Note 3 - Concentrations of Credit Risk (Details Textual) - USD ($) $ in Millions	3 Months Ended			6 Months Ended		10 Months Ended
	Jul. 31, 2023	Apr. 30, 2022	Jan. 31, 2022	Apr. 30, 2023	Apr. 30, 2022	Jul. 31, 2023
Cash, Uninsured Amount	$ 2.9					$ 2.9
Revenue from Contract with Customer Benchmark [Member] | Customer Concentration Risk [Member] | Wireless Carrier [Member]
Concentration Risk, Percentage	12.00%
Revenue from Contract with Customer Benchmark [Member] | Customer Concentration Risk [Member] | One Distributor [Member]
Concentration Risk, Percentage		16.00%		23.00%		13.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Wireless Carrier [Member]
Concentration Risk, Percentage	12.00%	19.00%			19.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Distributor One [Member]
Concentration Risk, Percentage			4.00%