Note 1 - Operations and Summary of Significant Accounting Policies (Details Textual)	3 Months Ended		12 Months Ended
	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)	Jan. 17, 2025 USD ($)
Restricted Cash and Cash Equivalent, Current	$ 150,000		$ 150,000
Accounts Receivable, Allowance for Credit Loss, Current	$ 12,000		15,000
Product Warranty Obligation, Term (Month)	27 months
Standard Product Warranty Accrual	$ 337,000		333,000
Inventory Valuation Reserves	752,000		758,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	0		0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0		$ 0
Unrecognized Tax Benefits	0	$ 0
Proceeds from Income Tax Refunds	0
Interest Paid, Excluding Capitalized Interest, Operating Activity	57,000	$ 45,000
Impairment, Long-Lived Asset, Held-for-Use	$ 0
IT Equipment Loan [Member]
Debt Instrument, Face Amount				$ 192,000
Domestic Tax Jurisdiction [Member]
Open Tax Year			2021 2022 2023 2024
State and Local Jurisdiction [Member]
Open Tax Year			2020 2021 2022 2023 2024
Minimum [Member]
Number Of Years Supply Certain Larger Quantities Of Other Product Support Items May Have To Be Purchased	1