Archive for May 2020

Watch Radio Modulation Depth for best Signal Clarity

Set Radio modulation Depth for optimum Clarity For the sake of optimum clarity and intelligibility of radio transmission, the radio modulation depth must be controlled by ensuring that the microphone input level is maintained well within the automatic Level control (ALC) correction range of the modulator. Failure to do so would result in the introduction of audio distortion. Overdriving the modulator will invariably result in the creation of unwanted AF harmonics and spurious products. Consequently, the intelligibility of the demodulated audio on the receiver at the DX end will also suffer proportionately. Several ill-effects of overmodulation will begin to surface. In extreme cases, the overmodulating radio station will begin to splatter across the band. However, with the modern radio transmitters, sideband splatter is usually not the problem. Nonetheless, this could have been a huge problem in earlier transceivers because it would have produced spurious RF components across a significant portion of the band. At times the splatter could have extended across the entire band. This kind of slatter from just one operator might have rendered the band more-or-less useless for... Click Here to Read Full Article […]
HF radio propagation - summer of 2020

Global HF Radio Propagation Openings – The Summer of 20

HF Radio Propagation Outlook – The Summer of 2020 In the Summer of 2020, the HF Radio Propagation openings are not so frequent as one would expect under normal circumstances. The reason, as we all know is on account of the phase of the 11-Year Sunspot Cycle that we are going through at this time. The 24th Solar Cycle has ended while the 25th cycle has yet to pick up steam. We are placed at the cusp, which appears like a deep broad valley when observed on a graph. As a consequence, the prevailing SSN is either extremely low or zero (0) most of the days. The 10.7cm Solar Flux Index (SFI) is also near the rock bottom. The solar magnetic activity, as well as the energy and particle ejections, are rather placid and limited. For our friends living on the Southern side of the Equator, the phrase, Summer of 2020, may not sound right because it is the winter for them. I totally acknowledge this reality but would request them to bear with me on this matter with regards... Click Here to Read Full Article […]

A Typical 40m HF Band Opening – A Graphical Rendition

40m HF band opening – Animated view Here is an animated graphical rendition of a typical 40m HF band opening transition scenario that I have modeled to provide a pictorial insight into the process. Any animated graphical rendering of HF band propagation opening as it gradually unfurls with the passage of time over the global canvas is a treat to watch. We all know that as a band opening begins to occur, the radio propagation prospects into distant land begin to unfold. This is a gradual process and is primarily dependant on the rotation of the earth on its axis leading to a change in illumination of the globe by solar radiation. As we daily progress through the diurnal (day/night) variation, we expect these changes to play out. On account of the above phenomena, the plasma density of the ionospheric layers above the earth also continuously alter their characteristics in terms of their charge densities, thickness, and height. During the night, the D-layer dissipates while the E-layer practically disappears due to excessive thinning of its plasma density. The F1 and... Click Here to Read Full Article […]

Click social media icons to share article

1 Star2 Stars3 Stars4 Stars5 Stars

(1 votes, Rating: 5.00) - Please vote the article with your valuable star rating. Thanks! Basu (VU2NSB)

Loading...
Ham Rig Reviews Coming Soon

SSN SSNf(10.7) – Real-time Solar Data

Recent Articles & Posts

  • Multiband End-fed Half-wave EFHW Antenna

    Multiband End-Fed Half-Wave EFHW Antenna The End Fed Half Wave antenna or the popularly known EFHW antenna has been around almost ever since the inception of HF radio. Nevertheless, the EFHW antenna had in the Read More…

  • SSN, SFI, Solar Data for HF Propagation

    SSN, SFI, Solar Data for HF Radio Propagation Here are some of the important Solar activity parametric data that are responsible for influencing the behavior of the Ionosphere on earth. These in turn, are instrumental Read More…

  • Learn CW Morse Code – Lesson Set 2

    Learn CW Morse Code – Lesson Set 2 This is the Lesson Set -2 in our multi-part series of CW Morse Code hands-on tutorials where we will introduce numerals and a few important punctuation marks Read More…

  • Learn CW Morse Code – Lesson Set 1

    Learn CW Morse Code – Lesson Set 1 This article on Learn CW Morse Code – Lesson Set 1 is the first in our series of lesson sets for beginners and perhaps others too, to Read More…

  • Learn CW Morse Code – Get Started

    Learn CW Morse Code – Get Started If you are reading this article, then in all probability you either wish to learn CW Morse Code from the scratch or are one of those who learned Read More…

Newsletter Subscription

Subscribe to our newsletter and receive regular updates on new posts and articles.
We keep your data private and share your data only with third parties that make this service possible. Read our Privacy Policy.