Friday, May 10, 2019

RF Cafe - Microwave & Wireless Engineering

Resources for Radio, Radar, RF, Microwave, & Wireless Engineering. Collection of links to various application notes for different RF Vendors. Links to RF equations, technical data sheets, math notes and much more.

RF Cafe - Microwave & Wireless Engineering

Some important areas
  • RF Engineering Calculators
  • Electrical / Electronics Conversions, Formulas & References
  • Design Data Resources
E-flite Mini Pulse XT - Brushless ESC Waveform - RFCafe

E-flite Mini Pulse XT - Brushless ESC Waveform

This waveform shows the square waves that drives one of the three phases at a relatively low throttle setting (coming from the brushless speed controller). The peak amplitude is constant for all speeds.

"Much more than just a self-serving video of my new R/C airplane flight agility, this model represents a plethora of modern electronics. Although the radio control system in this plane is a standard narrow band FM variety on 72.170 MHz (as opposed to my 2.4 GHz, spread spectrum system), the motor is a state-of-the-art 3-phase brushless model (E-flite 450)with a sensorless electronic speed control (E-flite EFLA331, 20 A)."

FreePCB - PCB editor

FreePCB is a free, open-source PCB editor, released under the GNU General Public License. It was designed to be easy to learn and easy to use, yet capable of professional-quality work.

FreePCB - PCB editor

Some of its features are:
  • 1 to 8 copper layers
  • Board size up to 60 inches by 60 inches
  • Uses English or metric units (i.e. mils or mm) for most functions.
  • Footprint libraries courtesy of Ivex Design International Inc.
  • Footprint Wizard and Footprint Editor for creating or modifying footprints
  • Imports and exports PADS-PCB netlists
  • Exports extended Gerber files (RS274X) and Excellon drill files
Example - Logic Analyzer: This is an open-source logic analyzer called MiniLA contributed by Bob Grieb of the User Forum. The image on right is the Logic Analyzer PCB.

FreePCB - PCB editor

Some Features:
  • Up to 32 channels
  • 128 Kb of memory for each channel
  • Sampling rate up to 100 MHz (timebase in 1-2-5 sequence)
  • Input levels compatible with 3.3V and 5V logic
  • Selectable pretrigger/posttrigger buffer size in 8K step

Tuesday, May 07, 2019

4-20mA Conditioning - XTR101 TI BB

These are Burr Brown Devices from TI. The BB Chips are excellent devices and High Precision, but a bit more expensive. These can be used when customer demands a Higher Quality and Precision. These are good for High Reliability Industrial Instrumentation. - delabs

4-20mA Conditioning - XTR101 TI BB

The XTR101 is a microcircuit, 4-20mA, two-wire transmitter containing a high accuracy instrumentation amplifier (IA), a voltage-controlled output current source, and dual-matched precision current reference.

4-20mA Conditioning - XTR101 TI BB

The two-wire transmitter allows signal and power to be supplied on a single wire pair by modulating the power-supply current with the input signal source. The transmitter is immune to voltage drops from long runs and noise from motors, relays, actuators, switches, transformers, and industrial equipment.

delabs Schematics