In attempts to characterize the Jamming Avoidance Response, I ran various tests on the fish.
I wanted to make sure that in the absence of other fish or artificial stimuli that the fish in testing would stay at a constant frequency. To do this, I simply recorded the frequency of the fish over a period of 30 minutes. After the recording, I checked the frequency at regular intervals and confirmed that the fish maintains a steady frequency over time.
As per the Watanabe and Takeda paper, the Eigenmannia species can be "chased" to the outer limits of their frequency ranges. This is done by slowly following the direction of the fish's frequency changes with the stimulus frequency. This ensures that the stimulus frequency is always close enough to elicit the JAR behavior.
I attempted a similar experiment with the Apteronotus Albifrons (Black Ghost Knife Fish). So far, I've only been able to chase the frequency downwards.
Long Term Frequency Elevation:
Other research on the weakly electric fish indicates that a stimulus frequency that persists can cause the effects of the JAR to persist as well. I simply left the function generator on at a set frequency for 2 hours and observed the results. I was able to modulate the frequency of the Black Ghost Knife Fish by over 40 Hz.