Supplemental Balance Sheet Information (Details) - USD ($)	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Inventories
Work in progress	$ 431,802	$ 545,410
Component parts	7,374,776	7,721,413
Finished goods	2,567,607	2,397,044
Reserve for obsolete and excess inventory	(1,498,915)	(1,472,956)
Inventory, Net	8,875,270	9,190,911
Property, plant and equipment
Total property, plant and equipment at cost	28,117,038	28,680,333
Less accumulated depreciation and amortization	(21,369,468)	(20,859,127)
Total Property, Plant and Equipment, Net	6,747,570	7,821,206
Other accrued liabilities
Accrued compensation expense	1,099,935	1,201,099
Customer deposits	859,307	589,276
Other	381,961	369,191
Other Accrued Liabilities	$ 2,341,203	2,159,566
Maximum [Member]
Property, plant and equipment
Estimated Useful Life	35 years
Minimum [Member]
Property, plant and equipment
Estimated Useful Life	3 years
Machinery and Equipment [Member]
Property, plant and equipment
Total property, plant and equipment at cost	$ 14,399,008	14,693,789
Machinery and Equipment [Member] | Maximum [Member]
Property, plant and equipment
Estimated Useful Life	10 years
Machinery and Equipment [Member] | Minimum [Member]
Property, plant and equipment
Estimated Useful Life	3 years
Building [Member]
Property, plant and equipment
Total property, plant and equipment at cost	$ 13,055,628	13,052,328
Building [Member] | Maximum [Member]
Property, plant and equipment
Estimated Useful Life	35 years
Building [Member] | Minimum [Member]
Property, plant and equipment
Estimated Useful Life	28 years
Land and Land Improvements [Member]
Property, plant and equipment
Total property, plant and equipment at cost	$ 662,402	$ 934,216
Land and Land Improvements [Member] | Maximum [Member]
Property, plant and equipment
Estimated Useful Life	7 years
Land and Land Improvements [Member] | Minimum [Member]
Property, plant and equipment
Estimated Useful Life	5 years