Maxwell Equation's

Maxwell's Equations - The equations postulated by the Scottish physicist James Clerk Maxwell in 1864 in his article A Dynamic Theory of the Electromagnetic Field are the foundations of classical electrodynamics, classical optics and electric circuits. This set of partial differential equations describes how electric and magnetic fields are generated and altered by each other and by the influence of charges or currents. Maxwell's equations represent one of the most elegant and concise ways to state the fundamentals of electricity and magnetism. From them one can develop most of the working relationships in the field. Because of their concise statement, they embody a high level of mathematical sophistication and are therefore not generally introduced in an introductory treatment of the subject, except perhaps as summary relationships.

These basic equations of electricity and magnetism can be used as a starting point for advanced courses, but are usually first encountered as unifying equations after the study of electrical and magnetic phenomena.

where rot (or curl) is a vector operator that describes the rotation of a three- dimensional vector field,

Equation (1) is Ampere's law. It basically states that any change of the electric field over time causes a magnetic field. Equation (2) is Faraday's law of induction, which describes that any change of the magnetic field over time causes an electric field. The other two equations relate to Gauss's law. (3) states that any magnetic field is solenoid and (4) defines that the displacement current through a surface is equal to the encapsulated charge.

From Maxwell's equations and the so called material equations

it is possible to derive a second order differential equation known as the telegraph equation:

where 𝜀 is the permittivity of a dielectric medium,

          𝜎 is the electrical conductivity of a material,

          𝜇 is the permeability of a material and

        

If one assumes that the conductivity of the medium in which a wave propagates is very small (𝜎 → 0) and if one limits all signals to sinusoidal signals with an angular frequency ω, the so called wave equation can be derived:

The simplest solution to this equation is known as a plane wave propagating in loss free homogenous space. For this wave, the following condition applies:

The vectors of the electric and magnetic field strength are perpendicular to each other and mutually also to the direction of propagation , see figure below.

Consequently the electric and magnetic field strengths are connected to each other via the so called impedance of free space:

Plan wave Description

Reference : Antenna Basic - Rohde & Schwarz

Radiation Pattern

The three-dimensional radiation behavior of antennas is described by their radiation pattern (normally in the far field). As explained before, only an isotropic radiator would exhibit the same radiation in every spatial direction, but this radiator cannot be implemented for any specified polarization and is therefore mainly suitable as a model and comparison standard. 

Dipoles and monopoles possess directivity. An electrically short dipole in free space has a three-dimensional radiation pattern shown in Figure below with nulls in the direction of the antenna's axis.

While the radiation pattern is actually three-dimensional, it is common however to describe this behavior with two planar patterns, also called the principal plane patterns. They can be obtained from the spatial radiation characteristics by looking at a cut-plane - usually through the origin and the maximum of radiation. Spherical coordinates as shown in Figure below are commonly used to describe a location in the three-dimensional space.

The horizontal pattern (see Figure below) shows the field strength as a function of the azimuth angle ϕ with a fixed ϑ (usually ϑ = 90°).

The vertical pattern (see Figure below) shows the field strength as a function of ϑ for a fixed ϕ (usually ϕ = +/- 90 ° or 0°/180°)

Usually antenna patterns are shown as plots in polar coordinates. This has the advantage that the radiation into all possible directions can quickly be visualized. In some occasions (i.e. for highly directive antennas) it can also be beneficial to plot the radiation pattern in Cartesian coordinates - because this reveals more details of the main beam and adjacent side lobes, see figure below.

From the radiation pattern the following additional parameters can be derived (see Figure below)

• The side lobe suppression (or side lobe level) is a measure of the relation between the main lobe and the highest side lobe.
• The half-power beamwidth (HPBW) is the angle between the two points in the main lobe of an antenna pattern that are down from the maximum by 3 dB. It is usually defined for both principal plane patterns.
• The front-to-back ratio specifies the level of radiation from the back of a directional antenna. It is the ratio of the peak gain in forward direction to the gain in the reverse (180°) direction. It is usually expressed in dB.

Reference : Antenna Basic - Rohde & Schwarz

Log Periodic Antenna

Antenna Theory - Log-periodic antenna - The Yagi-Uda antenna is mostly used for long time . However, for better reception  and to tune over a range of frequencies, we need to have another antenna known as the Log-periodic antenna. A Log-periodic antenna with good impedance is a logarithamically periodic function of frequency. 

A special type of directional antenna is the log-periodic dipole antenna (LPDA), where beam shaping is performed by means of several driven elements. The Log Periodic Dipole Antenna is made up of a number of parallel dipoles of increasing lengths and spacing (see Figure 26). Each dipole is fed out of phase to the element on either side by a common feed line. The angle α formed by the lines joining the dipole ends and by the longitudinal axis of the antenna remains constant, as well as the graduation factor 𝜏 which is equal to the ratio of the lengths of neighboring elements and their spacing: 

Log Periodic Dipole Antenna Design (courtesy Rohde & Schwarz)

This antenna type is characterized by its active and passive regions. The antenna is fed starting at the front (i.e. with the shortest dipole). The electromagnetic wave passes along the feed line and all dipoles that are markedly shorter than half a wavelength will not contribute to the radiation. 

The dipoles in the order of half a wavelength are brought into resonance and form the active region, which radiates the electromagnetic wave back into the direction of the shorter dipoles. 

This means that the longer dipoles located behind this active region are not reached by the electromagnetic wave at all. The active region usually comprises of 3 to 5 dipoles and its location obviously varies with frequency. The lengths of the shortest and longest dipoles of an LPDA-Log Periodic Dipole Antenna determine the maximum and minimum frequencies at which it can be used.

Due to the fact that at a certain frequency only some of the dipoles contribute to the radiation, the directivity (and therefore also the gain) that can be achieved with LPDAs-Log Periodic Dipole Antenna is relatively small in relation to the overall size of the antenna. However, the advantage of the LPDA is its large bandwidth which is - in theory - only limited by physical constraints.

The radiation pattern, of an LPDA is almost constant over the entire operating frequency range. In the H-plane it exhibits a half-power beamwidth of approx. 120°, while the E-plane pattern is typically 60° to 80° wide. The beamwidth in the H-plane can be reduced to values of approx. 65° by stacking two LPDAs in V-shape.

Example of a V-Stacked LPDA Antenna

V-stacked LPDA antennas have E- and H-plane patterns with very similar half power beamwidths. Additionally they feature approx. 1.5 dB more gain compared to a normal LPDA.

Radiation pattern of a V-stacked LPDA - E-plane (black), H-plane (blue)

Reference:https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/premiumdownloads/premium_dl_brochures_and_datasheets/premium_

dl_whitepaper/Antenna_Basics_8GE01_1e.pdf

Antenna Impedance Measurement

Input Impedance 

One of the most significant parameters of an antenna is its input impedance: 

𝑍𝑖𝑛 = 𝑅𝑖𝑛 +𝑗𝑋𝑖𝑛 

This is the impedance present at the antenna feed point. Its real part Rin can be split up into the radiation resistance RR and the loss resistance RL 

𝑅𝑖𝑛 = 𝑅𝑅 + 𝑅𝐿 

It should be noted however that the radiation resistance, being the quotient of the radiated power and the square of the RMS value of the antenna current, is spatially dependent. This applies also to the antenna current itself. Consequently, when specifying the radiation resistance, its location on the antenna needs to be indicated.

Quite commonly the antenna feed point is specified, and equally often the current maximum. The two points coincide for some, but by no means for all types of antenna. The imaginary part Xin of the input impedance disappears if the antenna is operated at resonance. Electrically very short linear antennas have capacitive impedance values (Xin < 0), whereas electrically too long linear antennas can be recognized by their inductive imaginary part (Xin > 0).

Nominal Impedance The nominal impedance Zn is a mere reference quantity. It is commonly specified as the characteristic impedance of the antenna cable, to which the antenna impedance must be matched (as a rule Zn = 50 Ω). 

Impedance Matching and VSWR If the impedance of an antenna is not equal to the impedance of the cable and/or the impedance of the transmitter, a certain discontinuity occurs. The effect of this discontinuity is best described for the transmit case, where a part of the power is reflected and consequently does not reach the antenna (see Figure below.) However the same will happen with the received power from the antenna that does not fully reach the receiver due to mismatch caused by the same discontinuity.

Forward and reflected power due to mismatch 

The amount of reflected power can be calculated based on the equivalent circuit diagram of a transmit antenna (see Figure below).

For optimum performance, the impedance of the transmitter (ZS) must be matched to the antenna input impedance Zin. According to the maximum power transfer theorem, maximum power can be transferred only if the impedance of the transmitter is a complex conjugate of the impedance of the antenna and vice versa. Thus the following condition for matching applies: 

𝑍𝑖𝑛 = 𝑍𝑆 ∗ 𝑤ℎ𝑒𝑟𝑒 𝑍𝑖𝑛 = 𝑅𝑖𝑛 + 𝑗𝑋𝑖𝑛 𝑎𝑛𝑑 𝑍𝑆 = 𝑅𝑆 + 𝑗𝑋𝑆 

If the condition for matching is not satisfied, then some power may be reflected back and this leads to the creation of standing waves, which are characterized by a parameter called Voltage Standing Wave Ratio (VSWR). 

The VSWR is defined (as implicated by its name) as the ratio of the maximum and minimum voltages on a transmission line. However it is also possible to calculate VSWR from currents or power levels as the following formula shows: 

Another parameter closely related to the VSWR is the reflection coefficient r. It is defined as the ratio of the amplitude of the reflected wave Vrefl to the amplitude of the incident wave Vforw : 

It is furthermore related to the VSWR by the following formula: 

The return loss ar derives from the reflection coefficient as a logarithmic measure:

 

So there are in fact several physical parameters for describing the quality of impedance matching; these can simply be converted from one to the other as required. For easy conversion please refer to the table below: 

Baluns and Impedance Matching

An Antenna is normally connected to a transmission line and good matching between them is very important. A coaxial cable is often employed to connect an antenna mainly due to its good performance and low cost. A half-wavelength dipole antenna with impedance of about 73 ohms is widely used in practice. From the impedance -matching point, this dipole can match well with a 50 or 75 ohm standard coaxial cable . Now the question is : can we connect a coaxial cable directly to a dipole ?

As illustrated n figure below . when a dipole is directly connected to a coaxial cable, there is a proble: A part of the current comming from the outer conductor of the cable may go to the outside of the outer conductor at the end and return to the source rather than flow to the dipole .

A Dipole Antenna directly connected to coaxial cable 

 This undesirable current will make the cable become part of the antenna and radiate or receive unwated signal, which could be a very serious problem in some cases. In order to resolve this problem, a balun is required.

The term balun is an abbreviation of the two words balance and unbalance. It is a device that connects a balanced antenna ( a dipole , in this case) to an unbalanced transmission line (a  coaxial cable, where the inner conductor is not balanced with the outer conductor). The aim is to eliminate the undesirable current comming back on the outside of the cable. There are a few baluns developed for this important application. Figure below shows two examples . 

Two example of baluns

The sleeve balun is a very compact configuration: a metal tube of 1/4 Lambda is added to cable to form another transmission line (a coax again) with the outer conductor cable , and a short circuit is made at the base which produces an infinite impedance at the open top. The Leaky current is reflected back with a phase shift of 180 degrees, which results in the cancellation of the unwanted current on the outside of the cable. This balun is a narrowband device. If the short-circuit end is made as a sliding bar, it can be adjusted for a wide frequency range (but it is still a narrowband device). 

The second example is a ferrite-bead choke placed on the outside of the coaxial cable. It is widely used in EMC Industry and its function is to produce a high impedance, more precisely high inductance due to the large bandwidth may be obtained ( an octave or more). But this device is normally just suitable for frequencies below 1 GHz. which is determined by the ferrite properties it can be lossy, which can reduce the measured antenna efficiency.

Reference:https://scdn.rohde-schwarz.com/ur/pws/dl_downloads/premiumdownloads

/premium_dl_brochures_and_datasheets/premium_dl_whitepaper/Antenna_Basics_8GE01_1e.pdf

Build This Simple Logic Probe Memory Circuit

Logic Probe Memory Circuit - The Circuit describe is a low cost logic probe with  memory with IC TTL 74107 Dual JK Flip Flop , Diode, resistor, and normaly closed switch provides the probe with memory function that really comes ih handy for "trapping" very fast pulse indications. See the circuit diagram. IC1 used TTL 7404. Used 5V adaptor/or battery.

reference : Popular Electronics  May 1974

Office 365 Backup Solutions

Office 365 backup solutions - Office 365 allows your employees to work anywhere, anytime – and your organization is dependent on it for email communication, team collaboration and document retention. But while Microsoft does an excellent job at taking care of the infrastructure for these services, it’s a misconception that they also take care of your data in the way you might expect.

Microsoft offers backup as part of a shared-responsibility model, meaning they’re responsible for the physical security of their data centers and software failures on their part, but it’s your responsibility to protect your data from cyberattacks and data loss caused by human error, intentional deletion, and programmatic issues.

With the right data protection strategy, of course, businesses can protect data in Microsoft 365 from the threat of loss. That's why a solution is still needed even if you believe your business data is safe in Microsoft 365. One of them is using a cloud backup solution.

In this article we will lists about Best office 365 backup solutions

Office 365 Backup Solutions Software

Acronis

Enhance your managed server backup and recovery

Your clients all have one thing in common, no matter their industry: data loss and downtime are catastrophic to their operations. As a service provider, the quality of the server backup and recovery services you offer matters. Acronis enables you to deliver an integrated solution that combines the most secure server backup available with flip-of-a-switch disaster recovery — all through a single pane of glass.

A global company founded in Singapore in 2003 and incorporated in Switzerland in 2008.

Acronis serving almost 19 years delivering best in class technology with more than 20 thousands Providers, 750 thousands businesses , with 26 languages and more than 15o countries.

Acronis Cyber Protect Cloud by Empowering service providers with backup, DR, cybersecurity, and endpoint management in one integrated solution.

Ancronis Cyber Protect is The unique integration of backup, disaster recovery, cybersecurity, and endpoint management in one solution.

Acronis Cyber Protect Home Office is Formerly Acronis True Image, it's the only personal cyber protection solution that delivers easy-to-use, integrated backup and anti-malware in one

Acronis offering Solutions , For Service Providers Solutions by Managed server backup, Prevention, Managed anti-malware protection, MSP patch management, Recovery, Continuous data protection, Hosting Service Providers

For Business Solutions with Ransomware Protection, Patch Management for businesses, Anti-malware for corporate environments, IT disaster recovery, File Backup and recovery, Data Loss Prevention (DLP), Government and Public Sector (Acronis SCS)

ACRONIS CYBER PROTECT CLOUD INCLUDES: 

• File-level, disk-level, image and application backups

 • Back up popular workloads including Mac, Windows, Linux, Microsoft 365, Google Workspace, Hyper-V, VMware and much more 

• Hybrid storage options – Acronis Hosted Cloud Storage, public clouds such as Microsoft Azure, or MSP local storage

ADVANCED BACKUP ADDS :

Continuous data protection (CDP): Acronis’ agent monitors and backs up changes in real-time with near-zero RPOs, ensuring no data is lost

Storagecraft

StorageCraft Cloud Backup for Office 365 and Microsoft 365

Despite its location in the cloud, Office 365 (O365) and Microsoft 365 data remains vulnerable to acts of human nature.

Microsoft 365 and Office 365, which store files and data in the cloud, demand the same high level of data backup and recovery functions as Microsoft's on-premises version. Microsoft 365 and Office 365 backup solutions must ensure data is protected in the cloud and encrypted while being flexible and easy to use.

Microsoft 365 and Office 365 business data is at risk of incidents such as:

• An employee deleting a file by mistake and then closing the application.
• A disgruntled employee purposely destroying information that is useful to the company
• Someone gaining unauthorized access to company data and deleting files

More and more companies are adopting Microsoft Office 365 for email and collaboration. Using the cloud-based productivity tool, your organization is creating and interacting with information anywhere, anytime, leading to more business data than ever. Your company must oversee and protect all of that data everywhere it goes.

Microsoft Office 365 provides significant advantages to organizations of all sizes; however, this SaaS version of Microsoft’s flagship productivity application, which stores files and data in the cloud, demands the same high level of data backup and recovery functions as it's on-premise version.

Datto

Secure Microsoft 365 Backup & Advanced Threat Protection

Comprehensive detection, protection, and recovery helps you safeguard your clients’ Microsoft 365 data against both known and unknown cyber threats and common data loss scenarios.

Multi-Layered Protection with SaaS Protection and SaaS Defense is SaaS Protection +

Datto SaaS Protection + is built exclusively for MSPs. Combining our SaaS Protection and SaaS Defense tools, this solution scans Microsoft 365 for malicious cyber threats and helps ensure complete protection with 3x daily backups and flexible, fast recovery.

Reliable backup for Microsoft 365

Data stored in SaaS applications face the same risks as any other data. With Datto SaaS Protection +, you can protect against malicious cyber threats and user error, and quickly recover data from the cloud.

Drive SaaS Efficiency

Datto SaaS Protection + for Microsoft 365 is fast, reliable and manageable at scale. You can quickly secure clients with streamlined onboarding and easily manage both quarantined phishing attempts and client backups from a single pane of glass.

Straightforward Billing

Predictable pricing lets you know your costs upfront. The more you sell, the more you'll make, and added discounts applied across all of your licenses mean even more savings.

Shared Responsibility

With Datto SaaS Protection +, you can help your clients streamline data compliance, business continuity, and security.

A Better Together Approach for Microsoft 365

SaaS Protection: Microsoft 365 backup and recovery

Datto SaaS Protection is a backup tool that protects valuable Microsoft 365 data from Exchange, OneDrive, SharePoint, Teams and more.

SaaS Defense: Advanced threat protection and spam filtering

Datto SaaS Defense is a robust threat protection solution for Microsoft 365 applications that proactively detects and helps prevent malicious malware attacks that target Exchange, OneDrive, SharePoint, and Teams.

Protect Vital Microsoft 365 applications

Datto SaaS Protection + is an integrated phishing prevention and backup tool that protects valuable Microsoft 365 data, including Exchange, Calendar, OneDrive, SharePoint, and more.

Protect and Backup Microsoft 365 OneDrive for Business

Protect files in OneDrive with Datto SaaS Protection +. Your clients' files and OneDrive folders will be scanned for malicious malware and be readily available for speedy recovery by utilizing the one-click restore feature.

Protect and Backup Microsoft 365 Exchange Online

Datto SaaS Protection helps keep your mailbox free from phishing attacks, and safely backed up, giving you peace of mind. Your emails, attachments and contacts are protected from downtime and data loss.

Protect and Backup Microsoft Teams

Datto SaaS Protection enables you to protect and backup Microsoft Teams, with a single click. It protects Teams data including the team name, members list and teams channel. You can also recover your clients Microsoft Teams data including team chats, meetings and messages quickly.

Protect and Backup Microsoft 365 Sharepoint

Datto SaaS Protection + is a comprehensive SharePoint backup and recovery solution for MSPs that also delivers phishing protection. It includes all of your site collections, documents, libraries, and lists. Datto SaaS protection can quickly recover your data in the event of an outage.

VeeAM

Veeam Backup for Microsoft 365 is a powerful and versatile backup solution that provides organisations with a simple and reliable way to protect their Office 365 data. The solution can be used to back up mailbox data, OneDrive for Business files, and SharePoint Online data, and can be configured to protect data both in the cloud and on-premises. Veeam Backup for Microsoft 365 also includes powerful recovery options, such as the ability to restore data to any location, including the cloud.

Backup Microsoft 365 (formerly Office 365) data

Microsoft 365 provides powerful services within Office 365 — but a comprehensive backup of your Office 365 data is not one of them. 

Veeam® Backup for Microsoft 365 eliminates the risk of losing access and control over your Office 365 data, including Exchange Online, SharePoint Online, OneDrive for Business and Microsoft Teams — so that your data is always protected and accessible.

Veeam Backup for Microsoft 365 gives you the power to securely backup Office 365 to any location — on-premises or in cloud object storage — including Amazon S3, Azure Blob, IBM Cloud or S3 compatible providers on premises.

eset

When it comes to choosing a backup solution for your business, you can't go wrong with ESET Office 365 Backup. This software is designed to help you protect your data, both on and off your network. ESET Office 365 Backup lets you quickly and easily back up your Office 365 data to a local or remote location, so you can rest assured that your information is safe in the event of a disaster. Plus, thanks to its cloud-based architecture, you can access your backed-up files from anywhere, anytime.

ESET internet security for home users, provide powerful payment and privacy protection for banking and payment protection by secure your online transactions and access to crypto-wallets.

Safely pay online through a special secure browser, or run any supported browser in secure mode by default. Automatically protects you while banking online and accessing web-based crypto-wallets. Encrypts communications between the keyboard and the browser for safer transactions. Protects you from keyloggers.

Firewall, network inspector and more by protect access to your data, network and webcam.

Prevent unauthorized access to your computer and misuse of your personal data. Protect your private data from ransomware. 

Secure your webcam and home Wi-Fi router from intruders and control privacy threats by actively testing your router-connected smart devices.

Parental control as safeguard your kids online and monitor their activities.

Prevent your children from being exposed to inappropriate online content. Choose from 20+ predefined, age-specific website categories to block, 

or add individual sites to your blocklist. Set a password to protect against modification of settings, or unauthorized product uninstallation.

For Business and Enterprise Solutions

ESET Cloud Office 365 security features

Provides advanced protection for Microsoft 365 applications against malware, 

spam or phishing attacks with ultimate zero-day threat defense and an easy-to-use cloud management console.

Antispam

Now using an enhanced, award-winning engine with improved performance, this essential component filters all 

spam emails and keeps user mailboxes free of unsolicited or undesired messages.

Anti-Phishing

Prevents users from accessing web pages that are known to be phishing sites. Email messages can contain links that 

lead to phishing webpages.

Anti-Malware

Scans all incoming emails and attachments as well as all new and changed files. This helps keep each user’s mailbox free 

of malware and prevents the spread of malware through cloud storage across multiple devices.

Cloud sandbox analysis (NEW Feature)

Proactive threat defense against new, never-before-seen type of threats. Utilizes advanced adaptive scanning, cutting-edge machine 

learning, cloud sandboxing and in-depth behavioral analysis.

Automatic protection

With this option enabled, admins can be sure that new users created within the Microsoft 365 tenant will be automatically protected 

without the need to go to the console to add them separately.

Quarantine manager

An admin can inspect objects in this storage section and decide to delete or release them. This feature offers simple management of 

emails and files that have been quarantined by our security product. 

Arcserve & SOPHOS

Arcserve, LLC, the world’s most experienced data protection provider, today announced a global alliance with Sophos, a leader in network and endpoint security, to provide organizations with dedicated protction for backed up data against cyberthreats. Through this collaboration, organizations can now employ the only market solution that integrates anti-ransomware and other threat prevention technologies, such as deep learning AI for both known and unknown malware, and award-winning disaster recovery and high availability capabilities for prevention against data loss. Together, the new solution delivers a multi-layered approach to prevent, protect, and immunize backup data from cyberattacks.

Users store thousands of critical files on OneDrive to access them anytime, from anywhere. But, deleting a user account means their personal SharePoint site and OneDrive accounts are gone for good, too.

Eliminate the risk of losing critical business data with complete OneDrive backup.

• Secure Your Office 365 data from any cybersecurity threat with Sophos Intercept X Advanced technology
• Back up all or select OneDrive accounts
• Quickly recover files, folders or entire accounts
• Store backups on-premises and in cloud storage
• Reduce storage capacity with hyper-efficient global deduplication
• Copy backups to tape devices, tape libraries, and cloud locations, including the Arcserve Cloud, Amazon S3 and Azure Blob Storage

Microsoft offers Office 365 backup under a shared responsibility model, meaning they maintain platform uptime but it’s the responsibility of the user to prevent data loss.

And, while some businesses rely on native Microsoft Office 365 backup tools, doing so puts you at risk of data loss from human error, intentional deletion, external security threats, and programmatic issues.

Gain control and work worry-free with comprehensive protection for Exchange Online, SharePoint Online and OneDrive for Business as well as other physical, virtual and cloud workloads.

Antenna Grounding Kit

Outdoor Antenna Installation Tips

Looking for more guidance or want to educate yourself before cutting the cord? Here are some tips tailored to safely installing your outdoor TV antenna.

Please note: Every time you move or reconnect your antenna, you must scan for channels on your television. Consult your television owner's manual for more precise guidelines. We include Quick Start guides with all our TV antennas and also provide them here on our website for free.

Installation tips:

1. Before installing an antenna permanently on a roof or in your attic, test reception in that area and other locations prior to installation. To perform a test, connect the coaxial cable from the antenna to your TV. Then, place your antenna in the desired location. Turn on your TV using your TV and, using your remote, complete a channel scan. Once complete, flip through your TV channels and watch for signal interruptions. Make sure your antenna is installed where you get the best signal and the highest number of available channels.
2. Higher is always better. Mount the antenna on your roof or in the attic for optimal performance. These locations are more likely to experience fewer obstacles which cause signal interference between the antenna and broadcast towers.
3. Face the front of the antenna toward the broadcast towers. Even multi-directional antennas require this to achieve the best possible reception. Don't know where your towers are? Visit our transmitter locator or download our free Antenna Point app. 
4. Check your outdoor antenna regularly for secure coaxial cable connections and signs of corrosion. Sometimes debris or humidity can interfere with reception. Where possible, cover all connections and use waterproof sealant when installing an antenna mast. (See our included sealing pads for reference.)
5. Installing your antenna near power lines is dangerous. The antenna must be at least 20 ft. (6 meters) away from all power lines. If any part of the antenna or mast assembly comes into contact with a power line, call your local power company. Do not remove it yourself.

Note: Unfortunately, sometimes antennas are returned to us in perfect working order but were returned due to faulty installation techniques. Continue reading for troubleshooting tips.

Troubleshooting tips:

Spotty reception with accessories:

1. For the best reception, make sure the coaxial cable is the correct length for your installation needs. Similar to getting your antenna up high, terminating your coaxial cable at the right length will provide better reception to your television. 
2. If you are using a splitter, diplexer, or your cable run must be longer than 100 ft., consider using a preamplifier to boost weak signals. 

Spotty reception:

1. Reflected signals are also called "multipath interference". For those living close to broadcast towers, signal loss can occur when strong signals bounce off nearby buildings and other surfaces in the area. Aim your antenna in different directions, even sometimes away from the towers, and scan for channels. If this doesn't improve your reception, your installation may require an attenuator.
   
2. Do not install your antenna near metallic objects or reflective surfaces, as this could also cause signal interference.
3. Since the switch in 2007 from analog to digital signals, receiving TV signal is "all or nothing". You won't see "fuzz" or "snow" on your TV screen if the signal is weak or there is no signal. When a digital signal is received, it will display crystal-clear on your TV. If the signal is interrupted, your TV screen will be blank.

Combining multiple antennas

When combining multiple antennas on the same mast, keep at least 4 to 6 feet of vertical separation between the two antennas to prevent interference. If you want to combine signals from a UHF antenna with a VHF antenna so there is only one down-lead going into your house, use our UHF/VHF signal combiner with a channel filter for each antenna, designed not to pick up out-of-phase signals through the other antenna. For the best results, use equal lengths of coaxial cable from the output of each antenna when connecting to the UHF/VHF combiner.

Optional grounding information

For outdoor TV antenna installations, grounding the coaxial cable will protect your equipment from voltage surges created by nearby lightning strikes but will not protect from a direct strike. Check your local electrical codes to make sure your installation is in compliance. We recommend calling a professional electrician to advise or install your antenna. We have an educational page with suggestions for grounding your antenna.

Safety precautions:

If you are installing an antenna on the roof, assemble the antenna on the ground. Installing an antenna on windy days can be especially dangerous and even slight winds create strong resistance when attempting to set up an antenna or mast. 

Antennas that are improperly installed or mounted on inadequate structures are very susceptible to wind and weather damage. This damage could become life-threatening. The owner and installer assume full responsibility for the installation and verification that it is structurally sound to support all loads (weight, wind, ice, etc.) and is properly sealed against the elements and leaks.

Antennas Direct®, Inc. is not responsible or liable for any damage or injury resulting from antenna installations or by an antenna system failure due to any unknown variable applications.