Abstract: An experimental system of a small monolithic radial transmission line is established. This line with hyperbolic characteristic impedance is composed of 2 aluminium-alloy plates with a distance of 1 cm. One output port is placed at the center, while 20 input ports are placed uniformly at the outer circumference. Therefore, the maximum number of input pulses of this line is 20. The line is entirely immersed into deionized water, which makes its one-way transmit time 15 ns. The matched load is composed of 20 154 in parallel. The output voltage obtained in experiment is very close to the result of 3-dimensional electromagnetic simulation. Moreover, by investigating the output voltage with different numbers of input pulses, it is found that the amplitude of the lines output voltage is nearly proportional to the number of input pulses when the number of input pulses is small.