Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
CASH FLOWS FROM OPERATING ACTIVITIES
Net earnings	$ 2,817	$ 577
Adjustments to reconcile net earnings to net cash provided by (used in) operating activities:
Depreciation and amortization	1,176	1,279
Provision for excess and obsolete inventory	135	123
Foreign exchange (gain) loss	(18)	40
Amortization of deferred compensation related to stock-based awards	474	372
Discount on shares sold under Employee Stock Purchase Plan	(8)	(8)
Proceeds from sale of demonstration equipment, net of gain	6	19
Deferred income tax benefit	(404)	(438)
Changes in assets and liabilities:
Trade accounts receivable	291	(832)
Inventories	(2,038)	(2,177)
Prepaid expenses and other current assets	(740)	(374)
Other assets	2	(8)
Operating lease liabilities	(423)	(346)
Accounts payable	403	1,592
Accrued wages and benefits	(654)	(1,179)
Accrued professional fees	(142)	(520)
Customer deposits and deferred revenue	921	(608)
Accrued sales commissions	(221)	(20)
Domestic and foreign income taxes payable	864	(395)
Other current liabilities	43	40
Other liabilities	(16)	60
Net cash provided by (used in) operating activities	2,484	(2,787)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of property and equipment	(334)	(335)
Net cash used in investing activities	(334)	(335)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from shares sold under Employee Stock Purchase Plan	40	48
Proceeds from stock options exercised	165	0
Acquisition of treasury stock – shares surrendered by employees to satisfy tax liability	(33)	0
Net cash used in financing activities	(853)	(835)
Effects of exchange rates on cash	71	(27)
Net cash provided by (used in) all activities	1,368	(3,984)
Cash, cash equivalents and restricted cash at beginning of period	14,576	21,195
Cash, cash equivalents and restricted cash at end of period	15,944	17,211
Cash payments for:
Domestic and foreign income taxes	118	966
Term Note [Member]
CASH FLOWS FROM FINANCING ACTIVITIES
Repayments of Term Note	$ (1,025)	$ (883)