Two Letters Re: New Scanner Technology — An Emerging Threat to COMSEC

Regarding the “signal stalker” technology: This type of thing has been available for years in the form of frequency counters. Perhaps the best known in the ham/scanner community is the Opto Electronics Scout series. These units let you scan for radio transmissions and will store the last detected frequencies in memory for later recall. This is a handy feature if you are visiting a race track, for instance and want to find out the frequencies in use while you tour the pit area.
They also sell a cable that will interface to various scanners, allowing you to immediately tune in to the detected frequency. Some models also decode the PL tones for you.
Keep in mind that these work best when you are in a “quiet” area, i.e. not too many commercial radios, cell phones, etc in use. They have a pretty short range in a noisy RF environment like a major city.
For enhanced COMSEC between locations, consider using low power and directional antennas. If you’re not radiating the energy in 360 degrees, there are a lot fewer places it can be intercepted from.
Cheers, – JN-EMT.

I agree with you that throbbing out high power Ham signals is not needed, but most ham kits I’ve seen allow down powering; there’s even a subset of the hobby that specializes in low power operation.
I am having the devil’s own time finding many MURS rigs. Still lots of CB out there, but MURS seems to have fallen out of favor with FRS/GMRS and the remaining CB users. Where are you finding your gear? Are there the same line of sight VHF troubles as with FRS? If so, how are you getting a good lightning proof antenna up? I’d have to have my nice radios burned out by EMP, or worse a simple thunderstorm. Regards, – Michael G

JWR Replies: One nice feature of many 2 meter handhelds is adjustable output power. I agree that it is best to use minimal power and directional antenna. If you suspect that someone might be trying to intercept and possibly conduct direction finding (DF), then use terrain masking. In my novel “Patriots”, I also describe a method for bouncing signals off of metallic structures, to confuse DFers.

Until recently, we had $49 MURS Radios as an advertiser on SurvivalBlog,. They sells Kenwood MURS hand-helds. They stopped advertising only because they are now nearly out of radios. (They bought them as trade-ins, in a big package deal.) Sadly, they are having trouble finding any more to sell

The range of the Kenwood MURS seems much better than FRS. By comparison, the FRS hand-held radios are pipsqueaks. For very short range communications (such as within a retreat perimeter), that might actually be a COMSEC advantage.) MURS hand-helds are still under 5 watts of effective radiated power (ERP), so they have fairly low probability of intercept (LPI.) beyond about 8 miles, in all but dead level terrain.

Our base station antenna here at the ranch is equipped with a good ground and a coaxial in-line surge protector. (A DLS “Surge Ender”, model SE-1), to provide at least modest lightning protection.