CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2013	Apr. 30, 2012
Current assets:
Cash and cash equivalents	$ 6,550	$ 2,783
Certificates of deposit	0	250
Accounts receivable, net of allowance for doubtful accounts of $75	905	789
Costs and estimated earnings in excess of billings on uncompleted contracts	60	726
Deferred cost of revenue	3	6
Inventories	1,570	2,659
Other current assets	448	238
Total current assets	9,536	7,451
Equipment, furniture and fixtures, net	566	482
Other noncurrent assets	54	49
Total assets	10,156	7,982
Current liabilities:
Accounts payable	225	1,070
Accrued payroll and related taxes	482	388
Warranty reserves	107	169
Payable to Parent	252	252
Other current liabilities	42	63
Deferred revenues	2,408	687
Total current liabilities	3,516	2,629
Long-term liabilities	0	12
Total liabilities	3,516	2,641
Commitments and contingencies
Shareholders' equity:
Preferred shares, no par value; 20,000 shares authorized; no shares issued or outstanding	0	0
Common shares, no par value; 50,000 shares authorized; 12,963 shares issued and outstanding	56,370	56,370
Accumulated deficit	(49,730)	(51,029)
Total shareholders' equity	6,640	5,341
Total liabilities and shareholders' equity	$ 10,156	$ 7,982