Free Republic

Sorry for another post but I'm praying that Tehran has made its point and that is it for now. They have bombarded Israel but have failed to really hurt or harm them. The BBC even show bars are open in Jerusalem. Do not be alarmed. Do not panic on here. I'm hoping that this does not escalate despite the unprecedented nature of the attack. How do Freepers see this playing out?

Patch antennas are regularly used in ATVs, beacons, MIMO, wi-fi applications, AMSAT, GPS, repeaters, wireless systems and dish feeds. But what are the pros and cons of using them?

This talk should be of interest to anyone interested in building their own Yagi antennas for the VHF and UHF bands. The talk lasts for about 38 minutes with a short 10 minute Q&A session after it. WA5VJB also has his own website which has antennas and equipment for the microwave bands here... https://www.wa5vjb.com/index.html Posted by John, EI7GL at Thursday, February 18, 2021

Those of us who are either in-house or independent EMC consultants can benefit greatly by assembling our own EMI troubleshooting kit. I’ve depended on my own kit for several years and it has proven not only valuable, but depicts a sense of professionalism in dealing with your own product development engineers, their managers, or your clients, as the case may be. Mine is designed around a Pelican 1514 roller case (http://www.pelican.com) that includes a padded divider, so it is easy to transport to the area needed. You’ll also want to order the optional lid organizer, model 1519, for carrying extra...

I received a log periodic antenna designed by ham radio operator WA5VJB from Kent Electronics. They are rated from 2 to 11 GHz, so this model will cover several of the ham bands. These antennas are made on PCB's and are ideal for use in the amateur microwave bands as compromise dish feeds. In this video I do a test of such a feed versus my patch antenna on the 3.4 GHz band. https://www.wa5vjb.com/products1.html I mounted one in place of the original dipole feed on a 2.4 GHz (13cm) gridpack at the same focal point. Whilst gain will be down...

So many satellites are moving and sitting over our heads, and the numbers are ever increasing. Using low cost software defined radio (SDR) and low cost DIY antennas you can make from materials at your local hardware store or garage, a world of fun can be explored. This is a beginners guide on how to get up and running. Exploring which projects to tackle first, from weather satellites, data over Inmarsat and Iridium, to listening to amateur radio and cube satellites. Learn about some hardware you can make or scout for online and use at home. A quick tour of...

Care and feeding of Software Defined Radios We will cover the various kinds of antennas available to optimized your SDR radio for different types of spectrum monitoring. We will also explain why RF filters are necessary on most SDR's and when Low Noise Amplifiers help, and when Low Noise Amplifiers hurt reception.

The anti-cancer device, Cytotron, developed by Bangalore-based Rajah Vijay Kumar received a “breakthrough” designation from the U.S. FDA’s Center for Devices and Radiological Health for the treatment of liver, pancreatic and breast cancers. Having this designation means that there is evidence that the drug or therapy that treats a serious condition, in this case, a device, demonstrates “substantial improvement on a clinically significant endpoint(s) over available therapies.” With it, the review and development of the treatment will be expedited so that it will be available as soon as it can be concluded that the benefits justify the risks, considering the...

North Ridge Church's awesome sound system set up for only a few hundred dollars while putting out professional performances. DIY Wireless Microphone RF Distribution https://www.youtube.com/watch?v=SH3VKHcwDj0

This cheap little project for signal detection on Earth was to find RF sources interfering with SETI signal detection. http://www.seti.net/notebook/volume-8/chap57/chap57.php

BARABOO — Residents in this small southern Wisconsin city have two choices when it comes to the brave new world of the Smart Grid: Go along with new “smart” meters for public utilities or get along without water, gas or electricity. Most residents don’t make a fuss and let the utilities install the new smart meters, which are supposed to provide utility customers and taxpayers with savings from real-time data usage and less manpower needed to read traditional analog meters. Some residents, however, including 81-year-old Audrey Parker, say the smart meters are an invasion of privacy, and they believe the...

Lately, there seems to be a lot of conflict on the religion forum. Much of this has been between Catholics, Protestants, and Orthodox. To show that we are all united as Christians and to reduce animosity, I hope we can all agree to one of 4 following statements: 1) I am Catholic. I love Orthodox and Protestant Christians. I consider Orthodox Christians and Protestants to definitely be Christian. All Christians need to work together to defeat our common enemies-- specifically Islam, liberal postmodernism, and totalitarian communism. 2) I am Protestant. I love Orthodox and Catholic Christians. I consider Orthodox Christians...

This is a reader video found on Macrumors forums illustrating something weird. When the guy holds the iPhone in his hands, touching the outside antenna band in two places, he drops reception. Placing the phone down gets him 4 bars. We're not sure if he's doing something particularly weird, like holding the metal antenna in such a way that it's shorting out. But it is strange. Or, it could be just a bug in the software, showing no bars and no reception even when you do have reception. But, he does hold the phone with the glass, and it doesn't...

America’s 21 B-2A Spirit stealth bombers have been leaders in stealth technology and weapon support arrangements. Now, they’re a leader in a less desirable category. DTI’s Bill Sweetman reports that during a 2008 bandwidth auction, the U.S. Federal Communications Commission inadvertently sold the operating frequency band of the B-2 bomber’s Raytheon AN/APQ-181 radar to an obscure firm headed by a Russian-educated citizen of Mali. Installing new radar arrays on the 20 surviving jets will reportedly cost “well over $1 billion.” Sweetman notes that this is just one side effect of spectrum allocation problems, and greater civilian appetites for its use....

U.S. Sen. Bob Casey lowered a lighted match to a test tube filled with saltwater. An orange flame instantly erupted from the mouth of the tube. "I'm two for two at igniting the saltwater," Casey said with a smile. Casey spent part of Wednesday afternoon at Industrial Sales and Manufacturing Inc., watching a demonstration of Millcreek Township inventor John Kanzius' radio-frequency device. He is the latest on the list of high-ranking public officials who have trekked to the yellow-brick laboratory on West 15th Street to see the device. Gov. Ed Rendell and U.S. Rep. Phil English, of Erie, R-3rd Dist.,...

Public release date: 14-Sep-2007 [ Print Article | E-mail Article | Close Window ] Contact: Laura Ostlaura.ost@nist.gov 303-497-4880National Institute of Standards and Technology (NIST) 'Radio wave cooling' offers new twist on laser cooling NIST physicists used radio waves to cool this silicon micro-cantilever, the narrow orange strip across the middle of this colorized micrograph. The cantilever, created by ion etching through a silicon... Click here for more information. Visible and ultraviolet laser light has been used for years to cool trapped atoms—and more recently larger objects—by reducing the extent of their thermal motion. Now, applying a different form of...

Susan Moses Created: 5/15/2007 2:59:08 PM Updated:5/16/2007 6:11:13 AM SANIBEL ISLAND, FL -- A Florida retiree battling cancer himself has discovered a possible method of killing cancerous cells with radio waves. If it works, it could be the "Holy Grail" of cancer treatments. His is the great American story. A broadcast engineer, who shrewdly evolves into the owner of several TV and radio stations, sells them for a bundle and retires early to picturesque Sanibel Island. But Easter 2002, began an unexpected chapter in the story of John Kanzius, a year and-a-half after he retired. He was diagnosed with a...

Wireless Internet networks are cropping up in coffee shops, campuses and even entire cities, and though you can't see or feel them, one man thinks they are dangerous. Frederick Gilbert, president of Lakehead University in Ontario, Canada, is concerned about the radio waves that wireless systems emit and has vetoed the idea of constructing a campuswide wireless Internet network. Like cell phones, radios and TV broadcasts, wireless networks use equipment that generate electromagnetic fields, which Gilbert said are hazardous. Penn currently offers wireless Internet access in several buildings and plans to install the service in all college houses by this...

FREDERICK, Md. - A new radio system at Fort Detrick will improve communication with the Pentagon. The downside: some people may have to open their garage doors the old-fashioned way. The Land Mobile Radio system will allow Fort Detrick and 10 other Army installations in the Washington region to communicate with the Pentagon and civilian emergency personnel by hand-held radios. In a suburban sacrifice to emergency preparedness, Frederick residents could experience a rash of dead door openers in coming days, as the Army's Fort Detrick begins using a new radio system linking local and federal government emergency personnel. The new...

'Muslim women don't have a problem with the fact that their husbands have a few other wives," declared the Iranian ayatollah with great conviction. Sitting across the conference table from him, in the magnificent 17th-century Villa Serbelloni on Lake Como in Italy, I disagreed. My conversations over the years with Muslim women colleagues had given me a quite different picture. "I would suggest that you don't really know how women feel since you're a man. I'm a woman, and I can tell you that women do not want to be one of several wives." While ordinarily this kind of challenge...