CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Net Sales:
Total net sales	$ 5,121,845	$ 4,835,065	$ 9,991,497	$ 9,346,493
Cost of sales:
Total cost of sales	2,218,854	2,539,894	4,522,683	4,449,675
Gross profit	2,902,991	2,295,171	5,468,814	4,896,818
Operating expenses:
Research and development	689,654	712,019	1,289,952	1,378,634
Selling, general and administrative	1,602,118	1,531,389	3,335,272	3,234,663
Total operating expenses	2,291,772	2,243,408	4,625,224	4,613,297
Operating income	611,219	51,763	843,590	283,521
Interest income	152	65,721	1,031	144,591
Other income	17,371	11,219	33,763	28,499
Income before income taxes	628,742	128,703	878,384	456,611
Income tax expense (benefit)	20,165	(309,402)	29,662	(309,402)
Net income	$ 608,577	$ 438,105	$ 848,722	$ 766,013
Net income per common share:
Basic (in dollars per share)	$ 0.04	$ 0.03	$ 0.05	$ 0.05
Diluted (in dollars per share)	$ 0.04	$ 0.03	$ 0.05	$ 0.04
Weighted average shares outstanding:
Basic (in shares)	17,222,165	16,931,138	17,218,275	16,920,087
Diluted (in shares)	17,223,998	17,123,388	17,220,143	17,102,483
Product
Net Sales:
Total net sales	$ 5,102,670	$ 4,645,682	$ 9,905,505	$ 9,104,376
Cost of sales:
Total cost of sales	2,211,649	2,464,697	4,505,943	4,309,177
Engineering development contracts
Net Sales:
Total net sales	19,175	189,383	85,992	242,117
Cost of sales:
Total cost of sales	$ 7,205	$ 75,197	$ 16,740	$ 140,498