Hi Vince,
Of the over 30 SHARI UHF kits I have built, I have found the 2nd harmonic is in the range of 44 to 52 dB below the carrier (dBc).? Most are in the 46 to 50 dBc range.? The third harmonic is greater than 60 dBc.? For SHARI's 1/2 watt max output, the requirement is more than 40 dBc.? I use an HP8568B to make my measurements.
As used in SHARI, measured with an HP8753C VNA from the RF output pad of the SA818U through FL1 to the output connector terminated in 50 ohms, I? measured an attenuation of? -1.23 db at 450 MHz, -36 dB at 880 MHz and -40 dB at 1320 MHz.
Steve - N8AR
Steve-N8AR