Spectral Purity testing of Baofeng UV5RA

I decided to look at my Baofeng UV5RA spectral purity.  These things have came up many times as being less than clean and failing to meet FCC emissions levels in a lot of examples tested.

I done a test measuring the harmonics of two UV5RA radios and a Yaesu FT817 for comparison.

The results show that the UV5RA radios which I measured do meet the FCC 43db levels, but not by much!  Both UV5RA radios had a very similar output so I’ve only included one set of screen prints from the spectrum analyzer.

UV5-RA at 1MHz with a center frequency of 146.520MHz.  This looks fine.

UV5ra_1mhz

FT-817 at 1MHz with a center frequency of 146.520MHz, also looks fine.  There are some additional sidebands above and below the carrier but still low.  The UV5RA has the edge in this range, but its very slight and not really significant.

FT817_1mhz

 

UV5RA at 500MHz span.

The first harmonic (largest spike) at close to 300 MHz is -45dBm compared to the 0dBm reference.  So just inside the permitted emissions level.  I’m fine with this with the short antenna using it as a hand held radio, but certainly wouldn’t want to use it with a home base antenna and a bit of gain!

UV5ra_500Mhz

 

FT-817 at 500MHz span.  You can see how much cleaner it is.  The same first spike is just noticeable above the noise floor at about -59dBm.

FT817_500Mhz

Conclusion.. they are not great!

 

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