Tektronix SPG8000A, User Manual

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40 SPG8000A User Manual
Use Stay Genlock
®
Stay Genlock
®
details
Stay GenLock
®
is a digital genlock technology developed by Tektronix to
provide additional robustness and stability for genlocked Sync Pulse
Generators (SPGs), as in a master/slave configuration.
If the external reference is removed from the genlock input, the instrument
must use the internal oscillator as a frequency reference. Although the OXCO
is a precision component, small frequency differences are inevitable. However,
the Stay GenLock
®
technology maintains a history of the clock frequency, and
therefore attempts to hold the last stable frequency before genlock was lost.
See Video Sync Pulse Generator and Electronic Changeover Unit System
Integration Technical Reference
manual for more information about the Stay
Genlock
®
function.
Enable Stay Genlock
®
To enable the Stay GenLock
®
function on the instrument:
Note : These procedures use the front panel controls on the instrument to enable
Stay GenLock
®
. You can also use the Reference menu in SPG8000A Web
Interface to enable Stay GenLock
®
. (See
Reference menu
.)
1. On the front - panel press REFERENCE to access the REFERENCE
menu.
2. Press the up (▲) or down (▼) arrow button to display REFERENCE :
LOCK LOSS ACTION .
3. Press the left (◄) or right (►) arrow button to display Stay at
Current Frequency , and then press ENTER to confirm the selection.
Use Genlock Lock Action mode
In some cases, locking to a reference can cause a disruption or shock to the
sync signals. To prevent this disruption, Genlock Lock Action mode can be
set so you have to allow the system to lock or relock to the reference. This
mode is supported when locking to NTSC, PAL, tri - level, and CW signals.
T o access Genlock Lock Action mode:
1.
Press
REF
.
2.
Press the up (▲) or down (▼) arrow button to display the
REFERENCE : GL LOCK ACTION MODE
menu.