5
Configuration & Controls - DHY-04, DHY-04S, DHY-04T 2
Gain Switches (Level To & From The Line)
These switches allow gain/attenuation to be applied to the incoming &
outgoing analogue audio. Each switch has 3 positions. Rotating the switches
clockwise give gains of -6dB, 0dB & +6dB. The normal position for the
transmit gain to the telephone line (lower switch) is 0db and for the receive
gain from telephone line (upper switch) is –6dB.
LED Bargraphs
These 8 position bargraphs, by default, indicate the signal levels of the
incoming XLR audio signal from the mixer (lower) and outgoing XLR audio
to the mixer (upper). For best operation set the signal gain switches to
achieve all 3 yellow LEDs mostly illuminated with occasional audio peaks
lighting the first red LED.
The scale indicates from left to right: Green (-30dB, -18dB, -6dB); Yellow
(-3dB, 0dB, +3dB); & Red (+6dB, +9db).
Status & Operating Mode Information
The LED display is also used to indicate special operating modes and other
settings as follows:
• Alternating 2 LEDs on, 2 LEDs off pattern indicates that the DHY-04 is
checking the status of the Line Connect Button to test the Bootstrap
Mode (see page 36)
• Alternating 4 LEDs on, 4 LEDs off pattern indicates that the DHY-04 has
entered Bootstrap mode, because either the Line Hold/Connect Button
was held down for approximately 10 seconds at power up, or the main
code has been corrupted (most likely due to a previous incomplete
firmware update).
• Alternating 8 LEDs on, 8 LEDs off pattern indicates that the DHY-04 has
received an update command from the web page and is updating the
firmware (valid in either Bootstrap or Normal operation).
• On normal power up, the top row of LEDs shows the current country
selection (see table 2-1) with LEDs numbered from left to right reflecting
the DIPSwitch settings.
DHY-04 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.
Jumper and Select Switcher Functions
Put a 2 pin jumper over J1 to switch in an extra 10dB of audio input gain to
allow for use of domestic level mixing desks.
Figure 2-2: Internal Position of Jumper J1.