Baofeng UV-5RM Compliance Test

Compliance testing to ascertain if this radio meets ITU guidelines for spurious emissions.

Baofeng UV-5RM Final Grade: FAIL

The Baofeng UV-5RM UV-5RM failed our test on VHF 2m. It passed on UHF very cleanly and was entirely acceptable at 1.25m, but its 2m performance was out of specification with ITU guidelines.

It is important to note that this was a single-sample test and that it is possible other samples could vary in performance.

Tests performed in Surrey, BC, Canada on August 17, 2024 by Reg Natarajan.
Discuss this radio on our forums. https://forums.advancedamateur.ca/t/baofeng-uv-5rm

Power Output Testing

Power output was measured using a Surecom SW-33 Plus into a dummy load. The radio was set to maximum power. The ITU guidelines for spurious emissions require measurements of "the power (W) supplied to the antenna transmission line". That requirement makes this separate power measurement necessary, as it is incorrect to measure relative to the fundamental (f0). All numbers have been rounded.

2M

146.520 Mhz

6.7 watts

Using the ITU formula of 43+10log(P) dB, spurious emissions for a signal of 6.7 watts must be at least 51.3 dB below the power supplied to the antenna transmission line. 6.7 watts is approximately 38.3 dBm, which means no spurious signal may exceed -13 dBm, or approximately 50 microwatts.

70cm

446.000 Mhz

7.5 watts

Using the ITU formula of 43+10log(P) dB, spurious emissions for a signal of 7.5 watts must be at least 51.8 dB below the power supplied to the antenna transmission line. 7.5 watts is approximately 38.8 dBm, which means no spurious signal may exceed -13 dBm, or approximately 50 microwatts.

1.25M

223.500 Mhz

5.1 watts

Using the ITU formula of 43+10log(P) dB, spurious emissions for a signal of 5.1 watts must be at least 50.1 dB below the power supplied to the antenna transmission line. 5.1 watts is approximately 37.1 dBm, which means no spurious signal may exceed -13 dBm, or approximately 50 microwatts.

Spurious Emissions Testing

Spurious emissions were measured using a Tiny SA Ultra. The radio was set to maximum power and was connected to the TinySA through an attenuator. It is important to understand that the graphs below are using a decibel scale, not a linear scale. If a spurious emission spike appears to be almost as tall as the fundamental, that does not mean it is emitting almost as much power. Refer to the raw data shown.

VHF 2m Band Test Results: FAIL

Raw Data 2m

All numbers have been rounded

Power at Antenna: 38.3 dBm (6.7 watts)

Fundamental (f0): 36.7 dBm (4.7 watts)

2nd Harmonic (2f0): 10 dBm (10 milliwatts)

Should be less than -13 dBm (50 microwatts)

3rd Harmonic (3f0): -11.6 dBm (70 microwatts)

Should be less than -13 dBm (50 microwatts)

4th Harmonic (4f0): -12.9 dBm (51 microwatts)

Should be less than -13 dBm (50 microwatts)

The Baofeng UV-5RM sample that we tested displayed three noticeable harmonic emissions above the 2m band fundamental, one of which was out of compliance with ITU guidelines. Any spurious emissions should be at least 51.3 dB below the power measured at the antenna transmission line. The UV-5RM's second harmonic was just 28.3 dB below, which is out of specification.

UHF 70cm Band Test Results: PASS

Raw Data 70cm

All numbers have been rounded

Power at Antenna: 38.8 dBm (7.5 watts)

Fundamental (f0): 37.9 dBm (6.1 watts)

The Baofeng UV-5RM sample that we tested displayed no significant spurious emissions above the 70 cm band fundamental in our testing. There was one minor spike at the second harmonic that was well within ITU guidelines.

220 1.25M Band Test Results: PASS

Raw Data 1.25M

All numbers have been rounded

Power at Antenna: 37.1 dBm (5.1 watts)

Fundamental (f0): 35.6 dBm (3.7 watts)

2nd Harmonic (2f0): -20.6 dBm (9 microwatts)

Should be less than -13 dBm (50 microwatts)

3rd Harmonic (3f0): -9.8 dBm (105 microwatts)

Should be less than -13 dBm (50 microwatts)

The Baofeng UV-5RM that we tested displayed two harmonic emissions above the fundamental in the 1.25m band, one of which was out of specification with ITU guidelines by 55 microwatts which we consider to be an acceptable performance.

Comments

Unlike the FCC and IC certified UV-5Rs that we have recently tested, this UV-5RM failed our 2m testing. It's important to note that the spurs amounted to just 10 milliwatts, which is not the worst performance we've seen, but it is enough to trigger a repeater in many cases.

Many thanks to Doug VA7JDJ for the use of his radio for testing.

~Reg Natarajan VA7ZEB / HJ1ZEB, August 17, 2024

Discuss this radio on our forums. https://forums.advancedamateur.ca/t/baofeng-uv-5rm

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