User's Manual
Table Of Contents
- Safety Precautions and Warnings
- Dear Customer:
- Introduction
- Receiver
- Transmitter
- Remote Display
- Battery Charger
- Locating
- The Target Steering Function
- Appendix A: System Specifications and Maintenance Requirements
- Appendix B: Projected Depth Versus Actual Depth and the Fore/Aft Offset
- Appendix C: Calculating Depth Based on Distance Between FLP and RLP
- LIMITED WARRANTY
Locating
DigiTrak
®
F2™ Operator’s Manual 61
Interference: What It Is and How to Check for It
Before drilling (preferably before bidding on a project) the interference potential at your site should be
evaluated. Interference can reduce the transmitter’s range or cause variable readings and possibly result
in job slowdowns. Interference comes from two different types of sources: active and passive.
Active interference is also known as electrical interference or background noise and can have varying
effects upon the F2 locating equipment. Most electrical devices emit signals that can affect your ability to
locate the tool accurately or to get good pitch/roll readings. Some examples of active interference are
traffic signal loops, buried dog fences, cathodic protection, radio communications, microwave towers,
cable TV, fiber-trace lines, utility data transmissions, security systems, power lines, and phone lines, to
name a few.
Passive interference can reduce the amount of signal received from the transmitter, which results in
deeper than expected depth readings or a completely blocked signal. Some examples of passive
interference are metal objects (such as pipes, rebar, trench plate, chain-link fence, or vehicles). Two other
examples of passive interference are saltwater/salt domes and conductive earth, such as iron ore.
To install your product accurately and safely, the location of every underground structure proximal to the
intended bore path should be confirmed by potholing. This task is the first step in familiarizing yourself
with the interference potential along your intended bore path. The next step is to conduct an electrical
interference/background noise check.
There are two steps to the interference/background noise check. The first step requires one person, the
second step requires two people.
CAPTION
With the transmitter off, power up the receiver and walk the bore path while monitoring the signal strength
on the receiver’s screen, noting any locations where it changes. A general rule is that the background
noise should be at least 150 points less than the transmitter’s signal strength when measured at the
maximum depth for that bore.