M.A.R.C

Ham Radio Gear Detector.

Another Nice Saturday, Few Contacts on the Radio
Then Lunch.
M7KAL Richard enjoyed him self on the Radio.
Till next time 73s, & thank you for coming. Cu again.

Nice to have Richard M7 KAL come to visit as always while inalta on Holiday.

SAQ Transmission from the Club.

05 July 2026 SAQ transmition July 5th 2026 from 12:45 to 13:05

Radio wave propagation is the way radio signals travel from one antenna to another. Understanding propagation is one of the most important skills for every ham radio operator because it determines how far and how reliably signals can be received. Ground wave propagation follows the Earth's surface and works well on LF and MF bands for local and regional communication. Sky wave propagation uses the ionosphere to bend HF signals back to Earth, allowing contacts over hundreds or even thousands of miles without satellites. Line-of-Sight (LOS) propagation is used on VHF and UHF bands, where signals travel in a straight path, making it ideal for repeaters, simplex communication, and emergency radio. Tropospheric propagation can occasionally extend VHF and UHF range far beyond the horizon through ducting or troposcatter, especially during favorable weather conditions. Space wave propagation includes satellite communication, enabling worldwide contacts through amateur radio satellites. By understanding these propagation modes, ham radio operators can select the best frequency band, antenna, and operating time to achieve reliable local, regional, and worldwide communication.

A band-pass filter allows a specific range of frequencies to pass while reducing signals below the lower cutoff frequency (fL) and above the upper cutoff frequency (fH). It combines the behavior of a high-pass filter and a low-pass filter, making it useful for selecting only the desired portion of a signal. The center frequency (fcenter) is the midpoint of the passband, while the bandwidth is the difference between fH and fL. The quality factor (Q) indicates how selective the filter is. A higher Q results in a narrower passband with better frequency selection, while a lower Q provides a wider passband. Band-pass filters are widely used in radio receivers, audio systems, wireless communication, biomedical instruments, signal processing, and measurement equipment to isolate useful signals and reject unwanted noise and interference.