Condensed Consolidated Statements of Cash Flows (unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024
Cash flows from operating activities:
Net income (loss)	$ 6,042	$ (555,863)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation	621,765	645,423
Non-cash lease expense	25,325	0
Gain on disposal of assets, net	(329,520)	(36,886)
Deferred income taxes	0	(165,718)
Changes in operating assets and liabilities:
Accounts receivable, net	(1,745,945)	(1,117,070)
Contract assets	28,904	118,301
Inventories, net	55,960	389,959
Other current assets	(27,966)	442,034
Accounts payable	(386,017)	113,238
Accrued wages and salaries	103,456	56,683
Other accrued liabilities	(28,195)	(63,871)
Unearned revenue and customer deposits	(86,119)	(104,448)
Other long-term liabilities	(220,049)	243,000
Net cash used in operating activities	(1,982,359)	(35,218)
Cash flows from investing activities:
Capital expenditures	(93,703)	(398,663)
Proceeds from the sale of assets	677,905	96,350
Proceeds from short-term investments	247,276	2,508,597
Purchases of short-term investments	0	(1,479,275)
Net cash provided by investing activities	831,478	727,009
Cash flows from financing activities:
Proceeds from debt	500,000	0
Cash dividends paid	(57,968)	(193,226)
Net cash provided by (used in) financing activities	442,032	(193,226)
Net (decrease) increase in cash and cash equivalents	(708,849)	498,565
Cash and cash equivalents at beginning of period	1,922,679	1,387,075
Cash and cash equivalents at end of period	1,213,830	1,885,640
Supplemental disclosure of cash flows information:
Cash paid for income taxes, net of refunds received	21,855	0
Cash paid for interest	7,201	0
Non-cash investing and financing activities:
Operating lease right-of-use asset obtained in exchange for operating lease liability	$ 435,149	$ 0