CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2013	Apr. 30, 2012
Cash flows from operating activities:
Net income	$ 3,099	$ 1,233
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	181	141
Inventory obsolescence reserve	0	334
Deferred income taxes	(1,555)	0
Warranty reserve expense	153	159
Impairment charge for patent write-off	0	16
Changes in operating assets and liabilities:
Accounts receivable	(1,265)	(586)
Costs and estimated earnings in excess of billings on uncompleted contracts	726	(694)
Deferred cost of revenues	(126)	107
Inventories	(1,137)	(2,557)
Other current assets	(64)	(106)
Accounts payable	1,110	918
Billings in excess of costs and estimated earnings on uncompleted contracts	0	(231)
Accrued payroll and related taxes	(4)	62
Warranty reserves	(183)	(21)
Payable to Parent	(50)	1
Other liabilities	(37)	(4)
Deferred revenues	4,764	72
Net cash provided by (used in) operating activities	5,612	(1,156)
Cash flows from investing activities:
Purchases of certificates of deposit	(1,245)	(500)
Proceeds from redemption of certificates of deposit	250	749
Additions to equipment, furniture and fixtures	(141)	(191)
Net cash (used in) provided by investing activities	(1,136)	58
Net increase (decrease) in cash and cash equivalents	4,476	(1,098)
Cash and cash equivalents at beginning of year	2,783	3,881
Cash and cash equivalents at end of year	7,259	2,783
Supplemental cash flow information:
Cash paid for income taxes	48	0
Non-cash inventory activities:
Inventory transferred to equipment	$ 131	$ 0