Note 6 - Inventories, net (Tables)

6 Months Ended

Sep. 30, 2018

Inventory Disclosure [Abstract]

Schedule of Inventory, Current [Table Text Block]

Inventories consist of:

	September 30, 2018			March 31, 2018
Purchased parts	$	2,956,459		$	3,571,874
Work-in-process		1,254,607			1,051,725
Finished goods		16,098			66,335
Less: Inventory reserve		(465,000	)		(420,000	)
	$	3,762,164		$	4,269,934