You can get some quantitative data of plant spike characteristics by using time interval measurements and the RMS of the signal. You can hold the rightclick button (press two fingers on the trackpad on Mac OSX) and drag the mouse cursor to select the interval of the signal. When you select the interval of the signal Spike Recorder will display the length of the interval in seconds. In that way, you can measure some characteristic time measurements of spikes like rising time, decaying time, etc.
Please take a look at section "Signal Measurements" in our manual:
https://backyardbrains.com/products/files/SpikeRecorderDocumentation.2018.02.pdf
As you already know, the Spike Recorder can not measure amplitude in mV. But the signal is measured in units linearly proportional to mV so if you are not interested in absolute measurements in mV but just relative measurements that you will use to compare the amplitude of spikes between experiments you can use RMS measurement in Spike Recorder.
If you select just a very short interval of a signal, at the position of the peak of the spike, Spike Recorder will display the RMS value of the signal at that point which you can use as a spike amplitude measure.
Please take a look at the image in the attachment where we got the amplitude of the spike as 15.553 (RMS is displayed in the bottom right corner).
**The way the Plant SpikerBox works is that it doesn't send Action Potentials from one plant to another 1:1, it uses the action potential of one plant - in our case the Venus Flytrap - to trigger a relay which sends a much larger electrical stimulation to the second plant.