Start here – Perform Basic Diagnosis

Radio Frequency Interference (RFI), QRM or noise, has become one of the single largest impediments to HF operation in any urban environment.  This post covers the basic philosophies to help you identify and get on track to resolve your noise issues. RFI in some urban environments may appear unsolvable, but by working through the methods […]

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List of Tools

Here is a simple list of tools you’ll need to start searching for noise: a small DF loop, like this one for VHF and UHF, a Yagi or other directional antenna. Say something around 8db gain a simple wide band AM receiver or a 2/70 handheld for higher frequency work – two suitable options are […]

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Example – Basic Diagnosis

This is a simple example of how you might conduct the first step in identifying the noise/s.  John has moved to a new QTH has has some noise issues. John is using the log sheet and profiling sheet found under Templates.  He is keeping a detailed journal. John notes that every time he turns on […]

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Identifying the noise – Useful links

This post provides links to some useful sites and resources to help you identify your noise.  Please send us any additional resources or links you know about. Two common and sometimes misunderstood terms (or Q-codes) are QRM and QRN.  The images below provide a high level explanation of the difference between QRM and QRN. This […]

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