Letter Re: Is Radio Direction Finding a Potential Threat for Survivalists?

Mr. Rawles:
Hey, I was just wondering what everyone with radios is planning in order to conceal the location of their transmissions from people who could potentially use the signal as a beacon to guide them right to your antenna. It might be fairly difficult to build a tracker, but I suspect there are pre-made devices to direction-find a fairly strong signal (e.g. ham radio). Thanks, – James D.

JWR Replies: The only people that have effective radio direction finding (“DF“) equipment and the requisite expertise to operate it are A.) The NSA and a few other government agencies such as the FCC–mainly for tracking down unlicensed pirate stations, and B.) ham radio operators themselves, who practice playing “fox and hound”. (Here is a sample of a site dedicated to the latter –quite a sport.) Hams tend to be very law-abiding folks. I can’t imagine many of them going renegade and turning into looters. However, I can foresee many looter gangs showing rudimentary SIGINT skills and using portable public service band (“police”) scanners. So it is wise to use low power and directional antennas. Never mention surnames, locations, lat/long, map coordinates, or street addresses “in the clear.” In my estimation, it is not likely that looter gangs would be sufficiently sophisticated to use DF gear. But never take anything for granted. It is conceivable that someone that worked in the SIGINT community could sell their services to a large looter gang, in a “slow slide situation. Be prudent and take the proper COMSEC measures. If and when the Schumer hits the fan, you should construct your own brevity codes and change your call signs and frequencies frequently. Oh, by the way, I describe radio intercept, radio direction finding, and COMSEC in considerable detail in some of the closing chapters of my novel “Patriots” , which recently went back into print. Among others, one of the methods that I describe in the novel is bouncing signals from a directional antenna off of large metal structures such as large barns or grain silos, to confuse DF operators. I also discuss HF transmissions, which have near vertical incidence when propagating in long distance skywave mode. It takes very sophisticated equipment to DF those signals. (As opposed to short distance groundwave HF signals, that can easily be DFed.)

One further note: We now live in the age of Bluetooth. If and when TSHTF, if you have a wireless network for your home computers, you should plan to turn the transmitter off and use it as a strictly “hard wire” Ethernet device. A clever looter might leave a laptop turned on in his vehicle, sensing when the vehicle passes an active wireless network. (Even if you keep blackout shutters up–making your house look like all of your neighbors that are without power–an active wireless network could mark your house as a lucrative target.) Ditto for cell phones and cordless telephones. Assuming that the phone circuits are still working during a period of lawlessness (not likely, but possible), be sure to switch to “land line only” for the duration.