SG Labs transverter ⁽¹⁾

This part was going to be about the full transmission path but I am still getting the POTY and LDF4-50A line ready. Instead, I wanted to experiment with the SG Labs 13cm transverter. For the test the FT818 was dusted off and set to 432MHz FM so it would give a constant output when keyes. This fed the transverter, the output of which was put into a dummy load via a 20dB directional coupler that in turn fed a frequency counter. The output was giving 2,404MHz and was nicely stable over a couple of hours (not keyed all the time of course). When finished the transverter will be locked to a 10MHz reference from a GPSDO. The output power was around 18mW, again via the directional coupler, so about 1.8W. The FT818 was not set to full power and the PA, when finally installed has a maximum input of 250mW so some attenuation is still needed. Ok, so I have a full receive path for both transponders, I can decode FT8, hear SSB and see DATV. And I am now happy that I will be able to transmit once the PA and POTY are all in place. My next thoughts…