Note 5 - Fair Value Measurements (Details Textual) - USD ($)	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Impairment of Intangible Assets, Finite-lived		$ 11,133
Goodwill, Foreign Currency Translation Gain (Loss)	(140,240)
Goodwill, Impairment Loss	0
Genasys Acquisition [Member]
Goodwill, Impairment Loss		0
Intangible Assets from Genasys Acquisition [Member]
Impairment of Intangible Assets, Finite-lived		0
Fair Value, Nonrecurring [Member]
Impairment of Intangible Assets, Finite-lived	0
Goodwill, Impairment Loss			[1]
Fair Value, Nonrecurring [Member] | Intangible Assets from Genasys Acquisition [Member]
Impairment of Intangible Assets, Finite-lived			[2]
Fair Value, Inputs, Level 3 [Member]
Marketable Securities, Total	$ 0	$ 0

[1] Represents acquired goodwill from the acquisition of Genasys Spain. There was no impairment related to these assets. Refer to Note 8, Goodwill and Intangible Assets, for more information.

[2] Represents acquired intangible assets from the acquisition of Genasys Spain. There was no impairment related to these assets. Refer to Note 8, Goodwill and Intangible Assets, for more information.