Note 12 - Segment and Related Information (Detail) - Revenue information by industry segment: (USD $)	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Net Sales
Net Sales	$ 4,761,289	$ 5,068,613	$ 5,259,012
Income (Loss) Before Provision for Income Taxes
Income (Loss) Before Provision for Income Taxes	(783,966)	(672,535)	(949,496)
Indicators and Gauges [Member]
Net Sales
Net Sales	1,612,943	1,253,975	1,357,114
Income (Loss) Before Provision for Income Taxes
Income (Loss) Before Provision for Income Taxes	271,343	94,178	34,647
Automotive Diagnostic Tools and Equipment [Member]
Net Sales
Net Sales	3,148,346	3,814,638	3,901,898
Income (Loss) Before Provision for Income Taxes
Income (Loss) Before Provision for Income Taxes	(78,433)	229,355	188,037
General Corporate Expenses [Member]
Income (Loss) Before Provision for Income Taxes
Income (Loss) Before Provision for Income Taxes	$ (976,876)	$ (996,068)	$ (1,172,180)