Shared Projects

STX3 Radio for PyBoard

Convert the 14-pin Xilinx JTAG connector from 2.00mm to 2.54mm. It turns out some devices use the 2.54mm (0.1") pin spacing, which is not the default for the Xilinx USB Platform cable.

sourDough soic20 Breakout, for Narrow or Wide packages. Tested, good.

UNTESTED, DO NOT BUY.

3.3V, and 5V breadboard power. 500mA max output. Fixed vreg pads. Final draft.

UNTESTED! DO NOT BUY!

sourDough JST Breakout w/ Switch, based on Adafruit design.

UNTESTED! DO NOT BUY!

sourDough JST Breakout, based on Adafruit design.

nRF52 add-on board for Butterfly, perfect as a UART bridge to stream serial over BLE to a smart phone or laptop.

For the AquaMaster Project

A Low Noise Amplifier (PSA4-5043+ or similar) for SDR use, intended to be remotely located at the antenna (so powered up the coax cable using a bias-T). The PCB includes provision for various SAW and LTCC pre-filters (or a zero ohm link), a 5V regulator (if needed), various BNC and SMA types of connectors and a miniature relay module which enables use of the antenna (no LNA or filter) when the pcb is not powered . The PCB will slide perfectly into a SZOMK AK-C-B7 aluminium enclosure.. (search google or aliexpress.com), just drill holes in the endplates for your chosen connectors.

E Field Active Antenna

Chebyshev Band-Pass Filter SMA

Chebyshev Band-Stop Filter SMA

LNA with Pre Filter For Case

LNA For Alu Case

Tricorder Head Unit Board (Version 0.1.0) Documentation and CAD files are being updated on GitLab at https://gitlab.com/richteel/TOSTricorder/tree/v2.0.0.0

Tricorder Main Board v0.0.1 NOTE: There are a few issues with this board. (Pi Pogo Pins are misaligned and resistors are missing for Sparkfun GPS.) Documentation and CAD files are being updated on GitLab at https://gitlab.com/richteel/TOSTricorder/tree/v2.0.0.0

Stronger, simpler touch wheel for Deja

This QRE1113 Sensor Board can be used as a Line Sensor, quadrature encoder pickup, object detector, etc. It supports three different modes of operation, configurable, via component selection, as: Raw Sensor, Analog Output Sensor, or Digital Output Sensor.

When assembling, select the desired board mode type of raw, analog, or digital depending on your application. The first value listed for each component is the ‘raw’ mode value. The second is the ‘analog’ mode value. The third is the ‘digital’ mode value. “NC” means “No Component”. For example, for a digital mode board, use R1=150 Ohms, R2=220 Ohms, and R3=0 Ohms (jumper), and RC1=10nF (or 0.01uF) capacitor.

All surface mount resistors and capacitors are 1206 footprint for simple, easy hand assembly.

The Pinout in Digital and Analog modes is:

• 1) 5V+ Power In
• 2) Ground
• 3) Ground
• 4) Output

The Pinout in Raw Sensor mode is:

• 1) A (Anode)
• 2) K (Cathode)
• 3) E (Emitter)
• 4) C (Collector)

This board is similar to the two SparkFun Line Sensor Breakout boards https://www.sparkfun.com/products/9453 and https://www.sparkfun.com/products/9454, only more generic in that the same board can be configured either way or used as a raw sensor connection, such as for use with my Modulated Reflectivity Sensor Driver Shield.

The part selection, as detailed on the silkscreen, is identical to the SparkFun design except for the current limiting resistor for the sensor’s Infrared LED. I selected 150 Ohms and the SparkFun design uses 100 Ohms. The difference is approximately 25mA vs 38mA through the LED. The LED is rated at a max of 50mA. According to sensor datasheets, the peak wavelength output characteristics are achieved at 20mA. The higher current may help for slightly longer distance sensing, but will consume more power. You decide which one you wish to use.

For schematics, refer to the SparkFun schematics at the above links for the Digital and Analog modes. The Raw Mode is simply the four pins of the sensor routed to the connector.

The connector chosen is a 4-pin JST XHP series, 2.5mm connector. However, given the minimal difference between 2.5mm and a 0.100" or 2.54mm pitch connector, you should be able to also use a regular 0.100" pitch header connector if so desired.

NOTE: The 10K value shown for RC1 for ‘analog’ mode is low enough to keep the sensor’s phototransistor in the linear region. To push it into the switching region, use a 47K resistor instead to increase the gain nearly five times and make it function adequately for most applications. This is an example where Pololu got it right, but SparkFun didn’t, in my opinion. But, it depends on your application and whether you want the phototransistor in the linear region or switching region.

Source at github

This is the power-management block of Manuvr’s motion-capture glove. It has been broken out as a module for testing and re-use.

Intended usage

A software-mediated single-cell li-ion battery manager for cases needing bursts of a few watts and supporting long periods of quiescent standby.

Features

• Fused battery
• Charger and fuel gauge are both i2c
• Secondary regulator has three voltages (0, 2.5, 3.3), and can be changed dynamically.
• Integrated 4-bit level-shifter (i2c capable)
• 2.54 headers
• Single-sided assembly for easy thermal-relief

Primary components

Constraints

• Battery must be li-ion chemistry.
• Primary regulator is always on and fixed at a 3.3v output.
• No single regulator may provide more than 1.8A, and the module’s maximum output wattage is 4.2 watts. See below.

Charge and discharge rate on the battery must not exceed 1A, or the internal sense resistor in the fuel gauge will burn out. There is a resetable fuse to prevent damage, but this forms the limit on the module’s practical output rating. However, the charger IC can handle up to a 20v input, and could conceivably draw more than the module’s maximum output from the input source as it charges and powers the load. Fuse accordingly. :-)