User Manual

VCom Inc.

AP5857 Manual; ml_ap5857_08 (Oct 2005)

Approved: R.B.

5.6.4 Upstream Settings

The Upstream Settings Menu provides access to the settings used to configure the downstream chain. To

access this menu from the Main Menu, type “4” to display the Upstream Settings Menu.

Figure 5.8 Upstream Settings Menu

*** VCom Inc. AP5857 Upstream Settings ***

1)Gain (dB) 46.5

Output Level (dBmV) 23.0 (Stale)

2)Output Mute Auto

3)Output Auto Mute Threshold (dBmV) 30.0

4)Output Alarm Threshold (dBmV) 40.0

5)Output Alarm Threshold Enable Enabled

X)Exit

ENTER)Refresh

Select>_

Upstream Gain

This setting allows the user to set the upstream gain level. Valid

levels are multiples of 0.5 dB. If the gain setting

is within the setting limits but the step size is not correct, the setting will be rounded to the nearest valid step

size boundary.

To change the Upstream Gain, type “1”. The local interface prompt will change to:

Gain [36.0 to 76.0 dB](46.5)> _

Enter the new gain or press ENTER to use the current value.

Upstream Output Level

This level gives an indication of the peak upstream output level. Because upstream signals are time-division

multiplexed, the measured level is only valid while the signal is present. As a result, the peak measured level

of the current signal will be latched and will remain the same until the signal is detected again. Upon detection

of the new signal, the peak level will be measured and a new value returned. If a signal is not detected in 30

seconds, the value returned will remain unchanged, but will be marked “(Stale)” to indicate that a signal has

not been detected in 30 seconds. The range of values returned is 17 dBmV to 50 dBmV.

Upstream Output Mute

This setting allows the user to set the upstream output mute state. There are three valid output states:

Unmuted - force the output to be enabled, Muted – force the output to be disabled, Auto – output is controlled

by system based upon received upstream signal level. Note: output mute setting will be overridden by active

alarm conditions (i.e. output will be muted when an alarm condition is active)

To change the Upstream Output Mute state, type “2”. The local interface prompt will change to:

Output Mute [0 unmute, 1 mute, 2 auto](2)>_

Enter the new value or press ENTER to use the current value.

Upstream Output Auto Mute Threshold

This setting allows the user to set the upstream output auto mute threshold level. When the upstream output

state is set to “Auto” the detection circuitry will unmute the output when a level has been detected above the