The Most Affordable Locating Solution

Septic Tank pumpers nationwide rely on Prototek flushable transmitters to take the guesswork and expense out of locating septic tanks. Or taped to a push rod, they do a great job exploring small lines and drain field laterals. Here’s how to use flushables.

These sturdy units are hermetically sealed and won’t leak in the most hostile environments. Although you can’t change the batteries, they are reusable – turn them off after a locate to use again later.

Read more about the new style “Push Button” flushables that are now shipping.

Download instructions on how to use push-button flushables

** Did you send in recycles and got the envelope back?


  •  Works with:  AR-1 only
    (replaces the AT-12)
  • Frequency:  223 kHz
  • Tone:  B
  • Battery Life:  12 hours
  • Range/cast iron:  N/A
  • Range/non-metallic:  Over 12 ft

  • Works with:  FR-1, LF2000, LF2200
    (or any 512 Hz receiver)
  • Frequency:  512 Hz
  • Tone:  C
  • Battery Life:  4 hours
  • Range/cast iron:  8 ft
  • Range/non-metallic:  12 ft

We guarantee a shelf life of 12 months; beyond that is unpredictable.  Store them in the refrigerator for longest life, but let them warm up before using.
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 one of these types; many are available either way. Which tone should you choose? Here are some considerations about each type:

C – Continuous or “Solid” Tone

• available on almost all Prototek transmitters
• best to use for determining precise depth
• compatible with most other manufacturers’ equipment

• harder to distinguish signal from interference
• shorter battery life

B – Beeping (on/off) Tone

• easier to distinguish signal from interference
• longer battery life

• difficult to use for determining depth
• won’t work with LF2000 or LF2200, or many other manufacturers’ digital equipment