|Sequoia’s LISST-STX is an instrument designed for measuring the settling velocities of suspended sediment in situ. In order to accomplish this, we have fitted a settling column on to a specially designed optics endcap. Electronically, the LISST-STX is similar to the LISST-100X, but the hardware differs significantly from the LISST-100X. The picture below shows the difference between the optics endcaps for the LISST-STX and the LISST-100X instruments.
As the picture shows, the LISST-STX optics endcap is very different from that of the LISST-100X. The LISST-STX optics block must have a large flat surface in order to support the weight of the settling column and motor block, mounted below the optics block. For this reason, it is not possible to use any LISST-100X accessories with the LISST-STX. The only common accessories that are available for the LISST-STX is power and communication cables, instrument stands, and clamps for mounting. A custom mixing chamber, and a custom 50% path reduction module has been developed for the LISST-STX and can be ordered, if necessary. No BioBlock type instrument exist for the LISST-STX.
So, with these caveats in mind, is it possible to use the LISST-STX as a LISST-100X instrument? Certainly! As you can see from the picture, the only difference between the LISST-STX without the settling column and the LISST-100X is the much larger optics block on the LISST-STX. This means that there will be more flow disturbance around the optics end of the LISST-STX than the LISST-100X. There will also be an increased tendency for sediment particles to accumulate inside the optics block, as the optical windows are a bit recessed. Apart from that, the LISST-STX used without the settling column will perform in the same manner as the LISST-100X.