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    Hi All,

     

    Has anyone experienced this issue other than me? I recently got 'pushed' the Creators Update of Windows 10 and suddenly I get Blue Screens of Death whenever I try to pull a component out of the Altium Vault! (I'm only trying to place a generic 0805 resistor!) This has repeated itself twice. I was happily running Circuit Studio prior to this update, now I can't seem to use the Vault for anything.

     

    Windows 10 Pro :

         Win 10 Pro 64bit, v1703, Build 15063.138

         AMD FX-8350, 16GB RAM

         nVidia GeForce GTX 550 Ti, 1GB GDDR5

     

    Altium Circuit Studio :

         Ver. 1.4.0 (Build 84)

     

    One thing to note, I am trying to create a simple voltage divider for a Simulation. (Maybe I shouldn't be using a component from the Vault for this? Could this be an Altium bug that just wasn't seen until this Windows update?)

     

    Regards,

    Thomas


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    Connectors III

    RF Connectors

    Sponsored by

    1. Introduction 2. Objective 3. Electromagnetic Spectrum 4. RF Waves: AM/FM Bands 5. Coaxial Transmission Lines
    6. Coaxial Connectors 7. Performance Specifications 8. Types of RF Connectors Parts Used Test Your Knowledge

     

    1. Introduction

    The tremendous growth of wireless communication around the world has spawned the development of more types of RF connectors than was ever imaginable a mere twenty years ago. Radio frequency connectors today are providing critical links to a substantial amount of equipment, including networking, cellular communications, radio frequency identification, global positioning systems, mobile radio systems and many more. Understanding the factors that impact the selection as well as the design of RF connectors is essential knowledge for a design engineer who works with RF circuits. This learning module explores the features and applications of the most common types of RF connectors.

     

    2. Objective

    The objective of this learning module is to provide you with the essentials of RF connector technology. You will first review the basics of electromagnetic wave theory. In the later sections, you will gain an understanding of radio waves, coaxial transmission lines, and the common types of RF connectors and their applications.

    Upon completion of this module, you will be able to:

    Define the electromagnetic spectrum

    Discuss the elements of RF coaxial transmission Lines

    List the components, coupling styles, and termination types of coaxial connectors

    Explain the importance of RF performance specifications

    Identify the most common types of RF connectors and their applications

     

    3. The Electromagnetic SpectrumBack to Top

    Radio frequency and wireless communication devices have been built for over a century. Many scientists contributed to their development, including Sir Oliver Lodge, Alexander Stepanovich Popov, Sir Jagadish Chandra Bose, and many others. But it was Guglielmo Marconi’s experimental broadcast of the first transatlantic radio signal in 1901 that ultimately led to the commercial viability and world-wide adoption of RF technology. Devices based on RF technology ranging from radio, TV, cellular and the Internet are so common today that we can hardly imagine a world without them. Before discussing the different types of RF connectors in this learning module, let’s begin with a brief review of the theory behind radio frequency devices, beginning with the Electromagnetic (EM) Spectrum.

    Decades before Marconi's first transatlantic radio broadcast, Scottish scientist James C. Maxwell demonstrated, in the 1860s, that time-varying electric and magnetic fields cause electromagnetic waves to travel in a vacuum at the speed of light. Twenty years later, Heinrich Hertz went on to apply Maxwell's theories and experimentally prove the existence of radio waves in the late 1880s.

    Electromagnetic waves are the result of self-propagating, transverse oscillations of electric and magnetic fields. These fields are perpendicular to each other and to the direction of the wave. Once formed, this electromagnetic energy travels at the speed of light until it interacts with matter.

    The discovery of electromagnetic waves led to the identification of an entire range of EM waves that are together called the Electromagnetic Spectrum (EM). These waves are radiant energy, resulting from electromagnetic interactions. While EM waves are continuous in nature, scientists typically divide the EM spectrum into discrete segments called bands.  The following table describes the EM spectrum's frequency bands:

    Frequency (f) Wavelength (λ) Band Description
    30-300 Hz 104 to 103 km ELF Extremely Low Frequency
    300-3000 Hz 103 to 102 km VF Voice Frequency
    3-30 KHz 100 to 10 km VLF Very Low Frequency
    30-300 KHz 10 to 1 km LF Low Frequency
    0.3-3 MHz 1 to 0.1 km MF Medium Frequency
    3-30 MHz 100 to 10 m HF High Frequency
    30-300 MHz 10 to 1 m VHF Very High Frequency
    300-3000 MHz 100 to 10 cm UHF Ultra High Frequency
    3-30 GHz 10 to 1 cm SHF Super High Frequency
    30-300 GHZ 10 to 1 mm EHF Extremely High Frequency (Millimeter Waves)

    Electromagnetic waves travel at the speed of light in a vacuum. These waves are described by their relationship between frequency (f) and wavelength (λ). Their relationship is shown in the following equation:

    C = f  x  λ
    (with c = 3.0 x 108 m/sec)

    Since the speed of light is a constant (3.0 x 108 m/sec), the equation predicts that as the frequency of an electromagnetic wave increases, its wavelength decreases, and vice versa.

     

    4. Radio Frequency Waves: AM/FM BandsBack to Top

    Radio waves are one of the many types of electromagnetic (EM) radiation or energy; they appear at the lowest frequency portion of the electromagnetic spectrum. They have wavelengths between 1 millimeter and 100 kilometers (or 300 GHz and 3 kHz in frequency).  While radio waves occur naturally in the world, radio waves can be generated by RF devices used in fixed and mobile radio communication, broadcasting, radar, communications satellites, computer networks and more.

    AM and FM bands are the part of the electromagnetic spectrum used for radio broadcasting. In the AM band, radio waves, called "carrier waves," are used to broadcast commercial radio signals in the frequency range from 540 to 1600 kHz. The abbreviation AM stands for "amplitude modulation," which is the method for broadcasting radio waves by varying the amplitude of the carrier signal to be transmitted. The resulting wave has a constant frequency, but a varying amplitude.

    In the FM band, the carrier waves are used to broadcast commercial radio signals in the frequency range from 88 to 108 MHz. The abbreviation FM stands for "frequency modulation," which is the method for broadcasting radio waves by varying the frequency of the carrier signal to be transmitted. The resulting wave has a constant amplitude, but a varying frequency.

    RF technology continues to demonstrate itself as a durable technology with its growing impact on IoT wireless connectivity. Much of today's most popular wireless equipment operate in the 2.4-GHz radio band, including Wi-Fi hot spots and home wireless routers, ZigBee, Bluetooth, some cordless phones, among others. Sub-1GHz radio bands are even finding application in the transceivers and microcontrollers designed for this radio band and destined for use in long-range, wireless IoT networks.

     

    5. Coaxial Transmission LinesBack to Top

    A transmission line is a two-conductor structure that supports the propagation of transverse electromagnetic (TEM) waves (i.e., an electromagnetic wave where both the electric and magnetic fields are perpendicular to the direction of wave propagation). It is designed to transmit RF power in the most efficient manner from one point to another.  An RF transmission line consists of a source, a load, and the combination of RF cable and connectors. Coaxial lines are the most common type of RF transmission line.

     

    - 5.1 Coaxial Cables

    Coaxial cables are specially constructed cables with a core center conductor, surrounded by a tubular non-conductive insulator (dielectric), which is then enclosed by an braided copper shielding (the outer conductor). The dielectric separates the core inner conductor from the outer shielding conductor. The coaxial cable's outer shielding is typically protected by PVC material.

    Coaxial cable is designed to keep the RF waves inside the cable while keeping out magnetic interference. It does so by effectively placing two wires in one structure, each with current moving in opposite directions that cancel out the currents due to the proximity effect thereby preventing RF radiation.  Coaxial cable is ideal for applications where attenuation must be kept to a minimum and the elimination of outside interference is critical.

    - 5.2 Impedance Matching

    Transmission lines must be impedance matched over the entire coaxial structure in order to prevent reflections of the signal at the line terminations. If the impedances aren’t matched, maximum power will not be delivered (from source to load) and standing waves will develop along the line.

    In a transmission line, the source, line and load impedances must be matched for maximum power transfer to occur. In other words, ZS = Z0 = ZL

    - 5.3 PCB Transmission Lines

    Transmission lines can also be constructed utilizing printed circuit board technology. The substrate of the printed circuit board functions as the dielectric and separates the two conductors. The first conductor is typically a narrow etch, while the second conductor is the ground plane.  The most popular types of printed circuit board transmission lines are: microstrip, stripline, coplanar waveguide and slotline.

    The above illustration visualizes a microstrip transmission line utilizing an SMA RF connector.

    Coaxial RF connectors allow a cable to be connected to another cable or component (e.g, printed circuit board) of the RF transmission line structure. There is a wide variety of coaxial connectors designed to fit with different types of coaxial cable. Coaxial connectors will be discussed in the next section.

     

    6. Coaxial ConnectorsBack to Top

    In this section, let's discuss the components, coupling styles, and termination types of a typical coaxial connector.

    - 6.1 Components

    Inner Conductor (Center Conductor): functions similar to a terminal in an electrical connector; it carries the main circuit signal.

    Dielectric: functions as an insulating spacer between the inner and outer conductors.

    Shielding (Outer conductor): provides shielding that keeps interference outside the connector while keeping desirable currents inside. It’s held at ground or reference potential for a circuit path return.

    - 6.2 Coupling Style

    The coupling style is the method used to mate a coaxial plug to a coaxial connector or receptacle. There are four types of coupling mechanisms used with RF connectors, including: Threaded, Bayonet, Snap-On and Slide-On.

    In general, threaded styles maximize mating security. They are used in high vibration environments. Snap-on devices provide the quickest mating. Bayonet couplings offer a compromise between ease of use and mating security. Slide on coupling provides quick and easy installation.

    The coupling style also impacts performance. As with electrical connectors, higher performance RF products require exceptionally tight, stable mating interfaces to minimize noise and optimize energy transfer. Traditionally, threaded couplings have provided this integrity. Today, however, non-threaded coupling technology have advanced significantly to provide the same benefit and often in a small footprint.

    - 6.3 Terminations

    Coaxial cables are typical terminated with RF connectors. Coaxial connectors are designed to maintain a coaxial form across the connection and have the same impedance as the attached cable. Coaxial connectors can be terminated in the following ways: Plugging, Soldering, Crimping, Clamping, Pressing and Threading.

     

    7. Performance SpecificationsBack to Top

    Now that you understand the physical features of coaxial connectors, let's consider their performance. There are many factors that determine the performance of RF coaxial connectors, but the four main specifications are:

    Frequency range: Each coaxial connector series supports a specific frequency range. A connector's frequency rating is typically determined by the internal geometry of the coaxial structure with which it is used. Conductor sizes and the type and amount of insulation between them determine this spec. In general, higher frequency connectors tend to be smaller in diameter and have tighter tolerances.

    Impedance: Impedance can be thought of as the total resistance a system offers to the flow of RF waves. For maximum power transfer of RF energy, impedance should be matched throughout the entire coaxial structure. If the coaxial structure is not impedance matched, parts of the RF waves reflect back toward their source, decreasing energy transfer and flow efficiency. In addition, the reflections may distort the waves to the point where the information they carry cannot be accurately interpreted. Most RF application manufacturers design their products for either of the two industry-standard cable impedance ratings: 50 Ohm or 75 Ohm. 50 Ohm cable is commonly used for radio transmitters and receivers, laboratory equipment, and data communications. 75 Ohm cable is typically used in video applications, CATV networks, TV antenna wiring, and telecommunications.

    Voltage standing wave ratio (VSWR): While it's theoretically possible to achieve perfect impedance matching, it's not usually cost effective.  There will always be reflections. How much reflection an RF connector introduces is stated in its VSWR (Voltage Standing Wave Ratio) specification. VSWR expresses the reflected signal as a ratio to the pure signal; it measures the impedance matching of loads to the characteristic impedance of a transmission line. Impedance mismatches result in standing waves along the transmission line. An ideal VSWR would be 1.00, indicating that all RF energy passes through the connector. The VSWR should be as low as possible.

    Intermodulation distortion: intermodulation distortion (IMD) is the amplitude modulation of signals containing two or more different frequencies, caused by nonlinearities in a system. This expresses the signal distortion from factors caused by poor design and manufacturing, bad grounds, corrosion, low contact pressure, etc. These problems generate unwanted frequencies that distort the original signal, inhibit its ability to carry data without errors, and impede accurate demodulation. Some typical contributions to intermodulation distortion are: oxidized metal contact surfaces, current saturation, and oil or grease layers between contacts.

     

    8. Types of RF ConnectorsBack to Top

    There are many types of coaxial connectors. This learning module will discuss on the most common types, categorized by size.

    - 8.1 Miniature RF Connectors

    MOLEX  73100-010573100-0105 RF Coaxial Connector BNC Coaxial Right Angle Jack Solder 50 ohm Phosphor Bronze

    The BNC connector is one of the most common types of coaxial cable connectors. BNC connectors are used with miniature-to-subminiature coaxial cable in radio, television, and other radio-frequency electronic equipment, test instruments, and video signals. It features two bayonet lugs on the female connector. Mating is fully achieved with a quarter turn of the coupling nut. BNC Radio Frequency (RF) Connectors ensure proper operation and signal integrity throughout the entire broadcast-transmission line. They can transmit signals up to 12 GHz and exceed performance requirements of serial-data transmission for high-speed, high-definition TV (HDTV), HD video and broadcast applications.

    MOLEX  73216-271073216-2710 RF Coaxial Connector TNC Coaxial Right Angle Jack 50 ohm Phosphor Bronze

    The TNC connector is a threaded version of the BNC connector designed for demanding, high-vibration and harsh environments. It is commonly used in mobile communications, avionics and antenna ports for wireless base units. TNC miniature performs at a constant 50 Ohm impedance. The stability of the threaded coupling allows the connectors to perform up to 11 GHz with improved resistance to adverse environments. It has better performance than the BNC connector at microwave frequencies.

    - 8.2 Subminiature RF Connectors

    MOLEX  73298-003073298-0030 RF Coaxial Connector BMA Straight Plug Crimp 50 ohm RG55 RG142 RG223 RG400

    BMA connectors are an ideal solution for high-frequency performance rack and panel RF applications up to 22 GHz. BMA connectors are available in both fixed and float mount versions to allow for rack and panel mount applications where axial and radial float are needed. The BMA design has protected spring contacts that assure reliable, damage-free mating. They have blind mating capabilities up to 1.27mm axial and 0.5mm radial misalignment.

    Type F Connector

    The Type F connector is a coaxial RF connector commonly used for "over the air" terrestrial television, cable television and universally for satellite television and cable modems. In the 1970s, Type F connectors became commonplace on VHF television antenna connections in the US, as coaxial cables replaced twin-lead cables. They have a threaded coupling style to ensure the connector will not decouple in high vibration applications. They are designed for use from DC to 4 GHz.

    MOLEX  73403-626373403-6263 RF Coaxial Connector FAKRA II SMB Coaxial Straight Plug Crimp 50 ohm RG174 RG316 Phosphor Bronze

    FAKRA and FAKRA II SMB connectors are specifically designed for automotive telematic applications. Standard uses for FAKRA connectors are coaxial connections on devices with external antennas such applications include SDARS, Cellular, GPS Navigation, key-less entry and satellite radio. A 360° rotation inside the plastic shroud provides ease-of-routing and less stress on the cable. A secondary locking latch delivers easy cable routing between antennas and multi-media units. The connector is color coded and keyed shrouds prevent mismating and helps guide proper connection. It has a frequency range from DC to 4 GHz.

    SMP Jack SMP Plug

    The ever increasing need for higher density and lighter weight electronics within today's systems requires compact connections. SMPM RF Blind-Mate board-to-board and cable connections deliver the needed density in a high-performance connector. Providing superior frequency performance from DC to 65 GHz, the SMPM connector also compensates for the axial and radial misalignment issues inherent with board-to-board mating.

    SMP subminiature connectors offer excellent performance from DC to 40 GHz. PCB mount, cable mount and in-series adapters provide an interconnect solution for board-to-board and blind mate applications while maintaining package density. SMP connectors are also available in multi-port solutions. Interface styles include smooth, limited detent and full detent to cover a wide range of applications.

    MOLEX  73174-004073174-0040 RF Coaxial Connector DIN 41626 DIN 1.0/2.3 Right Angle Jack Through Hole Vertical 50 ohm

    DIN 1.0/2.3 connectors are compact RF/microwave connectors for applications where space limitation is a factor. They allow up to 1.00mm of axial engagement tolerance, providing excellent flexibility when mating orthogonal PCBs. They enable transferring multiple RF signals across mated boards in a single assembly. 50 and 75 Ohm designs ae available. Some versions of the 50 Ohm design are capable of operating to 10 GHz. DIN 1.0/2.3 connectors are also available in a Modular Backplane System that enables system designers to improve system routing of RF signals for board-to-board communications. They conform to CECC 22 230, DIN 47297 and DIN 41626.

    QMA Jack QMA Plug

    Developed as an alternative to the threaded SMA connector, the QMA connector is one of the most popular coaxial connectors in use today. Performance is comparable to a threaded SMA with the benefit of a faster installation and removal as well as higher density. This design can save handling time because it allows quick mating and demating without tools. Due to the smaller overall size, it can save the operating space and allows for high density arrangement. To make cable routing easier, it can rotate 360 degrees after installation. It is rated from DC to 18 GHz.

    SMA Jack SMA Plug

    SMA Connectors are high-performance subminiature connectors for microwave frequencies. The threaded coupling insures uniform contact of the outer conductors, which enables the SMA to minimize reflections and attenuation at higher frequencies while providing a high degree of mechanical strength and durability. SMA connectors are available in brass, beryllium copper and stainless steel materials. SMA Connectors are optimized for high performance, operating to 27 GHz.

    SMB Jack SMB Plug

    SMB connectors are a subminiature connector series designed for applications operating to 4 GHz and are available in 50 and 75 Ohm versions. This series includes a snap on interface, controlled by industry standard specifications and is easy to connect and disconnect. Mechanical stability provided by the SMB interface, and its relative small size allows uses in applications where space is limited.

    - 8.3 Microminiature RF Connectors

    MMCX Jack MMCX Plug

    Microminiature connectors are finding their way into an ever growing list of smaller, denser applications, such as switching equipment, cellular handsets, and mobile computers. Ideal for space-critical applications, MMCX connectors are compact and lightweight connectors that provide reliable electronic performance from DC to 6 GHz. Their mechanical stability is maintained via a snap-on interface that does not use slotting in the outer conductor. Typical applications include wireless/PCS devices, telecommunications, GPS receivers and consumer electronics. For medical MRI applications, non-magnetic versions are available.

    MCX Jack MCX Plug

    MCX subminiature snap-on connectors offer a stable and durable connection. Their subminiature design allows other electronic assemblies to be densely packaged on the PCB. MCX connectors are approximately 30% smaller than SMB connectors. They are available in both 50 and 75 Ohm versions and provide good electrical performance to 6 GHz. These connectors are used in telecommunications systems as well as wireless and GPS applications. For medical MRI applications, non-magnetic versions are available. Multi-port MCX connectors for coplanar board-to-board and cable-to-board applications.

    - 8.4 Ultra-microminiature RF connectors

    SSMCX Jack SSMCX Plug

    Super Snap-on MCX (SSMCX) or ultra microminiature connectors are designed for electronic applications with size and weight limitations while maintaining good RF characteristics. SSMCX connectors are approximately 35% smaller than MMCX connectors; they are available in 50 and 75 Ohm versions. The extremely small size makes SSMCX connectors are an ideal solution to create multi-port, high-density RF applications.They are  commonly used in board-mount applications, such as handheld devices and notebook PCs, where the jack is edge-mounted. They have a frequency range from DC to 6 GHz. A low-loss cable version is available to provide greater signal strength. It has a mechanical latch to ensure connectors are securely mated and to prevent accidental un-mating. Metal PCB board-lock posts provides proper PCB alignment, added strength, secure PCB retention during and after soldering.

    - 8.5 Medium RF Connectors

    MOLEX 73100-003373100-0033 RF Coaxial Connector N Coaxial Straight Jack Crimp 50 ohm RG58 RG141 RG303

    Type N connectors balance frequency and power by providing a low-loss interconnect up to 11 GHz for high-power RF applications. Type N connectors have a miniature classification; however, it is medium size in use. They accommodate a wide range of medium to miniature-sized RG coaxial cables in a rugged medium-sized design. Type N connectors can provide low-loss interconnects to 11 GHz, optimized precision versions are available up to 18 GHz. The screw-type coupling combined with the larger size, provides a robust design and proper fit for some larger coaxial cables. A durable threaded coupling ensures connector will not decouple in vibration intention applications. Applications include broadcast electronics, aerospace, telecommunication base stations and the passive/active components used in base stations.

    - 8.6 Large RF Connectors

    DIN 7/16
    Jack
    DIN 7/16
    Plug

    7/16 DIN connectors are designed for rugged, low-loss, high-power wireless infrastructure systems. They are designed for a wide range of cables, including corrugated styles. Silver or tri-metal (Copper, Tin and Zinc) plating is used for low Inter-modulation Distortion (IMD). The tri-metal plating is tarnish resistant and durable and provides abrasion resistance comparable to nickel with far better electrical performance. Tri-metal plating alloys are non-magnetic which is critical for low IMD. They are rated from DC to 7 GHz. They have an easy-Hex coupling nut to allow toolless application.

    - 8.7 Multi-Port (Ganged) RF Connectors

    Ganged Jack

    Ganged Plug

    As applications become increasingly smaller and functionality requirements continue to grow, there has become a need for greater density and convenience. Multi-port (Ganged) RF connectors permit mass mating of RF circuits. They mitigate the risk of I/O coax connection failure in high-vibration environments with rugged and compact MPRF connectors. Cable weight under vibration can compromise connections and cause system failure in small multi-port connectors when terminations twist and/or move within the housing. Designed with dual side latches, MPRF connectors ensure reliable I/O connection by preventing cables from moving or twisting within the ruggedized housing even in high-vibration environments.

    *Trademark. Molex® is a trademark of Molex Corporation.  Other logos, product and/or company names may be trademarks of their respective owners.

     

    Shop our wide range of power, signal and data connectors, accessories and adapters.

    Shop NowShop NowShop NowShop NowShop NowShop Now

     

    Test Your KnowledgeBack to Top

    Are you ready to demonstrate your RF Connectors knowledge? Then take a quick 20-question multiple choice quiz to see how much you've learned from this Essentials Connectors 3 module.

    To earn the Connectors 3 badge, read through the module to learn all about RF connectors, complete the quiz at the bottom, leave us some feedback in the comments section and then download the attached Connectors 3 PDF (below) for future reference.

     

    1) The TNC connector is a threaded version of the BNC RF connector. The threaded coupling provides what benefit?





     

    2) For maximum transfer of RF energy, impedance should be matched throughout the entire coaxial structure (source, line and load).





     

    3) What feature of a QMA RF connector enables easy cable routing?





     

    4) True or False: Radio waves are a form of energy in the modification of velocity-dependent electric and magnetic fields.


     

    5) The enOcean Pi features a radio transmitter that transmits radio messages at either 868 MHz, 315 MHz or 902 MHz. What EM band are these frequencies?





     

    6) You need to select an RF connector for a densely populated electronic module that's destined to be installed in an environmentally controlled environment. What category of RF connector is the best choice for this application?





     

    7) RF is an electromagnetic wave that travels at the speed of light in a vacuum. RF waves are described by their relationship between _________ and _________ .





     

    8) What is the most efficient method of transporting RF signals from one point to another point?





     

    9) True or False: The Voltage Standing Wave Ratio (VSWR) is a numerical measure that describes how well an antenna is impedance matched to the radio or transmission line.


     

    10) RF Connectors have which of the following coupling mechanisms?





     

    11) What type of RF connector has a self-aligning feature that compensates for a small misalignment when mating?





     

    12) What component of an SMA connector minimize reflections and attenuation at higher frequencies while providing a high degree of mechanical strength and durability?





     

    13) 7/16 DIN connectors are ideal for what type of application?





     

    14) True or False: Fakra RF connectors are designed for on-board automotive telematics.


     

    15) In a PCB transmission line, what is the function of the PCB substrate?





     

    16) What is the wavelength of an EM wave with a frequency of 3 MHz?





     

    17) True or False: Electromagnetic waves are the result of oscillation of electric and magnetic fields. These fields are in opposition to each other and to the direction of the wave.


     

    18) Why does coaxial cable prevent the radiation of RF waves outside the cable?





     

    19) True or False: A transmission line must be impedance matched to prevent magnetic interference.


     

    20) What type of connector mitigates the risk of mass I/O coaxial connection failure in high-vibration environments?





    Alas, you didn't quite meet the grade. You only got %. Have another look through the course, and try again.
    You nailed it, and scored %!  To earn the Connectors 3 badge, leave us some feedback in the comments section and then download the attached Connectors 3 PDF for future reference.  Other topics you want to learn? Send a suggestion.

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  • 04/22/17--22:33: UpCycle IT - R2I - Research
  • UpCycle IT – R2I INDEX:

     

    Blog #1_”Introduction”

    Blog #2_”Designing”

    Blog #3 "The Kit"

    Blog #4_"Mother Natures Version"
    Blog #5_"Research"

     

    Blog #5 - Research

     

    ResearchIsWhatIAmDoing.jpg

     

    So under Hobbies, I believe Researcher is a very appropriate label for me.  :-)  Especially as I delve in the varied aspects of melding technology and farming.

     

    Here is some of the interesting information I came across while researchingincubation for chickens.  The distinction of chickens is important since various fowl incubation differ quite a bit from temperature and humidity to time of incubation.

     

    Basic Information:

     

    Generally there is some basic information shared for incubation of chickens manually:

     

    1.  Obtaining fertile eggs.  It is important to obtain fresh fertile eggs.  No you can not use eggs purchased at the local grocery store and found in their refrigerators.  I will obtain mine from our own hens.  I will not know if they are all fertilized though so there is a chance of mixed results.  We believe a hawk recently took out one of our Roosters and this of course is a required item for fertilized eggs!

     

    2.  Temperature varies if you are doing a "Still-Air" or "Forced-Air" implementation.  If you not implementing a fan, then you want the temperature to be at 101.5, measured at the top of the egg.  If you are using a fan then a temperature of 99.5 is a good setting.

     

    3.  Minimum number.  As I mentioned above I will not know if all of my eggs have been fertilized as such setting at least 6 eggs improves the chances of having some successful chicks hatch and reach maturity.  Another factor is size of incubator, if you get a massive incubator that can hold 250 eggs then they will probably have a minimum number required to meet the temperature and humidity needed/expected.

     

    4.  Approximately 21 days for Chicken eggs to hatch.

     

    5.  Humidity should be between 40-50% for the first 18 days of incubation.  After you should raise it to 70%.

     

    6.  Unlike our Easter Egg pictures, the egg should not be placed with the pointy tip up.  The wide tip (or bottom for most) should be elevated if possible or at the least the small tip should be as low as it can be placed.  ChickenEggX.jpg

     

    7.  Egg turning, at least 3 times a day.

     

     

    Now this is just some basic information that seemingly can be found everywhere from 4H groups to survivalists to hobby farm user groups.  Many of them may make their own incubator from a Styrofoam box and manually roll their eggs themselves 3 times a day with a handy dandy calendar beside the incubator to appropriately mark each turn and milestone.

     

    They may even have invested in an incubator that has a rolling mechanism to gently roll them on their sides automatically.

     

    What was a little more interesting to me was reading on how commercial incubators operate and the level of studies and experiments that have went on to verify amount of times the egg should be turned and the minimal angles needed.

     

    Commercial level Information:

     

    There are a lot of educational links (as in College/University) showing that at one time the chicken egg was quite an interesting academic study.  Surprisingly most seem to be non-functioning now. 

     

    One of the best solid sources I have found is

    Pas Reform Hatchery Technologies

    They provide some pretty interesting reasons why things are done a certain way commercially.  Such as why they place the eggs with the point down an why this can be a serious problem when human error mistakenly places them with the point up. 

     

    There is a 12-30 percent reduction in the potential hatching of your eggs when the egg is placed point up.  "A hatchery loses 0.2 per cent of sellable chicks for each 1 per cent of fertile eggs placed with the small end up in a setter tray (Bauer et al, 1990)." 

     

     

    Flock Large end up Small end up
    A Hatchability (%) 97.6 79.5
    Cull (%) 0.0 3.6
    Grade-A chicks (%) 97.6 75.9
    B Hatchability (%) 96.9 71.8
    Cull (%) 3.0 4.3
    Grade-A chicks (%) 93.9 67.5
    C Hatchability (%) 100.0 84.0
    Cull (%) 2.0 4.0
    Grade-A chicks (%) 98.0 80.0

    Reference: Bauer F., Tullet SG and Wilson HR (1990). Effects of setting eggs small end up on hatchability and posthatching performance of broilers.

    What does this mean?  Approximately 280,800 chicks will be lost per year from a commercial hatchery that does 1 million chicks a week.

     

    Commercial hatcheries have large shelves (setting trays) that rotate their eggs the proper 45 degrees while keeping their eggs in a vertical position with the tip down.  After the 18th day the eggs are transferred to a hatcher tray where they will remain on their sides for the last 3 days and humidity is increased.

     

    Taking this information into account has heavily influenced my design for my Refrigerator 2 Incubator project.  Please keep following along to see it as it develops!


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    Questions about risk management

    In the comments to my last week blog postmcb1 and DAB brought to my attention importance of exception handling.

    The following questions needs to be answered:

    1. What happens when communication from a detector not received in a preset time?
    2. How to verify connections and operating of sensors?
    3. What happens when there is more then one detector in the same area and one of them stops reporting?
    4. What happens when the only detector is in 'maintenance' or removed?

     

    Make it safer

    I decided to revisit the original design to address the first and the second question. At least I'll know when I'm at risk.

    I've added two new error processing components. One is internal Error Processing deployed on Intel Edison. It's main responsibility is to communicate errors from other processing components and monitor detectors disconnects. In addition, it will establish a heartbeat communication with External Monitoring. In case internal Error Processing fails, the External Monitoring will detect loss of communication and will send alert ("deadman switch").

     

    monitor with heartbeat

    External Monitoring

    On the role of External Monitoring I'm considering a Cronitor service. It has capability to detect disconnection, has integration with Slack. This integration with Slack channel requires only configuration changes.

    Cronitor + Slack setup

    Cronitor service has several options. I've chosen Free Cronitor option. This service is free for a single monitor, but can be extended if required.

    The code for the hearbeat is pretty straightforward:

    // Heartbeats API setup
    var heartbeats = require('heartbeats');
    
    // a heart that beats every 5 minutes.
    var heart = heartbeats.createHeart(5*60*1000);
    var request = require('request');
    
    heart.createEvent(1, function(count, last){
    var ping = 'https://cronitor.link/'+process.env.CRONITOR_MONITOR+'/complete?auth_key='+process.env.CRONITOR_AUTH_TOKEN;
    
    request(ping, function (error, response, body) {
       if (!error && response.statusCode == 200) {     console.log(body);   }
     });
    });

     

    When the monitor goes done, then Cronitor communicates alert to Slack and sends another message when heartbeat recovers:

    Cronitor+Slack

    I still need to add functionality to Error Processing component. But it will be covered next week. Stay tuned.


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    << Previous Blog Index Coming soon >>

    This week I played a lot with the Edison software tools. In my fourth blog I described my first steps using the Arduino SDK. As I was not completely happy with that, I switched to XDK, Node.js and Node-RED. I also detected that my firmware wasn't updated by then. This is also fixed now.

    Node-RED is a visual programming environment. To be honest normally my preference does not ly with visual programming, I rather prefer Matlab for instance above LabView. Nevertheless for this application Node-RED works very well, so I would give it a try. Please read on for all the details.

     

    Setting up the Edison (update)

    In blog post [Upcycle It] Nixie Display #4 - Got Started with the Intel® Edison Development Board on macOS I explained how the operating system was installed and setup using macOS. Unfortunately I detected that there wasn't a new system installed. The Edison just ran from its preinstalled image. After some experimenting I discovered that the problem was caused by the USB connection to my laptop by means of a USB hub. After connecting the Edison directly to the laptop USB port I could install the latest Edison image:

     

    root@edison_arduino:~# cat /etc/version

    201606081705

    root@edison_arduino:~#

     

    Then I configured the device name, password and wifi from the command line:

     

    root@edison_arduino:~# configure_edison --setup

     

    Next I found an addressing conflict with the Edison's USB Gadget driver network with my own home network. They both operate at 192.168.2.* and due to the conflicting address space I couldn't use the WiFi connection. This could easily be solved by editing /etc/systemd/network/usb0.network and changing  the default usb0 ip address (192.168.2.x). When I turn usb0 down or keep it up using a different ip (example: 192.168.5.15) everything works fine. More info here: https://communities.intel.com/thread/101731.

     

    root@edison_arduino:~# cat /etc/systemd/network/usb0.network

    [Match]

    Name=usb0

     

    [Network]

    Address=192.168.5.15/24

     

    root@edison_arduino:~#

    Intel XDK

    Next I installed the Intel XDK and tried the blinking LED demo as described on the intel getting start page https://software.intel.com/en-us/xdk/docs/getting-started-intel-xdk-nodejs-iot. After the first connect to the board it took quite some time for updating all the necessary software components on the Edison. After a reboot of the board I could upload and run the blinking  LED application without any problem.

    Here is the console log:

    Intel XDK - IoT App Daemon v0.1.6 - Node: 4.4.3, Arch: ia32

    Upload on board is not from current project - uploading complete project

    transferring /tmp/xdk-1173ZPBm6hm0KAE4.tar from project to board

    x LICENSE.md

    x README.md

    x main.js

    x icon.png

    x package.json

    x utl/cfg-app-platform.js

    x utl/version-compare.js

    x xdk/project-info.json

     

    IMPORTANT: Executing NPM on IoT target. Wait for "Upload Complete" message before you start your app.

    install complete

    Upload Complete

    Not auto starting by request

     

    Initializing IoT LED Blink

    node version: 4.4.3

    mraa version: v1.0.0

    mraa platform type: 2

    mraa platform name: Intel Edison

    os type: Linux

    os platform: linux

    os architecture: ia32

    os release: 3.10.98-poky-edison+

    os hostname: edison_arduino

    Using LED pin number: 13

    Remember the problems I had starting the arduino sketch on boot time ([Upcycle It] Nixie Display #4 - Got Started with the Intel® Edison Development Board on macOS).

    With Node.js and XDK this works flawlessly. Just select 'Board Configuration' from the manage button,

    Intel®_XDK 2.png

    and check the 'Run previously loaded application at startup' checkbox.

    Intel®_XDK 3.png

     

    Then I tried the I2C LCD demo from the available templates. I modified the code a bit:

     

    /*
     * Drive the Grove RGB LCD (a JHD1313m1).
     *
     * This can be done using one of two methods:
     *
     * Use the UPM library, which contains direct support for the LCD device.
     *
     * Alternatively, in this app, we will drive the LCD directly from JavaScript
     * using the I2C interface directly. This approach is useful for learning
     * about using the I2C bus. The LCD file is an implementation in JavaScript
     * for some common LCD functions.
     *
     * Supported Intel IoT development boards are identified in the code.
     *
     * See LICENSE.md for license terms and conditions.
     *
     * https://software.intel.com/en-us/xdk/docs/using-templates-nodejs-iot
     */
    
    
    /* spec jslint and jshint lines for desired JavaScript linting */
    /* see http://www.jslint.com/help.html and http://jshint.com/docs */
    /* jslint node:true */
    /* jshint unused:true */
    
    
    "use strict" ;
    
    
    // we want mraa to be at least version 0.6.1
    var mraa = require('mraa');
    var version = mraa.getVersion();
    
    
    if (version >= 'v0.6.1') {    console.log('mraa version (' + version + ') ok');
    }
    else {    console.log('meaa version(' + version + ') is old - this code may not work');
    }
    
    
    useLcd();
    
    
    /**
     * Rotate through a color pallette and display the
     * color of the background as text
     */
    function rotateColors(display) {
        var red = 0;    var green = 0;    var blue = 0;    display.setColor(red, green, blue);    setInterval(function() {        blue += 64;        if (blue > 255) {            blue = 0;            green += 64;            if (green > 255) {                green = 0;                red += 64;                if (red > 255) {                    red = 0;                }            }        }        display.setColor(red, green, blue);        display.setCursor(0,0);        display.write('Upcycled NIXIE');        display.setCursor(1,0);        display.write('RGB=' + red + ' ' + green + ' ' + blue + '   ');    }, 1000);
    }
    
    
    /**
     * Use the hand rolled i2c.js code to do the
     * same thing as the previous code without the
     * upm library
     */
    function useLcd() {
        var i2c = require('./i2c');    var display = new i2c.LCD(0);    display.setColor(0, 60, 255);    display.setCursor(1, 1);    display.write('hi there');    display.setCursor(0,0);    display.write('more text');    display.waitForQuiescent()    .then(function() {        rotateColors(display);    })    .fail(function(err) {        console.log(err);        display.clearError();        rotateColors(display);    });
    }

     

    And here is the result:

    IMG_2686.JPG

    So far my experience with Node.js is positive and for the Edison I prefer this above the Arduino SDK.

     

    Node-RED

    Nice aspect of Node.js is that you can run nice stuff on top of it, such as Node-RED (https://nodered.org/ ) jasonwier92 already described some experiments with Node-RED (Getting To Know the Sensors with Node-Red [Upcycle It #3]). As you might remember from my [Upcycle It] Nixie Display #1 - Introduction I want to display weather, or other data from the internet on the Nixie display. Node-RED should make that perfectly possible using the node-red-node-openweathermap (http://flows.nodered.org/node/node-red-node-openweathermap).

    Lets give it a try: (my procedure is slightly different from jasonwier92's)

     

    root@edison_arduino:~# npm install --unsafe-perm node-red

    root@edison_arduino:~# cd /usr/bin

    root@edison_arduino:~# ln -s /home/root/node_modules/.bin/node-red node-red

    root@edison_arduino:~# ln -s /home/root/node_modules/node-red/bin/node-red-pi node-red-pi

    root@edison_arduino:~# cd

    root@edison_arduino:~# npm install -g pm2

    root@edison_arduino:~# pm2 start node-red --node-args="--max-old-space-size=128"

    root@edison_arduino:~# pm2 save

    root@edison_arduino:~# pm2 startup

    root@edison_arduino:~# reboot

    I skipped all the informational commands in the listing above, as they are not necessary, although very informative.

    A video of the complete proces can be found here: (https://youtu.be/28fknvDEAwc )  at 18:50 the installation of Node-RED starts.

     

    In order to control the grove starter kit sensors I need to install a node library for that. First one I found (http://flows.nodered.org/node/node-red-node-upm ) looks promising:

    root@edison_arduino:~# npm install node-red-contrib-upm

    root@edison_arduino:~# reboot

    I tried die LCD module, but unfortunately that didn't work, I got a "TypeError: LCD.Jhd1313m1 is not a function" error when deployed.

    Next I found a library with nodes from seed studio (http://flows.nodered.org/node/node-red-contrib-smartnode-seeed ):

    root@edison_arduino:~#  node-red-contrib-smartnode

    root@edison_arduino:~#  node-red-contrib-smartnode-seed

    root@edison_arduino:~# reboot

    That one worked, with three simple blocks I got a clock up and running, here is a picture of the flow:

    Node-RED___192_168_2_40.png

    The timestamp injects the number of milliseconds since January 1st, 1970 into the flow. The 'numdate' is a function node in which I put code to convert the time number to a readable time string:

     

    // Create a Date object from the payload
    var date = new Date(msg.payload);
    // Change the payload to be a formatted Date string
    msg.payload = date.toString();
    // Return the message so it can be sent on
    return msg;

     

    And the screen node is the LCD screen from the node-red-contrib-smartnode-seed node. As you can see the info field has the Chinese locale. That doesn't influence its functionality, but would be nice if there also is a english translation available. I will have a look at that later.

    So using this three simple blocks I built a clock. What also is very convenient is that it automatically starts when powering up the edison.

    IMG_2691.JPG

    As you can see it is displaying GMT time, which is not my timezone. This could easily be fixed by changing the local time file:

    root@edison_arduino:~# rm /etc/localtime
    root@edison_arduino:~# ln -s /usr/share/zoneinfo/Europe/Paris /etc/localtime
    root@edison_arduino:~# reboot
    ...................................
    root@edison_arduino:~# date
    Sat Apr 22 17:20:44 CEST 2017

     

    Thats it for this week, Node-RED looks like the ideal candidate to continue my project .

    Next steps will be to test the node-red-node-openweathermap (http://flows.nodered.org/node/node-red-node-openweathermap) node and make a Node-RED node for connecting to the PCF8574 I/O extenders in order to control the Nixie tubes.

    But first I need to work on the hardware. Last week my PCB's arrived, I will blog about that next week.

     

    Stay tuned.


    0 0

    This week’s update is about the temperature sensors and dealing with the possibility of moisture issues.

     

    First is the temperature sensors:

     

    I finally received the temperature sensors yesterday!! I have been working most of today with Energia to get them working. At the time of writing this blog I am still working on the script. I will post an update blog when it’s up and running. The sensors are the DS18B20 Temperature Sensors. OneWire requires a single 4.7K pullup resistor, connected between the pin and +5 volts. Then just connect each 1-wire device to the pin and ground. Some 1-wire devices can also connect to power, or get their power from the signal wire. It looks like I made a bit more work for myself ordering this type of sensor.This Maxim series temperature sensor works on the Maxim OneWire protocol which needs a single contact serial interface. I downloaded the libraries “OneWire-master” and “Dallas Temperature” then transferred them into the libraries folder in Energia. It looks like I will be doing some re-programming of my script to get the MSP432 to read the sensors. At least I can move forward on my project!!

     

     

    This information was copied from https://www.pjrc.com/teensy/td_libs_OneWire.html

     

     

    Basic Usage

    OneWire myWire(pin)

    Create the OneWire object, using a specific pin. Even though you
    can connect many 1 wire devices to the same pin, if you have a large number,
    smaller groups each on their own pin can help isolate wiring problems. You can
    create multiple OneWire objects, one for each pin.

     

    myWire.search(addrArray)

    Search for the next device. The addrArray is an 8 byte array. If
    a device is found, addrArray is filled with the device's address and true is
    returned. If no more devices are found, false is returned.

     

    myWire.reset_search()

    Begin a new search. The next use of search will begin at the
    first device.

     

    myWire.reset()

    Reset the 1-wire bus. Usually this is needed before communicating
    with any device.

     

    myWire.select(addrArray)

    Select a device based on its address. After a reset, this is
    needed to choose which device you will use, and then all communication will be
    with that device, until another reset.

     

    myWire.skip()

    Skip the device selection. This only works if you have a single
    device, but you can avoid searching and use this to immediatly access your
    device.

     

    myWire.write(num);

    Write a byte.

     

    myWire.write(num, 1);

    Write a byte, and leave power applied to the 1 wire bus.

     

    myWire.read()

    Read a byte.

     

    myWire.crc8(dataArray, length)

    Compute a CRC check on an array of data.

     

     

     

    Second is the moisture issue:

     

    I have purchased a liquid that can be applied to the electronic circuits that protects them against moisture and other environmental concerns. I added the product description below. The cost was $23 cdn through Amazon.

     

    MG Chemicals Acrylic Lacquer Conformal Coating

     

    • 419C Acrylic Conformal Coating is an IPC 830 certified, fast drying, xylene and toluene free product that provides an excellent finish. It is easy to use and does not require special or costly equipment to apply
    • It is ideal for high moisture environments and applications requiring easy repair and rework
    • The 419C coating protects electric circuit against moisture, dirt, dust, thermal shocks, and scratches that could corrode, short circuit, or otherwise damage the electric component
    • It insulate against high-voltage arcing, shorts and static discharges; this coating provides high dielectric withstand voltage allows traces to be put closer together helping with miniaturization

     

    Product description

    419C Acrylic Conformal Coating is an IPC 830 certified, fast drying, xylene and toluene free product that provides an excellent finish. It is easy to use and does not require special or costly equipment to apply. It is ideal for high moisture environments and applications requiring easy repair and rework. The 419C coating protects electric circuit against moisture, dirt, dust, thermal shocks, and scratches that could corrode, short circuit, or otherwise damage the electric component. It insulates against high-voltage arcing, shorts, and static discharges. As well as, this coating provides a high dielectric withstand voltage that allows traces to be put closer together helping with miniaturization. Super fast cure - reduces production and maintenance bottlenecks. No hazardous air pollutants - free of toluene and xylene. Externally qualified to IPC-CC-830B by Pacific Testing Laboratories, Inc. Meets UL 94V-0. UL Recognized. Excellent finish - smooth, homogeneous, and durable crystal clear coat. Protects electronics from moisture, corrosion, fungus, and static discharges. Easy to inspect - fluoresces under UV. Easy rework and repairs - can solder through coat; remove with MG Chemicals Thinner/Cleaner or Conformal Coating Stripper. Visual crystal clear color. Excellent solderability, weather resistance, fungus resistance, flexibility, moisture and insulation resistance and thermal shock. 94V-0 Flammability. Ether-like, gasoline and minty odor. 3-5 minutes tack free. 2 minutes recoat time. 24 hours full cure (at room temperature). 30 minutes full cure (at 65 degree C /149 degreee F). -65 to 125 degree C service temperature. Less than 12 800 sq cm (less than 13.7 sq ft) maximum coverage for 25 micrometer (1 mil). ROHS Compliant.

     

    Thank you

     

    Dale Winhold


    0 0

    Hello,

     

    On circuitstudio website there is a sample of a schematic:

    VCC and GND net/wire have both a special color and width.

    Is there a way to have those attribute automatic?


    0 0

    I am hoping that a new HAT we have designed and released will be of interest to anyone wanting to control motors within their own projects using the Raspberry Pi computer.

    4F-1.png

    The Pulse Train Hat is an add-on board for the Rapsberry Pi computer and allows clean, fast and accurate pulses to be created using simple ASCII commands.

     

    There are many hardware designs where a variable frequency pulse is needed, but one that is the most popular is for driving stepper/servo motors that use pulse and direction lines.

    Motors like this are found in machines such as 3D Printers, CNC machines, Robot Arms and not to mention the other endless motion control and automation machines.

     

    Below is a Test Rig we used while developing the code.

     

    It allows us to test all 4 channels of the PTHAT by sending the pulses to stepper drivers, that were connected to small Nema 17 motors. It also has all the limit switch inputs brought out to switches, the ADC inputs connect to 10K pots and AUX outputs connected to LED’s.

     

    We decided to use low cost stepper drivers that are usually found in 3D printers as they are not brilliant, but do the job. Our thinking is if the PTHAT can control these noisy little drivers, then handling the more expensive drivers would be easier!

     

    PTHAT-Test-Rig.jpg

     

    Controlling motors may seem simple, but when you get down to detailed control, it can all become very confusing and a big learning curve.

     

    With the new Pulse Train Hat (PTHAT) add-on for the Raspberry Pi and a new dedicated support site http://www.pthat.com , we plan to make that task very simple and allow everyone to easily create their automation product.

     

    Pthat-RaspberryPI.jpg

     

    We have created an number of example applications using Visual Studio 2015 that can be used with Windows 10 IOT.

    These examples have been written in C# as a Universal Windows Platform (UWP) and all the source code can be downloaded from the website.

     

    SMALLPulseTrainScaraExample.jpg

    PTHAT-Parallel-Scara2.jpg

     

    SMALLPulseTrainHatSerialExample.jpg

    SMALLPulseTrainHatCoiWinderScreenshot.jpg

    PTHAT-Coil-Winder-2.jpg

     

    We have also designed the PTHAT to have it's firmware upgraded easily using a JTAG programmer that we supply with each board.

    Also full details on the ARM processor we use has been released covering all the GPIO information, Clock settings and peripherals for people wanting to write their own firmware.

     

    ClockSettingsPTHATV1.jpg

     

    Also there are a number of wiring diagrams released covering various stepper driver hook ups.

    BothBoardsTogether-MotorWiring.jpg

    Of course you do not have to use the PTHAT to control motors and can be used as a pulse generator for other projects.

     

    scope10000Hz3.jpg

     

    scope1-2-4-8kHz3.jpg

     

    Please feel free to check out the dedicated support site for more information http://www.pthat.com


    0 0
  • 12/06/16--19:22: Import CubeMX project
  • Hi,

     

    Is there an easy way to import a cubeMX project from GNU Arm Eclipse ?

     

    Thanks

    Elie