Ross VEA-8707A, Руководство пользователя

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VEA-8707A User Manual (Iss. 01) User Controls • 3–3
• 8281 — Select this option when using Belden 8281 cables. This is the default.
• 1694 — Select this option when using Belden 1694A cables.
• 1505 — Select this option when using Belden 1505A cables.
7. Clamping Speed Selection (JP3)
If
JP4
is set to the ON position, set
JP3
to configure the clamping speed as follows:
• NORM — Select this option for normal back porch clamping and to set the DC level of
the back porch to ground level. This is the default.
• FAST — Select this option for fast back porch clamping. Use this setting for any signals
which require clamping in less than 17 lines. This mode may be useful if the input signal
is hard switched between two video signals with different DC offsets.
8. Back Porch Clamping (JP4)
Use
JP4
to configure the Back Porch Clamping feature as follows:
• ON — Select this option to enable the Back Porch Clamping feature on the supported
formats. This is the default.
• OFF — Select this option to disable the feature or when using a format not supported for
clamping (refer to Table 5.1 ). You must use this setting for any signals that do not include
sync pulses such as AES audio, component, and unsupported Tri-Level Sync signals.
9. Input Coupling (JP1 and JP2)
Use
JP1
and
JP2
in conjunction to set the input coupling. The two jumpers must both be
positioned on their AC or DC pin settings.
• AC — Use this setting if the back porch of the input signal is displaced from ground level
by more than ±0.5V DC.
• DC — Use this setting to configure the entire amplifier to be DC coupled. This is the
default.
10. Local Termination Jumper (JP8)
Use
JP8
to configure an optional 75ohm termination on the input of the VEA-8707A as follows:
• TERM — Select this option to terminate the input signal on the card. This is the default.
• LOOP — Select this option to leave the input unterminated. For example, use this setting
if you wish to loop the signal to another device.
For More Information...
• when setting the clamping speed, refer to the section “ Notes on Clamping ” on page 3-6.
• on the supported formats for clamping, refer to Table 5.1 .