Letter Re: Stuff Hitting the Fan – Part 3: Communications

Dear James,
I need to respond the the letter “Stuff Hitting the Fan – Part 3”, with regards to communications. I am a ham radio operator holding a Amateur Extra Class license, and have a little CB and shortwave experience.  As such, I want to make some corrections R.L.’s letter and offer some advice.

1. An adequate ham transceiver for the HF bands (160m to 10m), will also cover the non-ham bands as receiver. This includes all of the broadcast shortwave bands, and the AM broadcast bands in the United States.

This will not include US broadcast FM, or the police and fire frequencies, which are outside it’s frequency range (you would need a VHF transceiver for those bands). So if you get a HF ham transceiver such as the Yaesu 450D, you can save half your money by not buying a shortwave receiver too.

2. All shortwave broadcasts use the AM mode. None use single side band or CW. 
    
3. Shortwave broadcasts to the western US are pretty rare right now. On the eastern seaboard you can get Europe, but there aren’t many people targeting the US with shortwave because of the prevalence of the Internet. There are, however, some stations you can pick up in Nevada (for example) that are clear even though they are not targeted to the US.

These are: the Australian Broadcasting Company, Radio New Zealand, and China Radio International. Unfortunately, the Brits and the Germans are no longer broadcasting in English to the US. If you speak Spanish, there is a lot of shortwave activity coming out of Latin America. 

4. There is a cheap and legal way to make your CB base stations more effective. Use single side band (either lower or upper), and use a horizontal dipole antenna not far off the ground. This will cause your signal to go nearly straight up to the ionosphere, where will be reflected back down like water out of a shower head.  The advantage here is that your signal will get into places like  between building, gullies, valleys and behind mountains, where it would normally not be able to go. The receiving station should have their antenna set horizontally to receive this well. This sort of antenna usage is called NVIS for Near Vertical Incidence Skywave. -The range for NVIS is typically a radius of 250 to 400 miles. Your actual range will depend on the time of day, the condition of the ionosphere, and the amount of transmit power used.

Thanks for your efforts, – Jeff Bear

JWR Replies: As blog reader “Templar” mentioned, NVIS will not work at CB frequencies unless there are exceptional ionospheric conditions. NVIS is generally limited to the 2-10 MHz range. Higher frequencies usually punch through the ionosphere. (This exaggerated scale illustration from QSL magazine sums up ionospheric skip.) As I mentioned in my novel “Patriots”, the key advantage of NVIS for HF transmission is that it is very difficult to locate via radio direction finding if the intercept outstations are beyond groundwave reception distance.