D105 Receiving Tone

Built into the D105 are two receiving functions, one for Audio, and another for sensing DSL frequencies. The DAP125, Differentially Amplified Probe, is connected to the Test Port of the D105. Select CKT-ID to scan various DSL frequencies to determine T1, HDSL, or VDSL presence.

By selecting SPL FUNC and F3 the user can probe and listen for 577/987 tone, or Snoop DSL signals when the probe tip is placed between the Tip and Ring.

The DAP125 probe placed next to the Tip or Ring will receive and display the tone level. The image to the left shows the 577Hz filter is being used. The SET SQL button can be set so only signal levels above the set point can be heard in the speaker.

Since a D105 or TriTone unit can send both Simplex and TriPlex, they are an ideal choice for a tone sender. When TriPlex is being received the Tip and Ring can be positively identified by placing the probe between the pair.

DSL Snoop mode decodes the selected signal and provides an audible output and level indication. Gain and volume can be adjusted by pressing F2.

SPL FUNC button is used to toggle between HDSL, T1, and VDSL monitoring.