CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 29, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 5,154	$ 5,276
Restricted cash	405	312
Accounts receivable, net	5,504	3,794
Current portion of lease receivable	255	247
Contract revenue in excess of billings	4,657	2,763
Inventories, net	4,258	3,973
Prepaid expenses and deposits	688	712
Total current assets	20,921	17,077
Long-term lease receivable, net of current portion	707	836
Property and equipment, net	4,447	4,527
Goodwill	635	635
Other assets	2,039	1,955
Total assets	28,749	25,030
Current liabilities:
Accounts payable	1,900	1,667
Accrued liabilities	1,318	912
Billings in excess of contract revenue	9,229	7,117
Current portion of retirement obligations	469	500
Current portion of pension settlement obligation	409	409
Current portion of long-term debt	231	224
Total current liabilities	13,556	10,829
Retirement obligations, net of current portion	4,059	4,150
Pension settlement obligation, net of current portion	4,478	4,478
Long-term debt, net of current portion	1,423	1,540
Deferred rent obligation	591	808
Total liabilities	24,107	21,805
Stockholders' equity:
Preferred stock, no par value: 10,000,000 shares authorized; no shares outstanding	0	0
Common stock, $0.20 par value: 30,000,000 shares authorized; 11,616,866 shares issued	2,323	2,323
Additional paid-in-capital	53,894	53,818
Common stock in treasury, at cost, 264,350 shares	(3,532)	(3,532)
Accumulated deficit	(45,867)	(47,208)
Accumulated other comprehensive loss	(2,176)	(2,176)
Total stockholders' equity	4,642	3,225
Total liabilities and stockholders' equity	$ 28,749	$ 25,030