports ELF or Magnetic events to the LCD Graphics display.  After a pig passage these events can be viewed on site without a computer   to confirm the data has been recorded, and can be downloaded to a PC at a later time.

22Hz passReview the event on site without a computer.

ELF Pig Passage Time Scale is accurate UTC (GPS) time.  The well defined NULL tells us when the pig's transmitter was under the L22M AGM. IN this case the pig passed at 16:52:30 . A more precise time can be viewed by connecting to the L22M and viewing the data. The exact passage time is 16:52:30.95 2011/December/16.

The playback program shows a list of recordings with Start and Stop Times. When a Recording is selected the Event List is populated and then it's just a matter of clicking the event to see the passage.  This software is included in the price.

passage playback on pc


Sharp Transreflective Graphics Display.

Direct Sunlight

The above image of a 22Hz signal is very sharp even in midday blue sky Texas sun.  This display loves the sun and does NOT turn black as is the case older displays.  The Transreflective technology means this display uses light from both directions,  existing light for daytime viewing or backlight for night viewing.

Backlight for night time tracking. Simple and easy to locate the NULL of a 22Hz transmitter.

Direct Sunlight
Sharp high contrast "Transreflective" LCD display in direct sunlight. It will not turn black as is the problem with other LCD displays. This photo after 3 hours in blue sky noon day Texas sun.

Magnetic SignatureLocate a Magnetic Tool


Pulsing 22Hz TxPulsing 22Hz Transmitter (slow moving pig)


Portable:  Size (L-W-H) 9.25" (24cm) - 3.25" (8.5cm) - 3.25" (8.5cm)

Weighs just 2.9 lbs. (1.32 kg) with batteries.

A truly portable search receiver that gives the user the freedom to move around.

No longer do you have to lug 14 lbs. of legacy wired clutter along the pipeline right of way, like some old technology receivers that use  27" long antenna weighing 6 1/2lbs,  with a 7 1/2lb receiver, cables and  headphones. 

This unit is small and light (<3lbs) and will do much more than receivers costing almost twice the price.


©Copyright 2011 Hans Wedemeyer, Houston, Texas, U.S.A. All Rights Reserved.