Note 15 - Business Segments - Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Jun. 30, 2021
Net Revenue	$ 10,922	$ 8,201	$ 21,093	$ 15,042
Operating Income / (loss)	656	(37)	1,626	(364)
Assets	42,552	38,363	42,552	38,363	$ 38,306
Depreciation and amortization	769	766	1,502	1,469
Capital expenditures	357	128	795	217
Manufacturing [Member]
Net Revenue	3,528	3,569	7,090	6,194
Operating Income / (loss)	(48)	81	252	63
Assets	14,799	11,739	14,799	11,739
Depreciation and amortization	104	110	208	212
Capital expenditures	35	87	95	154
Testing Services [Member]
Net Revenue	4,966	3,560	9,566	6,514
Operating Income / (loss)	588	(336)	1,124	(673)
Assets	24,546	21,900	24,546	21,900
Depreciation and amortization	644	636	1,251	1,222
Capital expenditures	322	41	699	63
Distribution [Member]
Net Revenue	2,420	1,065	4,418	2,323
Operating Income / (loss)	277	120	531	244
Assets	1,850	802	1,850	802
Depreciation and amortization	0	0	2	0
Real Estate Segment [Member]
Net Revenue	8	7	19	11
Operating Income / (loss)	(28)	(34)	(51)	(61)
Assets	1,283	3,846	1,283	3,846
Depreciation and amortization	21	20	41	35
Capital expenditures			1
Fabrication [Member]
Operating Income / (loss)	0	0	0	0
Assets	0	0	0	0
Depreciation and amortization	0	0	0	0
Corporate and Unallocated [Member]
Operating Income / (loss)	133	132	(230)	63
Assets	74	76	74	76
Depreciation and amortization	$ 0	$ 0	$ 0	$ 0