On the TDS5000 series scopes+ it is possible to get a trigger output corresponding to the start of a selected video line?

On the TDS5000 series scopes+ it is possible to get a trigger output corresponding to the start of a selected video line?

Yes. Click on UTILITIES, select EXTERNAL SIGNALS, and then select B TRIG in the AUX OUT configuration. The trigger will be on the AUX out on the rear panel.