Tektronix TekRanger 2 TFS3031, Service Manual

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Performance Check – TekRanger 2 (serial nos. B052000 and above)
4–4
TFS3031 TekRanger/TekRanger 2 Service Manual
1.5 dB
Event dead zone
Although it would be nice to verify the event-detection specification by
physically moving two reflective events closer together until there is only a
1.5-dB dip between events, this is difficult to do. An alternate method is to
measure the displayed pulse width from a reflection, 1.5 dB below the peak. This
alternate measurement works well when the rise and fall time of the outgoing
laser pulse is much faster than the rise and fall time of the pulse measuring
system. If the pulse measuring system is faster than the outgoing laser pulse,
then the alternate method should measure the displayed pulse width from a
reflection 3 dB below the peak instead of 1.5 dB.