This manual covers safety warnings, FCC compliance, and step‑by‑step instructions for installing the battery pack, connecting accessories, and operating the TH‑225A. It explains the functions of each control, the display indicators, and how to use features such as tone squelch, offset/frequency selection, and power‑save mode.
The specifications section lists the frequency range, power output, battery requirements, dimensions, and weight. Optional accessories such as the programmable tone decoder (TSU‑4) and various mounting brackets are also described.
| Frequency range | 144.000–147.995 MHz |
|---|---|
| Mode | FM |
| Operating temperature | 20 °C to +50 °C |
| Antenna impedance | 50 Ω |
| Battery pack voltage | 6.3 V–15 VDC (12 VDC nominal) |
| Low transmit power | 0.5 W (13.8 V) < 0.7 A |
| Receive mode current | ≈ 50 mA |
| Battery saver mode current | ≈ 11 mA |
| Dimensions (W×H×D) | 68 mm × 19 mm × 37 mm |
| Weight (with battery and antenna) | ≈ 600 g |
Match the concave part at the bottom of the radio to the convex part at the top of the battery pack, then turn the battery pack clockwise until it clicks.
Kenwood recommends using the PB‑3 or PB‑4 Ni‑Cd battery pack for long transmission or extended operation.
The TH‑225A operates from 144.000 MHz to 147.995 MHz.