Nokia 7000 Series Network Router User Manual


 
Chapter 8: VPD-6830 Programmable Video DA Series VPD-6830-DLY240
88 6800/7000 Series - Distribution and Routing Products Installation and Operation Manual
VPD-6830-DLY240
Configuration
The VPD-6830-DLY240 provides adjustable delay from 0 to 240 ns. The
additional delay submodule is shown on the VEA-6840 base card in
Figure 8-15 on page 91.
To configure the VPD-6830-DLY240:
1. Set the Input Coupling for either AC or DC coupling using jumpers
J1 and J2. See Figure 8-15 on page 91 for jumper locations.
2. Set the clamping mode on jumper J3 to either Soft, Hard, or No
Clamp. See Figure 8-15 on page 91 for jumper location.
3. Adjust the gain over a range of -3 dB to +3 dB using the R5
multi-turn potentiometer in the base module.
Turn the potentiometer clockwise to increase the gain. See
Figure 8-16 on page 92.
4. Adjust the equalization using the R6 multi-turn potentiometer in the
base module.
Turn the potentiometer clockwise to obtain more equalization. See
Figure 8-16 on page 92.
5. Make fine adjustments to the high-frequency response using the R21
single-turn potentiometer in the base module.
The high-frequency response is factory-set/calibrated.
Readjustment is not recommended without precise test equipment.
See Figure 8-16 on page 92.
6. Position the delay submodule P2 jumpers horizontally across the
jumper sockets, connecting pins 2 & 4, and pins 1 & 3.
Connecting the jumpers horizontally puts them in Bypass mode.
Connecting them vertically puts them in Use mode. See Figure 8-15
on page 91 for an illustration of this jumper set.
7. Position the delay submodule P3 jumpers either horizontally
(Bypass mode) or vertically (Use mode) across the jumper sockets.
Jumper P3 is a six-section, two-position jumper set. This jumper
“selects” the desired amount of selectable delay. For each section,
there are two jumper positions: horizontal and vertical. The
horizontal position is Bypass mode, where a designated amount of
delay can be bypassed. The vertical position is the Use position,