Note 6 - Convertible Promissory Note- Schedule of Convertible Debt (Details) - The July 2019 Note [Member] - Convertible Debt [Member] - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022	Jul. 31, 2023	Mar. 31, 2023	Jan. 31, 2023	Jul. 23, 2019
Debt Instrument, Maturity Date	Jan. 31, 2024	Jul. 31, 2023
Stated interest rate	24.00%	24.00%				24.00%
Conversion price (in dollars per share)	$ 1.07	$ 6.30	$ 1.07	$ 2.65	$ 2.87
Face value	$ 397,000	$ 1,000,000				$ 1,000,000
Debt Instrument, Unamortized Discount (Premium), Net	59,000	(38,000)
Carrying value	$ 456,000	$ 962,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The price per share of the conversion feature embedded in the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount, after accumulated amortization, of debt discount (premium).

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