CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	3 Months Ended
	Jul. 31, 2020	Jul. 31, 2019
CONSOLIDATED STATEMENTS OF OPERATIONS
Net sales	$ 6,019,000	$ 6,346,000
Cost of goods sold	3,680,000	3,953,000
Gross profit	2,339,000	2,393,000
Operating expenses:
Engineering	351,000	388,000
Selling, general and administrative	1,363,000	1,423,000
Operating expenses	1,714,000	1,811,000
Income from operations	625,000	582,000
Other expense:
Interest expense, net	23,000	27,000
Income before income tax expense (benefit)	602,000	555,000
Income tax expense (benefit)	(128,000)	111,000
Net income	$ 730,000	$ 444,000
Basic earnings per share	$ 0.12	$ 0.07