  We present the design and experimental characterization of a
kinetic-inductance traveling-wave parametric amplifier (KI-TWPA) for sub-GHz
frequencies. KI-TWPAs amplify signals through nonlinear mixing processes
supported by the nonlinear kinetic inductance of a superconducting transmission
line. The device described here utilizes a compactly meandered TiN microstrip
transmission line to achieve the length needed to amplify sub-GHz signals. It
is operated in a frequency translating mode where the amplified signal tone is
terminated at the output of the amplifier, and the idler tone at approximately
2.5~GHz is brought out of the cryostat. By varying the pump frequency, a gain
of up to 22 dB was achieved in a tunable range from about 450 to 850~MHz. Use
of TiN as the nonlinear element allows for a reduction of the required pump
power by roughly an order of magnitude relative to NbTiN, which has been used
for previous KI-TWPA implementations. This amplifier has the potential to
enable high-sensitivity and high-speed measurements in a wide range of
applications, such as quantum computing, astrophysics, and dark matter
detection.
