Note 4 - Inventory - Schedule of Inventory (Details) - USD ($) $ in Thousands	Apr. 30, 2024	Apr. 30, 2023
Parts and raw material	$ 6,111	$ 5,704
Work in process	3,349	3,194
Finished goods	62	49
Total Inventory, net of allowance	$ 9,522	$ 8,947

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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