“Another topic that I would like to learn about: covert antennas (at home and on vehicles). I live in a subdivision that has nosy neighbors and a restrictive home owners association, so Ham antennas aren’t allowed. Are there relevant use cases for remote transceivers? If we don’t want to radiate from home, but our gear’s at home, how can we transmit without undue DF risk? ”
YT et al; I might be able to shed some first hand experience w covert suburban comms, as I currently live in a large HOA governed community outside a large southern city, and have to be very creative with my set ups. My comms plan revolves around the ability to listen and talk, locally, regionally, nationally and globally, in that precise order, which drives my selection of kit and antenna configurations. For listening I have a Uniden Home Patrol II digi scanner, a pc based sdr kit, running SigInt OS and my most recent addition is a Uniden SDS100 handheld scanner, and an analog Uniden Bearcat BC125AT w close call option. I also have a Kenwood TM-V71 UHV/VHF mobile under my desk, that has been modified to wider frequency usage to cover FRS/GMRS/MURS and other freqs, and an Alinco DX-SR8 HF rig. I pretty much all of my bands/services covered. We live in a 1700sf ranch, decent attic and normal trees lining the sidewalk in front our home, and across the street where there is some green space and large trees. That’s the easy part, the kit, now the hard part is antenna selection and placement, without getting onto the HOA hit list. For my vhf/uhv/scanning rx/tx, I chose the attic option. I have an Arrow J pole in the attic, mounted on a 1” 4ft wooden dowel, and use a flag pole mount to get it vertical, up to the peak of the roof and run feed line down into my home office, and to Kenwood. With this set up I can hit all the local repeaters and Mt. Mitchell, 151 air miles away at 6600ft elevation, the Beast of the East. I am able to simplex other stations 20-30 miles away, and more when I use my yagi. This solves my neighborhood/tactical/local and regional two way commo goal.
Now for scanning I have a Diamond Discone mounted to 1” wooden dowel, and same flag pole mounting hardware, with feed line into office, running into a 3-way S0-239 switch, so all I have to do is switch to sdr dongle or scanner on the fly. The D130J Super Discone Antenna is an ultra-wideband antenna covering amateur radio, commercial 2-way, cellular, air traffic control and various utility frequency bands. This antenna has great specs 25-1300Mhz and can be used on 2m, 70cm, and 6m as well.This allows me to rx on all the bands/freqs that I could ever want or need. What does all of the accomplish? None of my neighbors know I have this set up in the attic and what my capabilities are, and the HOA is none the wiser. Now, on to HF, a whole ‘nother animal to deal with. What’s my HF commo goal/plan? That question drives my set up, and should drive yours too.
First off, my main concern with respect to HF is to RX first, and TX secondly, and on in a regional basis, if I get national TX, great, but mainly within a 500 mile radius which gets all of the Southeast, out to Memphis, up to Detroitistan, and North of Philly, down to central Florida and the entire eastern seacoast for marine traffic. That’s pretty much all I care about. I can pull out my SW radio and pickup comms from the west coast or elsewhere if need be. Now, since that’s my goal, I need and antenna configuration to handle it, so I went NVIS using an end fed 148ft long wire antenna connected to an LDG 9:1 unun to my LDG Z-100 Plus Tuner and I get 10-160m coverage .Now, the unun is mounted to the outside of my front porch, support post, and the wire is 14g multi strand coated wire that is run from the unun to a tree at approx 20ft, then across the street to other trees where it is connected to anchor line, with a 5lb weight at the end, so it is suspended and has survived several wind and thunder storms. When I need to get on air, I simply run my feed line to the unun and fire up HF rig, tune up antenna and get on air. I have an outdoor electrical box with pvc piping from my office going thru wall into box, that manages my feed line. From a casual glance, nothing to see, as it looks like part of the cable/electrical accessories any home would have. A few people have noticed the wire, a couple have asked and I tell them its for shortwave reception and they move along. Most folks driving down the street, never know its there, it just disappears into the background.
I have also developed a tilt up temporary mast system using a 5gal bucket, some quickcrete, 2” pvc pipe and chain link fence 10ft top rail sections with a pvc t-bracket at top, and a carabiner to hold either a small end fed sloper or dipole, connected to ladder line or normal feed line. This can go up in minutes and is perfect between the homes at night, no one is the wiser and I have made, do make, QSO’s within my AO. That covers the fixed aspect of suburban comms, my suv covers the mobile aspect. It is set up for vhf/uhv comms with a Kenwood TM-V71, again modified, and wideband scanning using a Diamond Mobile Disconce Scanner antenna, have the handheld scanners to connect to discone, and my designated SigInt OS laptop as well. I can be on the move and communicate and if I bring my Yaseu FT-817 w tuner and simple di-pole, and some bank line and a fishing weight, I can have mobile HF comms, that is damn nearimpossible to DF. That said, if your concern is being DF’d then that should be part of your normal commo plan and Brushbeater covers that in great detail in his classes and online resources, that’s another post. I hope this provides you real world examples of how one can still communicate on the down low.
One thought on “Covert comms for the urban/suburban dweller, by RomeoFox”
A 9:1 unun is the secret weapon of HF…(2MM wire rope 23.83M long will give under 1.5:1 vswr on 20M to 6M –on 40M your tuner will take up the slack).
For VHF and UHF, if a yagi is too long, try a biquad. Easy to roll your own and tremendous gain.
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