RIDGID SeekTech ST-305 - Manual (Page 8)

Ridge Tool Company 
Tools For The Professional TM
SeekTech ® ST-305
Useful Operating Tips
• The lower the resistance, the more current will be put on
the line.
• Scrape away dirt, paint, and corrosion before connecting
to the target conductor or to the grounding spike.
• Insert the grounding spike as far as possible. Eventually
try wetting the area if necessary.
• Keep the transmitter leads short by stowing the excess
length on the transmitter’s body. This will reduce the
amount of interfering signals from the leads. Where
possible, place the transmitter away from the area of the
intended locate. This is especially true in Inductive Mode,
to avoid coupling through the air with the receiver.
• Start by using the lowest frequency and the least amount
of current needed to effectively illuminate the line. Lower
frequencies travel farther because they do not dissipate
as quickly. Higher frequencies generally make it easier to
illuminate a line, but they don’t travel as far and are much
more likely to couple onto other utility lines, distorting
the signal and reducing the accuracy.
Dual-Frequency Transmission
The ST-305 can be placed in Dual-Frequency mode by
pressing the Frequency Key for over 1 second (long press). To
exit Dual-Frequency mode, simply repeat the long press on
the Frequency Key. See Figure 2.
When in Dual Frequency mode the Frequency Key will cycle
with short presses through the following frequency settings:
1. 93 kHz only (rapid flashing 33kHz LED).
2. 33 kHz and 1 kHz dual-frequency transmission
(LEDs for 33 kHz and 1 kHz both lit).
3. 33 kHz and 8 kHz dual-frequency transmission
(LEDs for 33 kHz and 8 kHz both lit).
Dual-Frequency transmission is available only in direct
connect mode.
The advantage of dual frequency is that you combine the
advantage of a lower frequency (less risk to bleed over,
longer distance) with the advantage of the higher frequency
(a higher frequency can “jump” over small hurdles allowing
to continu the trace). Thus you start locating at a lower
frequency and when the signal stops due to eg a rusted valve,
you can switch to a higher frequency without the need to go
back to your transmitter and set the frequency at a higher
frequency.
Inductive Clamp Method
Figure 8: ST-305 with Inductive Clamp
When using an inductive clamp, plug the inductive clamp
jack into the receptacle provided at the end of the transmitter.
The Inductive Mode LED will flash rapidly when a clamp
is connected. Clips and leads are not used. Note that for a
clear signal using an inductive clamp, both ends of the utility
should be grounded.
Clamp the inductive clamp around an accessible portion of
the line chosen to trace. The clamp will induce a signal into
the conductor when the transmitter is powered on.
Select frequency and power as with the Direct Connect
Method. Operational frequency choices for use with an
Inductive Clamp are 1 kHz, 8 kHz, and 33 kHz.
Figure 9: Inductive Clamp Attached to a Conductor