Condensed Consolidated Statements of Cash Flows - USD ($)	6 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating activities:
Net (loss) income	$ (526,762)	$ 8,803,532
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
(Recovery of) Provision for credit losses	(4,105)	8,473
Depreciation of equipment and leasehold improvements	93,647	135,915
Accretion of discount on treasury securities	(234,298)	(16,232)
Noncash operating lease expense	3,835	4,476
Stock-based compensation expense	84,040	166,708
Change in cash surrender value of life insurance	(152,892)	(143,691)
Provision (benefit) for deferred compensation	63,255	(46,075)
Net changes in operating assets and liabilities:
Accounts receivable	(130,286)	558,058
Inventories	1,256,774	801,766
Prepaid expenses and other current assets	(59,750)	(164,503)
Interest receivable	(82,896)	(128,030)
Income taxes receivable	(40,462)
Income taxes payable	(83,479)	494,839
Accounts payable	(5,011)	(510,681)
Accrued liabilities	(418,796)	732,493
Deferred revenue	(107,999)	(158,464)
Net cash (used in) provided by operating activities	(345,185)	10,538,583
Investing activities:
Purchase of equipment and leasehold improvements	(401,594)	(50,492)
Life insurance premiums paid	(81,744)	(87,995)
Proceeds from the maturity of treasury securities	7,223,000
Purchases of treasury securities	(6,997,085)	(14,884,929)
Net cash used in investing activities	(257,423)	(15,023,416)
Financing activities:
Proceeds from exercise of stock options	35,800	88,940
Net cash provided by financing activities	35,800	88,940
Net (decrease) in cash and cash equivalents	(566,808)	(4,395,893)
Cash and cash equivalents at beginning of period	3,091,062	9,208,170
Cash and cash equivalents at end of period	2,524,254	$ 4,812,277
Supplemental cash flow information:
Cash paid for income taxes	$ 127,700