Category: Communications & Receivers

Letter Re: Internet Privacy Practices For Preppers

Dear James, I have accounts on Gmail, Yahoo mail, Facebook and LinkedIn. Like many people, I have found it convenient to stay logged in to my online accounts with my personal computer. While on LinkedIn a few weeks ago, I was “recommended” a business associate who I had not been in contact with for nearly 10 years. This alarmed me. How did LinkedIn make this association? So, I looked back through my Yahoo mail and found that I had corresponded with this business associate in 2001, via Yahoo mail. Several weeks later, I was recommended a “friend” on Facebook who …


Letter Re: Nationwide EAS Test Failure

Mr Rawles: I had to send along the link to the news article about the failure of the nationwide test of the Emergency Alert System (EAS) with the observation that I would have bet this wasn’t going to work.   I say that as a retired Air Force avionics technician whose job was maintaining and flying as a crew member on the EC-135A, C, G, H, and L model Airborne Command Post Aircraft.  As well as in an advisory capacity for five years when the job was passed over to the Navy E6B in 1998.  Even on our best days with everyone doing …


Letter Re: Radio Communication and Antennas

All radios need an antenna and the type of antenna chosen will determine important performance characteristics. Let us start with a radio most people are familiar with. The citizens band radio is typically supplied with some form of mobile vertical whip style antenna. This antenna is usually mounted vertically on the vehicle and it radiates radio frequency energy with mostly vertical polarization. Most CB users have vertical antennas so they are most sensitive to similar signals having vertical polarization. If a person using CB radio wanted to make his signal heard by his comrades more and less by people outside …


Letter Re: Uses For Discarded Satellite Dishes at a Retreat

Hello Jim, and Readers: Recently I was looking for a way to record some long distance sounds, and thought of a solution for Listening post observation posts.  I discovered  an old Dish Network or Direct TV dish will work fine with a microphone mounted to it. Using a UHF or N type bulkhead RF connector mounted to the point where the old  antenna LNB was mounted I drilled a hole large enough on the front of the antenna mount with a step drill for the base of the  RF connector, and 1/8th holes for the flange mount of the connector, and mounted …


Simple Electronic Devices and Hacks for Every Day Preparations, by Pat in Oregon

Technology is a significant force multiplier in emergency situations.  There are several options I’ve found in my preparations to incorporate electronics into our everyday use and emergency preparations.  Hopefully these ideas will be of use and get others thinking about possibilities.  My goal in utilizing these ‘gadgets’ is to increase availability of resource while decreasing maintenance and effort – all at low cost if possible.  I’d like to share a few of the low-cost options that are simplest to try that we’ve adopted in our preps. I’m an engineer and realize most of the tools I use won’t be appreciated …


Letter Re: Long term Survival Electronics Storage, Tin Whiskering and RoHS Compliance

James, Your readers that store modern electronics long term should be aware of this. There is a problem with all modern electronics that are RoHS compliant. RoHS stands for Reduction of Hazardous Substances. One of its requirements mandates the use of lead free solder in all consumer electronics. This started in Europe and subsequently adopted here in order for the US to sell products outside this country. There is a physical process know as tin whiskering, where by tin will grow microscopic metallic whiskers. See NASA’s web site for extensive research and information. Please do your research on this and …


Letter Re: Is Your Flash Memory Data Really Erased?

Hello James: Take a look at Deb Shindler’s blog post linking to a PDF download about reliably erasing data from SSD drives.   Here is just one sentence from the second paragraph of the PDF that really struck me.  “Third, none of the existing hard drive-oriented techniques for individual file sanitization are effective on SSDs.”  Thanks for all you do. – Joe K.



Letter Re: CONEX Shipping Containers as Faraday Enclosures?

Captain Rawles,  As most of your readers would say, we thank you for your ministry.  My question is weather a 40′ Continental Express (CONEX) shipping containers would work as a huge Faraday cage, and thus we would be able to store most of our sensitive electronics, such as communications gear, battery chargers, e cetera.   Thank you again, – R.L.S. JWR Replies: There are a few problems with that concept: 1.) The vast majority of CONEXes have wooden floors. Wood is fairly transparent to radio frequency (RF) waves, including electromagnetic pulse (EMP). A metal Faraday enclosure needs to be an integral box. …


The Five Steps of OPSEC Assessment by Stone of Scone

Operational Security (OPSEC) which is the evaluation and control of any critical information that could be used against you by an adversary. The result of good OPSEC is the elimination or withholding of the most damaging information that your adversary has the ability to gather and understand how to use against you. OPSEC happens everyday. When you go on vacation and hold your mail and newspaper delivery, and use timers to turn your radio and lights on and off to make it appear that you are home, you are practicing good OPSEC. Here is a another example of OPSEC. A …


Three Letters Re: COMSEC: One Time Pad Generation

Sir: I agree with the response posted, and your reply. While older versions of Perl used relatively poor pseudo-random number seeds, the original author’s use of a time (at runtime) index as a pseudo random number (PRN) generator seed is a reasonably “secure” method of generating a series of PRNs. That was the first thing I looked for in his code, and such a method would be secure given the caveats you suggest. (That is, it won’t be up against true high-power cryptanalysis). If applied with random letters instead of words as suggested, (like a “real” one time pad), it …


Letter Re: COMSEC: One Time Pad Generation

Hey Jim: I am a little concerned about yesterday evening’s post by B.R. regarding the generation of one-time pads. It claims to generate a “pad” using a random selection of dictionary words. A properly generated one-time pad requires a truly random selection of letters; it is only as strong as the source of entropy. Using a dictionary of English language words, acronyms, etc. does not seem to be very wise. Additionally, while I am not terribly familiar with Perl, I know that a lot of languages have built-in “random” functions that are not as random as one might hope for; …


COMSEC: One Time Pad Generation, by B.R.

While re-reading the ‘Radio Ranch’ chapter in JWR’s novel “Patriots“, I started thinking about the Book Code method versus a One-Time Pad. I went through the books on my shelf, and noticed the lack of duplicate books; the number of ‘common’ books; and how many of my books I figured would be in the Uncle Sam’s cracked book repository. At that point I thought I’d be SOL when trying to setup a secure method of communication. Being an ex-Army Infantry turned computer geek and prepper, I figured it would be much easier to write some code to generate pages of …


Letter Re: Antenna Launching Alternatives

CPT Rawles:s I know this is a very obscure topic, but having been a communication guy on a Special Forces A Team for many years and a ham radio operator, I know a couple things about wire antennas in trees. I’ve tried them all, slingshots, bow and arrow, lead weight, one-quart canteens et cetera. The problem is getting the right weight to mass ratio – otherwise you either can’t get the rope up high enough, it gets caught up in the branches or wraps around the branch you are throwing at. The single best object I have found is an …


Two Letters Re: Blending In–Unremarkable and Invisible Architecture

Sir, Happy Independence Day to you and your family. Concerning underground tanks for fuel storage, most states require both lining systems and cathodic protection to prevent leakage into the ground and or ground water. I fully agree with the defensive sense, being a veteran of the US Army and most of my time serving in the Infantry, having prepared many a defensive position.   As such for OPSEC, finding a discreet contractor may present a challenge, and of course the local county may get interested, Hopefully not too much. – Grog   JWR Replies: Cathodic zinc anodes (commonly called “sacrificial …