Note 6 - Goodwill, Intangible Assets and Long Term Assets - Goodwill Activity by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Apr. 02, 2017	Mar. 27, 2016	Dec. 31, 2016
Balance	$ 19,965	$ 16,283	$ 20,584
Acquisition of Accutronics		4,407	80
Effect of foreign currency translation	83	(106)	(699)
Balance	20,048	20,584	19,965
Battery & Energy Products Segment [Member]
Balance	8,472	4,790	9,091
Acquisition of Accutronics		4,407	80
Effect of foreign currency translation	83	(106)	(699)
Balance	8,555	9,091	8,472
Communications Systems Segment [Member]
Balance	11,493	11,493	11,493
Acquisition of Accutronics
Effect of foreign currency translation
Balance	$ 11,493	$ 11,493	$ 11,493

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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