14
DHY-03 User Handbook
C
ONFIGUR
A
TION & C
ONTR
OLS
CONFIGURATION & CONTROLS
2
Figure 2-5 : PCB Layout.
DHY-03 Internal Controls & Adjustments
If you need to get inside the unit to make configuration adjustments, simply remove the
4 screws in the corners of the rear panel. The rear panel and main PCB will slide backwards
out of the metal chassis.
When re-inserting the main PCB, ensure that the PCB edges are in the runners inside the
chassis and also that the power LED and line connect button are in the correct place in the
front panel.
Warning : The power must be switched off at the supply or the power lead must be
disconnected before attempting to open the unit. Removal of the cover can expose
dangerous voltages.
Warning : The telephone line plug should be disconnected from the telecommunications
network exchange line before removing the cover.
There are 3 jumpers on the main board:
JP1 is used to switch an extra 10dB of audio input gain to allow for use of domestic level
mixing desks.
JP2 is user selectable, the function being set via parameter 6 in the serial port interface. It is
used mainly for debugging the network cancellation algorithm.
JP3 allows the conferencing port output to be used as a record out by mixing the input and
output signals together and routing them to the Conference Output Phase & Non-Phase pins.
JP1
JP3
JP2