rtl-sdr upconverter

I’ve been productive this memorial day weekend. I ran across a great deal on a digital oscilloscope on Friday. It’s an Aktakom ADS-2061M that was brand new in the box and I got it for the price of a raspberry pi.

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  With that, I was able to put together an upconverter for my rtl-sdr dongle. I used a NE612 mixer with an si5351 oscillator running at 112.5MHz.

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The arduino is driving the si5351 breakout board. I will replace the si5351 with a different oscillator when I make it a permanent installation. I just wanted to see if I could get this to work. It seems to be working great. I’ve got it hooked up to my 40 meter dipole and was getting pretty good reception, even with it mocked up on the breadboard.

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I got the schematic for the upconverter from this reddit post. Here is the relevant piece:

/images/upconverter_schematic.png

All in all the upconverter seems to work well. I plan on adding a low pass filter and a different oscillator and package it up nicely. I also made a Michigan Mighty Mite CW transmitter over the weekend and began work on a paint can dummy load as well, but I’ll add separate posts for those later. Overall, I’ve had a productive holiday.