variable frequency

variable-frequency

: 127 phrases in 29 subjects

Agriculture	2	Electricity	4	Oil / petroleum	1
Air defense	10	Electronics	23	Radio	2
Automobiles	2	General	3	Rail transport	3
Aviation	9	Geophysics	5	Refrigeration	1
Bridge construction	1	Hydroelectric power stations	4	Space	3
Communications	1	Information technology	1	Statistics	1
Compressors	2	Mechanics	3	Steel production	2
Construction	1	Metallurgy	2	Technology	24
Earth sciences	3	Multimedia	1	Wind Energy	4
Electric machinery	8	Nuclear and fusion power	1