CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 383,000	$ 524,000
Receivables, net	2,416,000	2,149,000
Inventories	1,611,000	871,000
Prepaids and other assets	2,001,000	1,551,000
Total current assets	6,411,000	5,095,000
Long-term assets:
Rental equipment, net	364,000	411,000
Property, plant and equipment, net	1,899,000	1,950,000
Right of use assets	1,065,000	1,162,000
Other assets	34,000	33,000
Total long-term assets	3,362,000	3,556,000
TOTAL ASSETS	9,773,000	8,651,000
Current liabilities:
Accounts payable	4,883,000	5,248,000
Accrued liabilities	4,365,000	4,287,000
Current portion of long-term debt	2,940,000	3,030,000
Current lease liabilities	419,000	397,000
Customer deposits	3,079,000	1,951,000
Total current liabilities	15,686,000	14,913,000
Long-term liabilities:
Long-term debt, less current portion	500,000	500,000
Long-term lease liabilities	696,000	805,000
Deferred pension liability and other	3,319,000	3,381,000
Total long-term liabilities	4,515,000	4,686,000
Total liabilities	20,201,000	19,599,000
Stockholders' deficit:
Preferred Stock Series A - $20 stated value - 416,500 shares authorized; shares issued and outstanding: 0 in 2022 and 2021 and Preferred Stock Series B - $200 stated value - 51,000 shares authorized; shares issued and outstanding: 0 in 2022 and 2021
Common Stock - $0.001 par value - 30,000,000 shares authorized; shares issued: 13,474,116 in 2022 and 2021; shares outstanding: 13,446,276 in 2022 and 2021	13,000	13,000
Additional paid-in-capital	41,330,000	41,330,000
Accumulated deficit	(42,482,000)	(42,975,000)
Accumulated other comprehensive loss	(6,226,000)	(6,253,000)
Treasury stock - at cost - 27,840 common shares in 2022 and 2021	(3,063,000)	(3,063,000)
Total stockholders' deficit	(10,428,000)	(10,948,000)
TOTAL LIABILITIES AND STOCKHOLDERS' DEFICIT	9,773,000	8,651,000
Convertible Preferred Stock [Member] | Series A Preferred Stock [Member]
Stockholders' deficit:
Preferred Stock Series A - $20 stated value - 416,500 shares authorized; shares issued and outstanding: 0 in 2022 and 2021 and Preferred Stock Series B - $200 stated value - 51,000 shares authorized; shares issued and outstanding: 0 in 2022 and 2021
Convertible Preferred Stock [Member] | Series B Preferred Stock [Member]
Stockholders' deficit:
Preferred Stock Series A - $20 stated value - 416,500 shares authorized; shares issued and outstanding: 0 in 2022 and 2021 and Preferred Stock Series B - $200 stated value - 51,000 shares authorized; shares issued and outstanding: 0 in 2022 and 2021