CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Oct. 31, 2012	Oct. 31, 2011
Cash flows from operating activities:
Net income (loss)	$ 1,388	$ (895)
Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities:
Depreciation and amortization	87	66
Warranty reserve expense	73	7
Changes in operating assets and liabilities:
Accounts receivable	(2,189)	(821)
Costs and estimated earnings in excess of billings on uncompleted contracts	726	32
Deferred cost of revenue	(8)	(263)
Inventories	1,124	(1,286)
Other assets	41	(185)
Accounts payable	(907)	812
Billings in excess of costs and estimated earnings on uncompleted contracts	453	(142)
Accrued payroll and related taxes	1	43
Warranty reserves	(131)	(12)
Payable to Parent	0	1
Other liabilities	(29)	(17)
Deferred revenues	(36)	1,380
Net cash provided by (used in) operating activities	593	(1,280)
Cash flows from investing activities:
Purchases of certificates of deposit	0	(500)
Proceeds from redemption of certificates of deposit	250	499
Additions to equipment, furniture and fixtures	(175)	(64)
Net cash provided by (used in) investing activities	75	(65)
Net increase (decrease) in cash and cash equivalents	668	(1,345)
Cash and cash equivalents at beginning of period	2,783	3,881
Cash and cash equivalents at end of period	3,451	2,536
Supplemental cash flow information:
Cash paid for income taxes	$ 37	$ 0