Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash, Uninsured Amount	$ 2,700	$ 2,300
Depreciation, Total	5,300	5,200
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset	$ 0
Standard Warranty Extended Term for Exceptions (Year)	10 years
Defined Contribution Plan, Cost	$ 2,900	1,400
Research and Development Expense, Total	$ 3,600	$ 3,700
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares (in shares)	1,375,000	1,029,000
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax, Ending Balance		$ (100)
Other Expense [Member]
Foreign Currency Transaction Gain (Loss), before Tax, Total	$ 100	$ 200
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	20 years
Standard Warranty Term (Year)	5 years
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	5 years
Standard Warranty Term (Year)	1 year
Leasehold Improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	15 years