Note 8 - Segment Reporting (Details) - Segment Reporting (USD $)	3 Months Ended
Jul. 31, 2013	Jul. 31, 2012	Apr. 30, 2013
Segment Reporting Information [Line Items]
Total revenues	$ 6,774,000	$ 4,257,000
Segment gross margin	2,208,000	1,389,000
Goodwill	1,942,000	1,942,000	1,942,000
Electronic Manufacturing Services [Member]
Segment Reporting Information [Line Items]
Total revenues	4,308,000	2,554,000
Segment gross margin	983,000	610,000
Proprietary Products [Member]
Segment Reporting Information [Line Items]
Total revenues	2,466,000	1,703,000
Segment gross margin	1,225,000	779,000
Goodwill	$ 1,942,000	$ 1,942,000

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

-URI http://asc.fasb.org/extlink&oid=14024403&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

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- Definition

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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