Interesting device! Quickly reading, it’s apparently a simple circuit for driving an oscilloscope. You’re not going to get a signal suitable for an LCD out of it directly. You could drive a CRT but would probably need to modify one for direct control of the beam.
A “modern” alternative would be to pair it with a digital oscilloscopes like the DSO138, a euro-module like Mordax Data, forthcoming Korg NTS-2, &c., (see above in this topic).