Note 18 - Business Segments - Business Segment Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Revenues	$ 43,250	$ 44,065
Operating Income / (loss)	2,228	2,353
Assets	42,186	43,421
Depreciation and amortization	5,088	3,075
Capital expenditures	4,498	1,468
Corporate, Non-Segment [Member]
Revenues	0	0
Operating Income / (loss)	(80)	(641)
Assets	500	273
Depreciation and amortization	0	0
Capital expenditures	26	0
Manufacturing [Member]
Revenues	13,827	13,526
Manufacturing [Member] | Operating Segments [Member]
Revenues	13,827	13,526
Operating Income / (loss)	(58)	275
Assets	13,864	14,652
Depreciation and amortization	481	417
Capital expenditures	143	116
Testing Services [Member]
Revenues	23,130	19,477
Testing Services [Member] | Operating Segments [Member]
Revenues	23,130	19,477
Operating Income / (loss)	1,648	1,313
Assets	24,559	25,148
Depreciation and amortization	4,532	2,577
Capital expenditures	4,329	1,351
Distribution [Member]
Revenues	6,270	11,037
Distribution [Member] | Operating Segments [Member]
Revenues	6,270	11,037
Operating Income / (loss)	816	1,525
Assets	1,275	1,740
Depreciation and amortization	0	0
Capital expenditures	0	0
Real Estate Segment [Member]
Revenues	23	25
Real Estate Segment [Member] | Operating Segments [Member]
Revenues	23	25
Operating Income / (loss)	(98)	(119)
Assets	1,988	1,608
Depreciation and amortization	75	81
Capital expenditures	$ 0	$ 1