Tektronix TG700, Руководство пользователя

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HD3G7 HD 3 Gb/s SDI Video Generator
The HD3G7 generator module’s adjustable zone plate signal provides a better way:
The H Sweep Zoneplate pattern control parameter is the H Sweep Frequency,
which controls the upper frequency limit of the sweep (the swept-to
frequency).
Simply adjust the H Sweep Frequency until the system roll-off is at –3 dB.
Read the frequency directly from the TG700 display.
The H Sine Zoneplate, which provides a constant frequency horizontal sine
signal instead of a swept signal, can be used to reduce error in measuring
attenuation at a given frequency.
Set the Horz. Frequency parameter to a low value and measure the
amplitude of the entire line.
Next, calculate the –3 dB point (0.707 × the low frequency amplitude).
Finally, increase the Horz. Frequency parameter until the system response
for the whole line is at the calculated –3 dB level, and read the –3 dB
frequency directly from the TG700 display.
Since the ZP Amplitude parameter is adjustable for each of these signals, you
can measure the response at 100%, 60%, or any other level as needed.
These same techniques can be used to measure vertical or diagonal response, by
selecting the appropriate zoneplate signal.
HD3G7 Module Main Menu
Use the HD3G7 module main menu to perform the following tasks:
Set the video signal output mode.
Scroll the active picture area of the output signal.
Change the sample structure and color space.
Control the Embedded Audio characteristics: frequency, amplitude, click
rate, and sampling rate.
Set the timing offset of the outputs relative to an internal reference signal or
an external reference signal.
Enable or disable the Timecode and set the timecode parameters.
Enable or disable the discrete components of the video output signal.
Enable or disable the user-de fi ned Ancillary Payload and set the payload
structure.
Enable or disable the SMPTE352 Payload identi fi er.
TG700 TV Signal Generator Platform User Manual 3–161