Note 17 - Business Segments - Business Segment Information (Details) - USD ($) $ in Thousands		12 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020
Revenues		$ 44,065	$ 32,462
Operating Income / (loss)		2,353	(61)
Assets		43,421	38,306
Depreciation and amortization		3,075	3,059
Capital expenditures		1,468	1,112
Corporate, Non-Segment [Member]
Operating Income / (loss)		(641)	10
Assets		273	359
Depreciation and amortization		0	0
Manufacturing [Member]
Revenues		13,526	13,151
Manufacturing [Member] | Operating Segments [Member]
Revenues		13,526	13,151
Operating Income / (loss)		275	385
Assets		14,652	13,622
Depreciation and amortization		417	411
Capital expenditures		116	350
Testing Services [Member]
Revenues		19,477	13,846
Testing Services [Member] | Operating Segments [Member]
Revenues		19,477	13,846
Operating Income / (loss)		1,313	(997)
Assets		25,148	21,099
Depreciation and amortization		2,577	2,570
Capital expenditures		1,351	762
Distribution [Member]
Revenues		11,037	5,437
Distribution [Member] | Operating Segments [Member]
Revenues		11,037		$ 5,437
Operating Income / (loss)		1,525	657
Assets		1,740	1,156
Depreciation and amortization		0	4
Capital expenditures		0	0
Real Estate Segment [Member]
Revenues		25	28
Real Estate Segment [Member] | Operating Segments [Member]
Revenues		25	28
Operating Income / (loss)		(119)	(116)
Assets		1,608	2,070
Depreciation and amortization		81	74
Capital expenditures		1	0
Fabrication [Member] | Operating Segments [Member]
Revenues	[1]	0	0
Operating Income / (loss)	[1]	0	0
Assets	[1]	0	0
Depreciation and amortization	[1]	0	0
Capital expenditures	[1]	$ 0	$ 0

[1] Fabrication services is a discontinued operation.