RF Cafe Software
About RF Cafe
1996 - 2022
BSEE - KB3UON
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...
All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.
My Hobby Website:
Try Using SEARCH
to Find What You Need.
There are 1,000s of Pages Indexed on RF Cafe !
Anatech Electronics, a manufacturer of RF and microwave filters, has published its August 2015 newsletter. As always, it includes both company news and some tidbits about relevant industry happenings. This month, along with presenting some relevant industry news tidbits, Sam Benzacar discusses the importance of assuring high integrity RF cable and connector installation. Being a major manufacturer of connectorized filters, Anatech Electronics' products rely on proper interconnections to help guarantee specified performance. Filter responses are dependent upon the impedances of the input and output ports being very close to design-for values - typically 50+j0 Ω or 75+j0 Ω. Anything else will result in a curve that deviates from the shape obtained when tuning into a calibrated network analyze; the greater the impedance, the greater the deviation from 'ideal.'
FM Radio Coming to Smartphones
In what seems like an announcement that ought to have been issued a long time ago, T-Mobile and Sprint are incorporating over-the-air FM radio chipsets in their Android phones, according to Fierce Wireless. Sprint added it in 2013. Verizon had comment.
Wi-Fi For Surveillance
According to researchers at University College London (UCL), they have found a way to allow Wi-Fi signals to penetrate walls using Doppler shifts. The system compares the signals from a reference channel and a surveillance channel to monitor Doppler shift. It can work with 802.11 b, g, n and ac standards, GSM, and LTE. Unlike radar used for this purpose, the UCL design is a passive one-way system (not using signal reflections) that make it undetectable providing security for military and law enforcement use. MIT is also in the game, developing Wi-Vi, which device uses active radar, while another group uses particle filters to analyze small shifts in frequency and uses Sequential Importance Resampling (SIR) filters for greater accuracy.
Farmer Takes Broadband Into His Own Hands
Having become fed up with pitifully-slow Internet access on his Salisbury Plain (UK) form, farmer Richard Guy Salisbury Plain has homebrewed his own solution, according to the Daily Mail. As his LTE service was a lot faster what he got in his home (1 Mb/s), he built a wooden mast to which he attached a solar-powered LTE adapter, put it in a waterproof toolbox, and connected the signal to his house with a fiber optic cable. He now gets a blazing 69-Mb/s download speed. Of course, Guy also has IT experience which certainly helped
A Drone To Record Your Wedding
Looking a lot like Uber, Droners.io has launched a business Droners.io that connects people local, professional drone pilots to film your wedding, real estate, surf session, and whatever else you'd like. Pilot positions are available. You pay the pilot by project or per hour, depending on how you negotiate the deal. Once the pilot is done, you get an invoice that have a week to review. After that you use Droners secure payment platform with a debit or credit card.
Charlotte Pushes for Doppler Weather Radar
The Charlotte, North Carolina area is one of the few places in the U.S. that the National Weather Service Doppler Radar system doesn't cover, so Senator Richard Burr and Congressman Robert Pittenger are bringing the Metropolitan Weather Hazard Protection Act to Washington. If passed, the new law would require all cities of 700,000 people or more to have direct coverage of a Doppler radar. The nearest systems are in Raleigh, Blacksburg, Virginia, and Grier, South Carolina, but they don't fully cover western North Carolina. Burr says the new radar would cost $15 million and would include federal funding.
DoD To Scale Up Drone Flights
The Pentagon plans to expand the number of daily drone flights by 50% over the next 4 yr., according to the Wall Street Journal, in areas such as Ukraine, Iraq, Syria, the South China Sea, and North Africa, the first increase since 2011. Although the Air Force conducts most flights including those for the CIA, the new plan will also use Army and Special Operations Command assets, as well as government contractors. Daily flights would increase from 61 to perhaps 90 by 2019.
By Sam Benzacar
As it pertains to RF and microwave cables and connectors, Rodney Dangerfield got it right: "they don't get no respect". In fact, they're some of the most overlooked components in every system, which often turns out to be a mistake especially but not exclusively in systems that will be operated in hostile environments. They're crushed by everything from boots to trucks, bent far beyond their maximum bend radius, and subject to a remarkable number of abuses that even the high-quality cable could never endure.
Let's look at cable integrity, for example. The outer conductor or shield has the job of minimizing loss, keeping the signal from radiating along its length potentially causing interference, and ensuring performance by maintaining a fixed distance between the center conductor, dielectric, and outer conductor. Cable manufacturers take great pains to maintain very high tolerances between these components as together they determine the cable's performance.
However, when they're kinked, bent too far, or crushed, this symmetry is disrupted, causing discontinuities at various places along their length, increasing impedance mismatch (reflected power), hot spots when they are handling high RF power levels, and in general reducing receive or transmit performance. In the transmit path, severe impedance mismatch dramatically reduces RF output leaving the cable's far end and can destroy the RF power transistors in the amplifier. In the receive path, signal strength will be dramatically reduced. Abuse can also reduce shielding effectiveness causing the signal to radiate along its length. When radios are in close proximity and there are tens of hundreds of feet of cable in a small space (in a base station, for example) it's a breeding ground for interference.
Another of the many potential problems you can encounter is simply specifying the wrong type of cable for its intended application. Shipboard installations in salt water are a classic case as they are often continuously exposed to salt spray, which has a way of finding its way into places that seem impenetrable. The result is corrosion that can result in reduced cable (and connector) life, increased Passive Intermodulation Distortion (PIM), and sometimes outright failure. As there is generally no practical way to completely avoid exposure to salt spray, cables and especially connectors must be clearly identified as being satisfactory for marine use – and why. When they are exposed to aggressive chemical the cables must be made to (and advertised as) resistant to it.
Connectors suffer the same fate, as their components are equally subject to abuse from ham-handed installation (and sometimes reinstallation) when they can be overtightened, their center conductors bent, or just screwed on improperly. It's essential to make sure that whomever is doing the installation recognize that this isn't like plugging in a 120-V power connector – these are precision components.
The necessity for this increases with frequency, as high-frequency connectors are small and very delicate. In hostile environments, connectors can suffer even greater potential damage than cables as most of their components are partially or fully exposed and susceptible to contamination from whatever environmental hazards are present in the environment, from salt spray to salt or fresh water and chemicals.
So when you're specifying RF and microwave cables and connectors, please contact us before you start as we can steer you to the proper cable and connector combination based on their operating environment. You can reach us at (973) 772-4242 or by email at email@example.com. You can also view all our standard and custom products by clicking here.
About Anatech Electronics
Anatech Electronics, Inc. (AEI) specializes in the design and manufacture of standard and custom RF and microwave filters and other passive components and subsystems employed in commercial, industrial, and aerospace and applications. Products are available from an operating frequency range of 10 kHz to 30 GHz and include cavity, ceramic, crystal, LC, and surface acoustic wave (SAW), as well as power combiners/dividers, duplexers and diplexers, directional couplers, terminations, attenuators, circulators, EMI filters, and lightning arrestors. The company's custom products and capabilities are available at www.anatechelectronics.com and standard products are available for purchase at the Anatech Electronics integrated Web store https://www.anatechelectronics.com/index.php/webstore
Anatech Electronics, Inc.
70 Outwater Lane
Garfield, NJ 07026
Posted August 23, 2015