I’m still waiting on my LimeSDR Mini, but I recently picked up a 1950s transistor shortwave radio, and wanted to use the LimeSDR to generate the test signals into the IF mixer to align the radio. From a software perspective I’m comfortable with how to generate the signals, but I’m wondering about how to go about attaching the output of the Lime to the mixer of the receiver circuit without damaging the Lime.
I have a Ham It Up v1.3 which will do the downconversion to the 455kHz IF frequency of the receiver.
The alignment procedure calls for connecting an RF generator with a 400Hz tone AM modulated on a 455kHz carrier connected through a 0.05mfd capacitor to the mixer base which is exposed as a lug on the PCB.
Does anyone have any advice on hooking this up without blowing the TX side of the Lime?