Yaesu VX6
 Compliance Test

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

Yaesu VX6 Final Grade: PASS

The Yaesu VX6 amateur radio sample we tested performed exceptionally well across all bands, with no spurious emissions exceeding ITU guidelines.

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

Tests performed in Surrey, BC, Canada on July 6, 2024 by Reg Natarajan.
Discuss this radio on our forums.  https://forums.advancedamateur.ca/t/yaesu-vx6

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

4.6 watts

Using the ITU formula of 43+10log(P) dB, spurious emissions for a signal of 4.6 watts must be at least 49.6 dB below the power supplied to the antenna transmission line.  4.6 watts is approximately 36.6 dBm, which means no spurious signal may exceed -13 dBm, or approximately 50 microwatts.

70cm

446.000 Mhz

4.3 watts

Using the ITU formula of 43+10log(P) dB, spurious emissions for a signal of 4.3 watts must be at least 49.3 dB below the power supplied to the antenna transmission line.  4.3 watts is approximately 36.3 dBm, which means no spurious signal may exceed -13 dBm, or approximately 50 microwatts.

1.25M

223.500 Mhz

1.65 watts

Using the ITU formula of 43+10log(P) dB, spurious emissions for a signal of 1.65 watts must be at least 45.2 dB below the power supplied to the antenna transmission line.  1.65 watts is approximately 32.2 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: PASS

Raw Data 2m

All numbers have been rounded

Power at Antenna: 36.6 dBm (4.6 watts)

Fundamental (f0): 35.7 dBm (3.7 watts)

The Yaesu VX6 sample we tested displayed no spurious emissions above the 2m band fundamental that violated ITU guidelines. Power at the antenna was measured at 36.6 dBm and the highest spurious reading was more than 58 dB down, well beyond ITU requirements.   

UHF 70cm Band Test Results: PASS

Raw Data 70cm

All numbers have been rounded

Power at Antenna: 36.3 dBm (4.3 watts)

Fundamental (f0): 34.9 dBm (3.1 watts)

2nd Harmonic (2f0): -19.4 dBm (12 microwatts)

Should be less than -13 dBm (50 microwatts)

The Yaesu VX6 sample we tested displayed no spurious emissions above the 70 cm band fundamental that violated ITU guidelines. Power at the antenna was measured at 36.3 dBm and the second harmonic was more than 55 dB down, well beyond ITU requirements.  All other readings were at least 58 dB down. 

220 1.25M Band Test Results: PASS

Raw Data 1.25M

All numbers have been rounded

Power at Antenna: 32.2 dBm (1.65 watts)

Fundamental (f0): 30.16 dBm (1.04 watts)

The Yaesu VX6 sample we tested displayed no spurious emissions above the 1.25 m band fundamental that violated ITU guidelines. Power at the antenna was measured at 32.2 dBm and the highest spurious reading was more than 57 dB down, well beyond ITU requirements.   


Comments

Many thanks to Adrian VA7YEP for the use of his radio for testing.

~Reg Natarajan VA7ZEB / HJ1ZEB, July 6, 2024


Discuss this radio on our forums.  https://forums.advancedamateur.ca/t/yaesu-vx6