I should probably count myself lucky. My interest in radio started with short wave listening in the late sixties, a time before the age of the microprocessor, let alone the internet. A time when the twisted copper pair, owned by the then GPO (General Post Office) was used to deliver no more than just a standard analogue phone service. Those halcyon days of giving “three rings” to signify something significant, like I’m ready to be picked up, or I’m setting off now.
It was during this time that I would spend hours tuning around all the different short wave bands to catch that elusive South American tropical band station on 60M, or some North American medium wave DX with a home made loop antenna constructed from bamboo canes and the windings of transformers I’d scavenged from scrap equipment at local factories. Once I’d saved a little pocket money, plus any money I’d received for birthdays and Christmas, I’d buy another cheap, ex forces radio, one of the many that were available on the surplus market. All this long before I decided to get my amateur radio licence when I was 16.
Anyway, I digress. The reason for this post is to highlight that today, in a normal suburban location like mine, it’s now all but impossible to listen to the short wave any more. Back then the simple difference was that the only sources of noise on the bands, besides natural noise such as static and lightning crashes, where things like TV line timebase, badly suppressed ignition systems on cars, motor cycles, and worst of all in the summer, lawn mowers. But all those sources were transitory. Once the car had passed, so had the noise. There was virtually nothing in the house that would impinge on the ability to listen to the short wave bands as nature intended.
Nowadays, many devices in the house are connected, with wifi and bluetooth etc. And worse, most now employ switch mode power supplies that simply ooze interference. Sure, there’s the CE mark. But who doesn’t buy cheap stuff off Amazon? I’ve recently pulled apart some of this kit and found that the design and construction certainly doesn’t meet the accepted standards required to suppress interference.
Lately, the standard (easiest) way of distributing the internet around your house employs PLT, which allows you to (for example) place a remote set top box in another room. The technology uses your house wiring and as a result broadcasts constant noise and harmonics right the way up to 100MHz. So it’s hardly surprising that you can’t tune anywhere now without hearing a constant racket across all the bands. The same technology is used to deliver the internet to you down your phone line. If you’re to be able to even hear anything, you’ve to look to digital signal processing techniques just to make a dent in the noise levels.
I guess the only satisfactory method of getting “clean” airwaves is to take a portable radio out to middle of nowhere and try from there. But that defeats the joy of armchair listening, something which I recently thought I’d try and get back interested in. I’ll try things like getting the aerial away from the house, but then it’ll be closer to another house and hence back to square one. As an experiment I recently powered the radio from a battery and cut (well not literally), the mains to the house. The noise did drop slightly, but I was still picking up all the crud from the houses nearby.
So, the latest copy of World Radio TV handbook (2018) I just got may have to gather dust. It’s unlikely I’ll ever hear anything like I used to be able to. Interestingly one of its lead articles this year is all about noise, and it too concedes that it’s just the way it is now.
Of course I love all the technology that today brings, and no, I wouldn’t want to go back to the good old days, but everything usually comes at a cost. And today, one of those costs is that I can no longer listen to the short wave bands.
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Well in my place there’s wifi and hard wired. Our machines are hard wired – but on occasion phones and tablets connect via wifi.