Verify the trigger!

You may encounter a situation where shortly after focusing and/or grabbing Scanbox quits and asks you to “verify the trigger”.  If this happens proceed as follows:

First, if  you hear the resonant mirror starting to work (meaning you hear the 8khz tone) when you press focus or grab, skip to the next step below.  Otherwise, make sure the connection from the resonant mirror to the controller is well seated. Also check the connectors to the resonant controller inside the Scanbox.  The resonant controller is the small square board that is mounted on top of the large Scanbox card.  Try scanning again.  If you still don’t hear the resonant mirror working, let us know.

Untitled 6.001

Second, assuming the resonant mirror works, there are two connections that you need to check that may cause this message to appear (see diagram above.)

The first connection runs form the laser SYNC OUT to the Alazartech External Clock input (via a microcircuits filter).  Verify by means of an oscilloscope that, when the laser is mode-locked, you see a clean sinusoidal signal at the input to the external clock with a peak-to-peak amplitude > 1.5V and a frequency equal to that of the laser (typically ~80MHz).

If you are using a Spectra Physics laser, you probably have a video amplifier in-between the output of the laser and the input to the Alazartech card.  Make sure the amplifier is powered and verify the amplitude of the signal. If the signal looks good then proceed to step #3.  Otherwise, let us know.

The second signal that must be checked originates from the Scanbox TRIG OUT SMA connector and must be connected to the external trigger (TRIG IN) input of the Alazartech card. Make the connectors are sitting properly and the cable is Ok.

If, after going through the above procedure, you still can’t get the microscope to trigger please contact us.

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