Note 2 - Basis of Presentation and Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Number of Wholly Owned Subsidiaries	8
Number of Additional Inactive Subsidiaries	2
Investments, Typical Final Maturity Maximum (Year)	3 years
Investments, Typical Portfolio Weighted Average Maturity (Month)	18 months
Cash and Cash Equivalents, at Carrying Value, Total	$ 8,665	$ 12,736
Restricted Cash, Total	854	923
Deferred Revenue for Collection Issues	0	0
Accounts Receivable, Allowance for Credit Loss, Ending Balance	66	181
Inventory Obsolescence Write Down (Recoveries)	319	295
Inventory Obsolescence Write Down (Recoveries)	(319)	(295)
Cost of Revenue	24,901	26,759
Advertising Expense	512	677
Standard and Extended Product Warranty Accrual	$ 132	159	$ 146
Number of Reportable Segments	2
Gain (Loss), Foreign Currency Transaction, before Tax	$ 207	704
Shipping and Handling [Member]
Cost of Revenue	$ 392	$ 836
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	2 years
Finite-Lived Intangible Asset, Useful Life (Year)	3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years
Finite-Lived Intangible Asset, Useful Life (Year)	15 years
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Number Of Major Customers	3
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Customer 1 [Member]
Concentration Risk, Percentage	22.00%	43.00%
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Customer 2 [Member]
Concentration Risk, Percentage	10.00%	19.00%
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Customer 3 [Member]
Concentration Risk, Percentage	10.00%

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