Anatech Electronics Newsletter - July 2014

What's New

Powerline EMF Exposure Back in the News

Power-frequency magnetic fields can promote brain tumors, according to the largest epidemiological study of its kind ever undertaken, raising once again the idea that ELF radiation from power lines is likely to be a cancer promoters rather than a cause. This hypothesis gained support a generation ago but has lost currency in recent years. The results, published by the journal Cancer Epidemiology, Biomarkers & Prevention, come from INTEROCC, an international project with seven participating countries designed to investigate occupational health risks from chemicals and EMF.  The study found that people exposed to elevated EMF exposure at work during the five years prior to diagnosis had significantly higher rates of glioma compared to those who were least exposed during that time on the job. The greater the exposure, the greater the tumor risk. Those who were most highly exposed had approximately 67% more tumors.

Report: Microwave Device Market to be $1.2 billion by 2019

According to a new research report "Microwave Devices Market by MarketsandMarkets, the global microwave device market is expected grow 3.0%, and reach $1.2 billion by 2019. The increase in the number of navigation radars used by UAVs and the “Internet of Everything” are the driving factors, according to the report.

LTE TV: It Was Inevitable

Ericcson believes that LTE broadcast will soon make its way to consumers for personalized mobile TV, according to the company’s master researcher, Joerg Huschke. Based upon evolved Multimedia Broadcast Multicast Service (eMBMS) and available commercially beginning with 3GPP Release 9, LTE broadcast (also called LTE Multicast) would be a single-frequency network broadcast mode that can send the same content to mass audiences within a specific area. The latest Ericsson Mobility Report forecasts that annual video traffic in mobile networks will grow 55% by 2019 as terrestrial TV continues to lose market share to cable and fixed broadband. AT&T and Verizon Wireless are rapidly exploring the potential of LTE Broadcast

GM First With In-Vehicle LTE Hotspot

A General Motors/AT&T partnership is about to bring 4G connectivity to Chevrolet cars. With massive fanfare, the company rolled out its in-vehicle 4G LTE promotion with in Philadelphia during the city’s 4th of July fireworks and outdoor concert. It’s OnStar subsidiary is providing the connection for new vehicles with a trial duration of 3 Gbytes or three months. The 2015 Chevrolet is first followed by more than 30 vehicles by Buick, Cadillac, Chevrolet and GMC. OnStar Directions & Connections or Safe & Sound plan subscribers can get 200 Mbytes of data for an additional of $5 a month, enough (says AT&T) for 6.5 hr. of music streaming, 13 hr, of Web surfing, or 10,000 emails with no attachments. Charges for other OnStar customers begin at $10 per month. Up to seven devices in the vehicle can connect to this mobile Wi-Fi hotspot whether inside or around the car.

Researchers Switch Woman's Consciousness On and Off

Scientists at George Washington University may have accidentally discovered a way to switch consciousness off and on, according to CBS News. Working with a 54-year-old epileptic woman, they were probing different regions of her brain using electrical signals sent to implanted electrodes in an attempt to identify the source of her seizures. When they stimulated a thin layer of neurons attached to the neocortex found on both sides of the brain, the woman appeared to lose consciousness, though she did not experience a seizure. The woman continued to speak and snap her fingers at the researchers’ request, but gradually tapering off after she lost consciousness. Once the electrodes were shut off the woman regained consciousness and did not remember what had happened. According to CBS, the researchers say that their discovery may help provide a new way to treat epilepsy, comas, schizophrenia or other disorders.

Curing Interference: Never Too Late

By Sam Benzacar

Whether you’re a circuit designer, base station installer, or anyone in between, the ideal time to consider interference (and mitigate it using RF and microwave filters) is at the earliest possible time – either during the design process or before the system is installed in the field.   Unfortunately, that’s often not what happens. The result is either design rework, a truck roll and tower climb to install a filter, or some other frustrating, time-consuming--and costly--experience. I can say with certainty that solving interference problems in completed designs and in deployed systems is hands down our most frequent customer request.

Filter manufacturers aren’t alone in this scenario: Connector and cable assembly vendors face the same issues, as both of these seemingly mundane components play major roles in determining overall performance especially at higher frequencies, when phase and amplitude stability are concerns, and most recently when Passive Intermodulation Distortion (PIM) must be kept to levels so low that only a few years ago they were beyond the range of the few instruments available to measure it.

Obviously, there are many scenarios in which it’s not possible to know whether or not interference will be an issue at “ideal” times. Co-location of multiple services on towers, for example, has made this an issue at thousands of sites serving carrier wireless and public safety. Towers that once served one or two services are now serving four or five, and predicting if and when new services are added is typically impossible.

Fortunately, it’s rarely if ever necessary to through in the towel, as filters can almost always reduce in-band interference or even eliminate it entirely, even when the interfering signals are very strong and very close to your operating frequencies. Cavity and LC bandpass, lowpass, highpass, and notch filters can be designed with extremely sharp skirts and very low insertion loss and yes, extremely low levels of PIM as well.

They can also be housed in enclosures that allow them to meet stringent IP-68 requirements so they can withstand many years of reliable service in hostile environmental conditions at the top of a tower, from dust to rain and moisture and wide temperature extremes, exposure to corrosives, and other potentially damaging conditions.

Of course, it would be ideal if the potential impact of interference could always be predicted and compensated for “up front”, but this is not an ideal world and no one is perfect or clairvoyant. So when you encounter a situation like any of these, please call Anatech Electronics because after nearly 25 years of solving such problems, we can solve yours as well.

Call us at (973) 772-4242 or send us an email to filters@anatechelectronics.com.

We can help.

Product Highlights

Notch/Bandpass Duplexer for GSM Downlink

AEI notch/bandpass duplexer has a frequency range of 869 MHz and 894 MHz. It is used for GSM downlink and is available in DIN (7/16) Connector.

450 MHz Block D Duplexer for Public Safety

AEI public safety duplexer has a band frequencies of 411MHz to 415 MHz and 421 MHz to 425 MHz. It has a low insertion loss and a bandwidth of under 4 MHz.

Amateur Radio Community; A Resurgence

A while back, this newsletter featured an article called “A Ham’s Lament” that bemoaned the fact that young people today take it for granted that communicating with anyone is simple and that this was affecting the health of amateur radio. It also stated that amateur radio overall is not growing, to which the public relations department of the ARRL took great umbrage, as in fact it was, although at the time of the article not by much. So the ARRL was right nevertheless too few young people, even those with genuine interest in science, are availing themselves of what amateur radio can give them. And there is indeed plenty that this “hobby” has to offer, more in fact than at any time in its history.

While the ability to build a transceiver like those available from Icom, Kenwood, or Ten-Tec, is beyond the means of any hobbyist, antennas, keyers, many associated devices and even linear amplifiers, are not. In addition, the capabilities afforded by digital technology continue to expand the features and performance available from commercial transceivers, allowing hams today to explore more parts of the spectrum using more modulation techniques, all within a single “box” than anyone could have imagined many years ago.

So what is the health of amateur radio today? The ARRL released statistics in January that show the amateur community growing like a weed after plummeting between 2004 and 2007 and rising dramatically after the FCC did away with the need to pass the code test. At the end of last year there were 717,201 licensed amateurs in the FCC’s Universal Licensing System (ULS), a record, and up from 709,575 a year earlier. According to the ARRL, amateur radio applications slowed somewhat to 141,943 from their peak of 176,826 in 2007 when the FCC dropped the code test. Club station licenses are also at an all-time high at 11,363 and the number of new club station licensees roses by 7% percent over 2012 (28,886 versus 27,082).

There are 349,163 Technician licensees, 167,257 General class licensees, 133,191 Extra class licensees, and 54,293 Advanced licensees. Just over 13,000 Novices are still on record although the FCC no longer issues either Novice or Advanced licenses. Technicians grew 8.2% in 10 years with most of the growth after 2007 after falling to 338,334 in March 2000. General class licensees have grown by about 18% over the past 10 years. However, the most amazing statistic by far is that Extra class licensees have risen by an incredible 27%, which means that rather than resting on their laurels, hams have been improving their skills and knowledge. ARRL volunteer examiners served 34,896 exam applicants in 2013 up a bit from 32,866 in 2012.

So while there may not be as many RF and microwave engineers who got their start as hams, the amateur radio community overall is healthy, and that’s a very good thing.