EOS 8/20 microsecond surge protection - STMicroelectronics - Nightly. LLC - Fabricators/Distributors - Nightly. LC Low Pass Filter Circuit :: Radio-Electronics.Com - Nightly. - the design considerations and formulae (formulas) for an LC (inductor capacitor) low pass filter Low pass filters are used in a wide number of applications. Particularly in radio frequency applications, low pass filters are made in their LC form using inductors and capacitors. Typically they may be used to filter out unwanted signals that may be present in a band above the wanted pass band.
In this way, this form of filter only accepts signals below the cut-off frequency. Low pass filters using LC components, i.e. inductors and capacitors are arranged in ether a pi or T network. For the pi section filter, each section has one series component and either side a component to ground. The T network low pass filter has one component to ground and either side there is a series in line component.
LC Pi and T section low pass filters L = Zo / (pi x Fc) Henries C = 1 / (Zo x pi x Fc) Farads Fc = 1 / (pi x square root ( L x C) Hz Further details Care must be taken with the layout of the filter. Simple AlexMos brushless gimbal from Viacopter - RC Groups - Nightly. Like everyone else in the MR community the AutoQuad Team was seeking for a solution for a top notch gimbal control, though the internal camera stabilization of the AQ6 worked pretty well even with cheap gimbal/servo combos.
Spreadsheet for PIDs and other settings for different gimbals/m This video shows the complete setup and tuning process, examplary connected to an AutoQuad FC Thanx to the SBGC project by Alex Moskalenko and the efforts of AQ Team members like Jussi (ViaCopter), Paul (Flyduino), Felix (famous Flyduino NanoWii and UltraESC design) and SebastianJ (Gimbal design) we'll soon have what many desire: an affordable, simple but effective solution for Multirotors - and any vehicle you can think of attaching it to.
I'll try to collect some more info about Alexmos' SimpleBGC as we go... Here you can find more info on the VectorDD / Alexmos brushless gimbal Recommended forum tools:Image BrowserFile Browser Alexmos did it again! Fatshark 600TVL High Resolution FPV Tuned Pan/Tilt CMOS Camera - Nightly. Technology - LTspice Demo Circuits - Nightly. LTspice IV is a powerful, fast and free simulation tool, schematic capture and waveform viewer with enhancements and models for improving the simulation of switching regulators. LTspice provides macro models for most of Linear Technology’s switch-mode DC/DC converters, op amps, comparators, linear regulators as well as a library of devices for general analog circuit simulation including discretes.
Selected Linear Technology devices also have demonstration circuit available for free download. These demo circuits are designed to ensure proper performance and have been reviewed by Linear Technology’s factory applications group. Follow the instructions below to run the demo circuits in LTspice. Step 1. If you do not already have a copy of LTspice, click here to download and install LTspice. Step 2. Has accessories for FPV, UAV, Ham Radio, Robotics, & more! - Nightly. Trm-xxx-dp1203.pdf - Nightly. Orientus | Advanced Navigation - Nightly. RC Groups - View Single Post - APM 2.5 / Ardupilot Mega / RCTimer Arduflyer Discussion Thread (updated 5/8/13) - Nightly. Quote: Is that the 6 pin socket on MimOSD with GND GND +5V RX TX DTR My current limiting 5W 12V globe would have limited total current available from the Lipo to 0.4A and the voltage available to the UBEC would also have been lowered substantially in the process Without my current limiting globe your UBEC would have supplied Maximum current, maybe even failing internally from current beyond its Maximum rating and then supplying full Lipo Voltage and Current.
You do need to test that UBEC to make sure it is now delivering correct Voltage. Which UBEC did you use ? Did the UBEC survive ? Did you have UBEC on Inputs with JP1 removed ? That 6 pin connector PCB layout on MimOSD was done by a well meaning ill informed Amateur who did NOT appreciate nor understand the lengths FTDI went to in designing that 6 pin socket to make it safe from mistakes like yours. Since I can easily make the same mistake, I made my MimOSD safer. Cut 2 traces on the front of PCB Cut 1 trace on the back of PCB. Batsocks - AVR ISP Header Pinouts - Nightly.
There are 6-pin and 10-pin versions. The pinouts are as follows; 6-way header 10-way header For those that are struggling with which way is up (it's one of those things that once you know, you never question again), pretend that the diagrams above are plan-view photographs, and the pins are coming out of the screen towards you. You'd connect a cable by pushing it on towards the screen. The following photographs might be useful; plan view of a simple header a fancy boxed header with a ribbon cable with a different lead Pin 1 is often marked on the board/header in some way.
Protect MOSFET Driver From Reverse-Battery Connection | Power content from Electronic Design - Nightly. Mar. 17, 2003 Mark Cherry | Electronic Design It's vital that MOSFET power-switch drivers be protected from a reverse-battery connection. A small rectifier diode can shield against reversed batteries. But that approach is generally unacceptable for systems whose battery life is crucial. For a 6-V battery, the diode's forward voltage drop (0.6 to 0.7 V typical) produces a constant power loss of approximately 10%.
This loss increases with dwindling battery voltage. The approach shown in the figure is an improvement over single-diode protection. A p-channel MOSFET (Q1) protects the driver (U1) from reverse-battery insertion. Connecting a positive battery voltage to the drain of Q1 produces forward bias in its body diode, which clamps the source voltage one diode drop below the drain voltage. An incorrectly inserted battery reverse-biases Q1's body diode. V DS equals the full negative battery voltage when the battery is inserted backwards. RSSI on Frsky V8FR-II - Nightly. Has accessories for FPV, UAV, Ham Radio, Robotics, & more! - Nightly. This compact supply filter helps clean up dirty DC power that often causes lines in wireless video images.
The filter is an LC type that uses large value inductor and capacitor components. Their values are robust enough to remove moderate amounts of power supply noise. The filter reduces DC-DC switcher supply ripple and helps clean noisy power from a shared battery. For example, if your robot or R/C model's main battery also powers the video camera and A/V transmitter, then this LC filter can help reduce the video "noise" that may appear when its electric motor is running.
This filter is used to reduce ripple noise and similar power supply nuisances. Design Update: Beginning with September 2011 production, all PSF-001 filters are compatible with up to 5S LiPo batteries. Installation requires basic soldering experience. Note: Installations with severe power supply noise may not be fully cured with this filter. Features/Specifications L-C Filter circuit reduces DC supply noise. Kalman filters: The on-going “biography” of an idea | Embedded - Nightly.
One of my favorite new books and one I constantly go back to is James Gleick's new opus titled “ The Information . " It is about information theory and Shannon’s contributions, among others, to understanding its implications not only to engineering but to any aspect of research into the natural world. While it is technically rough going sometimes, what brings me back again and again to reading it is that it is “ the biography of an idea ,” as one reviewer said.
While he does not spare the reader by dumbing down the complex technical issues, Gleick is able to interweave this with the intellectual exploits and personal experiences of those who over the last several hundred years have contributed to our understanding. Coincidentally, as I have been reading it, I have also been making my way through “ The normal distribution ,“ Jack Crenshaw’s most recent Insight blog on the importance of the Kalman algorithm in every aspect of electrical engineering and embedded systems design. FET Supplies Low-Voltage Reverse-Polarity Protection | Power content from Electronic Design - Nightly. Tracking planes for $20 or less | Clayton's Domain - Nightly. My new favourite toy is a cheap $20 USB TV tuner. It’s made to receive DVB-T signals, which aren’t even used in North America. So what use could I possibly have for it? Back in February, Linux kernel developer Antti Palosaari discovered that certain USB TV tuners can be configured to send the raw, unprocessed radio signal straight to the computer for decoding in software.
(They use this mode when tuning FM or DAB radio signals. Think of it as the Winmodem approach to radio.) Palosaari realized that by running the right software, almost any radio signal could be received by these tuners. I should note that receiving (and transmitting) radio signals in software is nothing new. Since getting my hands on a compatible TV tuner, I’ve been able to listen to police radio, pager networks, garage door openers, air traffic control, and lots more. So let’s get started! Purchase a USB TV tuner based on the Realtek RTL2832U chip. Batsocks - AVR ISP Header Pinouts - Nightly. Advanced Power Switching and Polarity Protection for Effects - Nightly. Copyright 1999 R.G. Keen All rights reserved. If you're an effects builder or repairer, you know by now that it's a good idea to protect the circuitry in the effect from the consequences of a reversed battery.
While many older effects can withstand a momentary reversal, some more modern components can be damaged if you accidentally touch the battery contacts the wrong way during replacement. Sometimes this is subtle damage. For instance, everyone pretty much knows that CMOS and some opamps can be killed by reversing their power supplies. Ok, so reverse polarity is a Bad Thing. A cleverer arrangement is to put the diode in parallel with the effect so it's reverse biased by the normal polarity. Of course, when the voltage is reversed and the diode keeps the reverse voltage clamped to 0.7V, the diode and the battery are engaged in a duel to the death; the battery is determined to bring the voltage up to its internal voltage, the diode is determined to hold it down. There is a third way. Rtl-sdr – OsmoSDR - Nightly.
DVB-T dongles based on the Realtek RTL2832U can be used as a cheap SDR, since the chip allows transferring the raw I/Q samples to the host, which is officially used for DAB/DAB+/FM demodulation. The possibility of this has been discovered by Eric Fry (History and Discovery of RTLSDR). Antti Palosaari has not been involved in development of rtl-sdr. Specifications¶ The RTL2832U outputs 8-bit I/Q-samples, and the highest theoretically possible sample-rate is 3.2 MS/s, however, the highest sample-rate without lost samples that has been tested wit regular USB controllers so far is 2.4 MS/s.
A stable sample-rate of 3.2 MS/s without lost samples is only possible with the Etron EJ168/EJ188/EJ198 series of host controllers due to their specific maximum latency. The frequency range is highly dependent of the used tuner, dongles that use the Elonics E4000 offer the widest possible range (see table below). Supported Hardware¶ This is the PCB of the ezcap-stick: More pictures can be found here.
Windows¶ RC Groups - View Single Post - APM 2.5 / Ardupilot Mega / RCTimer Arduflyer Discussion Thread (updated 5/8/13) - Nightly. Current Sensing Circuit Concepts and Fundamentals - 01332b.pdf - Nightly. RC Groups - View Single Post - APM 2.5 / Ardupilot Mega / RCTimer Arduflyer Discussion Thread (updated 5/8/13) - Nightly. Pay attention, here comes an interesting finding which may not mean a lot to some. NORMALLY - 3DRradio does NOT work if USB is connected to ArduFlyer.
However there is a way to power ArduFlyer using a USB cable AND have 3DRadio working. Trick is to use the USB cable to only supply 5V power and NOT make an actual USB connection. How do you achieve that ? Connect the other end of the USB cable to a phone charger with a USB connector outlet like this one from HTC which can supply 5V 1A, ArduFlyer only needs about 250mA 3RDadio works, no need to remove props or use a different BEC and Lipo, normal UBEC and ESC can all remain connected quite safe.
It may also be useful when tinkering with ArduFlyer in or near a car or any battery, as there are car USB chargers that output 5V 500mA with input rated at 12V to 24V.. Having a short extension USB cable built into the frame seems like a good idea. RC Groups - View Single Post - Installing Rctimer C&V Sensor 90A to ArduFlyer 2.5 - Nightly. There is a lot of information in this lengthy blog, please read it all, possibly read it more than once, do not start to apply any of the information before you fully understand it all and it actually makes sense to you, if there is anything you are not sure about, ask first, it can save a lot of time, expense and frustration.
My post #6 with up to date links for APM 2.5/ArduFlyer 2.5 is here Obviously you are measuring large currents, you do need thick conductors capable of handling those large currents soldered to the Rctimer Current & Voltage Sensor 90 A [ CS ] board. We are measuring the current flowing through the thick red lead from the Lipo connector to the Power Distribution.. The next choice is up to you, there is no need to use plugs and sockets, there is no good reason why the CS cannot be incorporated permanently into the lead between Lipo connector and Power Distribution. The contents of the CS The CS board in close detail. Tracking planes for $20 or less | Clayton's Domain - Nightly. Current Sensors - Nightly. RC Groups - View Single Post - APM 2.5 / Ardupilot Mega / RCTimer Arduflyer Discussion Thread (updated 5/8/13) - Nightly. Quote: That is wrong Pin 2 is not a GND connection, it was never intended to be a GND connection Pin 2 is a Signal connection for CTS# That simple but fatal error has been copied by many using a 4 pin connector when a 6 pin connector is required and losing their entire Flight Controller.
This is correct FTDI cable - Black wire keyed to BLK ArduFlyer 2.5 cable - Black wire keyed to BLK The 6 pins used on FTDI Cable connector are an accepted STANDARD For example - 3DRadio from 3DR has the 6 FTDI pins labelled correctly You see CTS and NOT GND for pin 2, and BLK is also labelled for mating the BLACK FTDI cable wire. APM2RC - arducopter - Arduino-based autopilot for mulitrotor craft, from quadcopters to traditional helis - Google Project Hosting - Nightly. Wiring up the APM board is easy. Just connect your RC receiver to the Input side (using the special cables that came with your quadcopter kit, or just any female-to-female cables).
And then plug the signals cable from your power distribution board to the Output side. Please note the illustration Below highlights a (TYPICAL) installation. It contains optional equipment including a Camera Gimbal and a Battery Monitor and it utilizes an ESC wired "Y" power connection rather than the power distribution board common to many MultiCopters.
WARNING:The diagram 'Typical QuadCopter Layout shows the gimbal servos connected and powered by the 5V coming from CH10/CH11. Note: the instructions below are for regular RC receivers with PWM output (one cable per channel). The order of pins is shown here: The ground (black) side of each connector should be on the outside, closest to the edge of the board, as shown here with either straight or right-angle connectors: Input Output Note on Paralleling BECs. 3D Robotics APM 2.5+ Autonomous Flight (Part 2 – Setup) » Odd Copter - Nightly. Nightly.