Note 11 - Segment Information - Total Assets by Segment (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Cash and Cash Equivalents	$ 3,691,000	$ 3,863,000
Restricted Cash and Cash Equivalents, Current	100,000	100,000
Accounts receivable, net	1,583,000	1,630,000
Inventories, net	1,360,000	2,444,000
Total assets	7,263,000	8,727,000
Power Supplies [Member]
Accounts receivable, net	1,158,000	1,009,000
Inventories, net	444,000	1,008,000
Other assets	74,000	75,000
Total assets	1,676,000	2,092,000
Property and Equipment
Gross fixed assets	534,000	568,000
Less: accumulated depreciation and amortization	(500,000)	(522,000)
Net power supply fixed assets	34,000	46,000
Data Storage [Member]
Accounts receivable, net	425,000	621,000
Inventories, net	916,000	1,436,000
Other assets	455,000	615,000
Total assets	1,796,000	2,672,000
Property and Equipment
Gross fixed assets	933,000	1,248,000
Less: accumulated depreciation and amortization	(681,000)	(848,000)
Net power supply fixed assets	$ 252,000	$ 400,000