SEGMENT REPORTING (Details) (USD $)	12 Months Ended
	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2011
Revenue	$ 42,328,675	$ 65,462,157
Depreciation and amortization	1,332,169	1,775,672
Income (loss) before income taxes from continuing operations	(7,224,144)	(14,814,781)
Goodwill	0	1,930,826	2,044,856
Total assets	18,144,966	35,795,399
Additions of property and equipment	1,076,225	416,531
Corporate Segment [Member]
Revenue	0	0
Depreciation and amortization	30,964	64,651
Income (loss) before income taxes from continuing operations	(7,585,648)	(3,648,421)
Goodwill		0
Total assets	2,679,196	8,907,729
Additions of property and equipment	0	11,781
Wireless Communication [Member]
Revenue	17,664,517	23,311,966
Depreciation and amortization	346,410	503,196
Income (loss) before income taxes from continuing operations	(2,093,262)	(163,226)
Goodwill		1,930,826
Total assets	4,910,535	8,936,442
Additions of property and equipment	163,087	160,735
Specialty Construction [Member]
Revenue	5,257,932	6,093,745
Depreciation and amortization	721,893	766,857
Income (loss) before income taxes from continuing operations	412,297	313,419
Goodwill		0
Total assets	5,905,158	7,680,782
Additions of property and equipment	710,102	90,109
Electrical Power [Member]
Revenue	19,406,225	36,056,446
Depreciation and amortization	232,902	440,968
Income (loss) before income taxes from continuing operations	2,042,469	(11,316,553)
Goodwill		0
Total assets	4,650,077	10,270,446
Additions of property and equipment	$ 203,036	$ 153,906