A detailed review and laboratory test report for the Trio TM2550E 2 m FM mobile transceiver.
The Trio TM2550E is a 2 m FM mobile transceiver designed with a unique feature set, including direct four‑digit frequency entry, up/down scanning, and an automatic repeater‑shift function. It delivers 40 W output power with a low‑power mode of just over 4 W, and offers 23 memory channels, priority monitoring, and a digital front‑panel display.
The document provides both subjective impressions and measured laboratory results, covering receiver sensitivity, selectivity, distortion, audio output power, and transmitter performance such as frequency accuracy, deviation, and tone‑burst stability. A muTek LBPF50u band‑pass filter is also evaluated for use with the rig.
| Output Power (high) | 40 W |
|---|---|
| Output Power (low) | ≈4 W |
| Frequency Entry Method | Direct 4‑digit entry via 4×4 keypad |
| Automatic Repeater Shift Range | 145.6 – 145.845 MHz |
| S‑meter Scale | S1 – S9 (vertical double bars) |
The rig is rated at 40 W high power, with a low‑power button that reduces output to just over 4 W.
Repeater shift activates automatically when you tune or enter a frequency between 145.6 MHz and 145.845 MHz.