10GHz transverter modification

Finally got around to swapping out the 220R 1206 resistor in the input pad of my Kuhne 10GHz G2 transverter kit. The new 39R is the unmarked green 1206 below the BSP171. Been in a bag in my junk box since 1983.

Still a bit of flux and some fluff and muck to remove with the very wonderful Techspray E-Line defluxer pump-spray thingy before the lid goes back on. http://uk.farnell.com/techspray/1621-400s/flux-remover-398ml-spray-bottle/dp/2501335

kuhne-g2-3cm-modification

I can now drive the 3cm board past the 1dB compression point with 18dBm out of my G4DDK Anglian 144MHz transverter. It looks like the 3rd-order IMD products are acceptable up to about 17.7dBm output with a pair of tones 1.4kHz apart at about 14dBm per tone.  Hard to see in the plot because of all the phase noise from the external LO.

Kuhne-3cm-2toneThe CW output at that setting is 21.2dBm, cable loss in the lead to the analyser is 2.6dB.

Kuhne-3cm-cw1

It remains to be seen how good the IMD/ACPR result will be when I get he proper local oscillator built.

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