ACCRUED LIABILITIES (Details) - USD ($)	Apr. 30, 2016	Apr. 30, 2015
Employee related expenses:
Accrued payroll	$ 236,000	$ 259,000
Accrued payroll taxes	19,000	27,000
Accrued employee benefits	115,000	68,000
Total employee related expenses	370,000	354,000
Other, including interest:
Warranty reserve	67,000	115,000
Property taxes	31,000	28,000
Other		82,000
Total other	98,000	225,000
Total accrued liabilities	$ 468,000	$ 579,000