Eric Brombaugh designed this ADC board for RF signals:
This is an ADC designed for use in digitizing RF signals with up to 40MHz bandwidth and 80dB SNR. The form-factor is compatible with a dual-connector Digilent Pmod so that it can be used with commonly available FPGA development boards to build a variety Software-Defined radio functions.
- ADC14C105 14-bit 105MSPS RXADC.
- Onboard 3.3V Regulator (5V input)
- Filtered Analog 3.3V Supply
- Onboard 80MHz clock oscillator
- Digilent-compatible 2-connector Pmod interface
- 50-ohm SMA input – 2.5Vpp ~= 0dBfs
emeb has shared the board on OSH Park:
Joe Crop is a creating a real life version of this famous sci-fi device:
In the true spirit of Star Trek, this communicator badge is completely autonomous, while fitting in the form factor of an original badge
Star Trek was known for dreaming up technology that was deemed nearly impossible given the limitations of the technology for the day. Having a small badge that could send audio across vast distances seemed out of the realm of possibility during the late 1980’s. This project’s aim is to use modern technology to provide nearly all the features of visionary tech, namely:
– Tap to connect and communicate instantly
– Long range (from orbit to planet surface)
– Small form factor (of an original TNG badge)
– Fully autonomous (no cell phone or base station needed)
– No external power source (i.e. battery powered)
joecrop has shared the board on OSH Park:
We like the novel orientation of pogo pins that Wing Tang Wong used in this board design:
Upcycles D1 Mini Wemos board to create a USB connected ESP8266 Pogo pin jig
This is a board designed to take a WeMos D1 Mini board(with the ESP module removed) and use it as a USB interface with built-in reset/flash functionality for bare ESP8266 modules similar to the ESP-12 units.
The design files are available on GitHub:
Eric Brombaugh designed this breakout board for the Rafael Microelectronics R820T2 Advanced Digital TV Silicon Tuner chip:
This is the same chip used in most all of the RTL-SDR dongles, as well as the Airspy and numerous other radios. The chip is a versatile front-end with reasonable sensitivity and wide tuning range.
The design presented here is almost an exact implementation of the Mfg’s suggested demo design from the datasheet, implemented on the OSHpark 4-layer PCB process and provides a simple 4-pin interface with power, ground and I2C bus for controlling the tuner. A broad-band RF input and 10MHz IF output are provided on SMA connectors.
The breakout PCB design and STM32F0 firmware for the Rafael R820T2 tuner chip are shared on GitHub:
emeb has shared project on OSH Park:
My Omega2 Onion shield, using a AMS1117 for 3.3V and CH340G for USB to serial. Kind of ugly soldering here as I didn’t have a tip for the syringe to dispense solder paste, so I just smeared it all over and hoped it reflowed well. It kind of did, but I had a solder blob short on pin 14 +15 on the CH340G, so I just lifted those two legs off the board. I was so eager to get this board tested that I forgot to check that I had these 2mm pin headers. I had just enough to get this thing tested. Time to order more 🙂
Jensa has shared the board on OSH Park:
Simple breakout board using the dirt cheap IC’s CH340G ($0.30/each on ebay) for Serial and a AMS1117-3.3 ($0.025/each) for power. Breaks out all pins from 2mm to 2.54mm headers. Plugs nicely into two small breadboards for prototyping.
Bob Baddeley writes on Hackaday:
There are certain design guidelines for PCBs that don’t make a lot of sense, and practices that seem excessive and unnecessary. Often these are motivated by the black magic that is RF transmission. This is either an unfortunate and unintended consequence of electronic circuits, or a magical and useful feature of them, and a lot of design time goes into reducing or removing these effects or tuning them.
You’re wondering how important this is for your projects and whether you should worry about unintentional radiated emissions [..]
Another good guide is Michael Ossmann’s simple RF design rules:
This shield for the D1 Mini ESP8266-based development board adds a joystick and three buttons, so that you can implement menus or games on your device easily.
deshipu has shared the board on OSH Park: