About this episode
Foundations of Amateur Radio
Noise la la la la la hinders if I were a rich man effective a noise annoys an oyster communication but a noisy noise annoys an oyster more.
Or said differently, when you're trying to communicate, something that the hobby of amateur radio does in spades, you'll need to deal with a phenomenon called noise.
This noise comes in different forms, but the effect is the erection of barriers to successful communication. We refer to the impact of noise as a signal to noise ratio or SNR, the signal being the desired information, the noise the undesired interference. Expressed in decibels so you can deal with a massive range using a small number, an SNR greater than 0 dB means that the signal is stronger than the noise.
Building a shack requires that you consider noise in many forms. If you've been a radio amateur for a few moments, your mind is likely to head straight for the hiss, crackle and pop you might hear whilst attempting to communicate on HF, but there's a few other things to discuss.
There's all sorts of electronic noise received by your radio. In addition, there's audio noise picked up by your ears, and often your microphone. Then there's the noise that you produce, either from your transmitter into the rest of the building, or from your mouth or speakers into the ears of the people you share the space with.
Starting with audio, having a space that you can close the door on is a good way to limit the noise coming into and leaving your shack. An alternative is to wear headphones and generate text to speech, or prerecord your voice, ready for a contact, potentially ideal for contesting, not so much for free form discussion. Another consideration is audio from other radios, including those tuned to a local broadcaster, or aviation frequencies. In other words, if you're transmitting with a microphone, make sure that there's no other audio coming through. In some cases it's even illegal to transmit that audio, but in all cases it's noise that makes communication more difficult.
This kind of audio noise mitigation is pretty straightforward.
In stark contrast, achieving the same with electronic noise is pretty much a balancing act between budget and effectiveness.
The impact of noise is inversely proportional to distance. Essentially, the closer it is, the more impact it has. With that in mind, when you start dealing with noise, start nearby and work your way out. As you eliminate the nearby noise, other sources will become apparent.
Without turning this into a noise mitigation class, the process is essentially one of elimination. First locate the noise source, then eliminate it. That's easier said than done.
For example, if the noise source is a power supply sitting on your bench, you can turn it off, except if that power supply is the one powering your radio, so perhaps I should say: "attempt to eliminate it" instead.
There's plenty of ways to have a go at this and volumetric
