Question

Maximum useable frequency (MUF) in F-region layer is x, when the critical frequency is 60 MHz and the angle of incidence is 70°. Then x is

• A. (a) 150 MHz
• A. (b) 170 MHz
• A. (c) 175 MHz
• A. (d) 190 MHz

Answer 1

(c)

Sol. Maximum Useful Frequency

$MUF = \frac{f_{c}}{\cos\theta} = \frac{60}{\cos 70{^\circ}} = 175MHz$