The following LED lights items have been reported as amateur radio friendly by VK Hams. QRM.guru and the developers are unable to independently verify these products and have published these recommendations in good faith. During tests conducted in December 2019, the following products from five different manufacturers resulted in a clean bill of health. Other […]
Category: Case Studies
Tracking and resolving Garage Door Controller noise – noisy PSU
Another noisy garage door causing havoc on HF. A group of hams decided to use QRM guru to help with some unknown RF noise. Using the DF Loop the garage door opener was found to be the cluprit The garage door controller was removed and taken to the workshop for further analysis. Model Herculife RDO-V12 […]
Tracking and resolving Garage Door Controller noise – software setting
Thanks David, a VK3 amateur for this article. Like many amateurs, I live on a suburban block surrounded by local neighbourhood RF hash. My noise level on 40M was typically S9 plus with crackling interference. In the past the basic checks were completed, LED lights, solar inverter etc and without any real conclusion, I became convinced […]
MFJ-1025 Noise Cancelling Signal Enhancer
Craig VK3MET demonstrates the effectiveness of MFJ interference cancelling technology that uses a sensing antenna to suppress interference by introducing an out-of-phase sample signal. Such tools can prove very effective in some situations. In ths case the noise cancelling technology is suppressing what is most likely a plasma TV noise source. (disclaimer: neither the author, […]
Locating Power Line Noise
The below videos give a real world example of power line noise suffered by Allan VK2CA. The second video shows first hand how you can use a simple VHF/UHF receiver to narrow down the offending power pole. QRM.guru thanks Allan for providing these videos. This video illustrates first-hand the horrible sounds that […]