[regveg] was trying to find a method to receive signals outside the typical 64-1700MHz variety his TV tuner software application defined radio dongle can get. After discovering a few $100+ upconverters on the Internet, he stumbled across a diy project that greatly expands the frequencies his RTLSDR can receive.
[George]’s upconverter utilizes heterodyning to boost the frequencies got by a SDR dongle. The fundamental concept is mixing a signal from an antenna with a 100MHz frequency oscillator. The resulting output will be λ + 100MHz and λ – 100MHz, enabling for a broader variety of frequencies that can be received by the SDR TV tuner dongle.
Now [regveg] has a board as well as schematic that makes it possible to get just about anything with his TV tuner dongle. Interestingly, this upconverter consists of less than $10 in parts as well as is quickly etched at house thanks to a single-sided building as well as through-hole parts.
As a little aside, [Andrew] sent in a idea a few days back telling us his RTL dongle didn’t have any type of ESD protection. This is a extremely poor thing, however the great news is the repair is extremely cheap: just solder in a 10 cent diode as well as you’re great to go.