On 2025-11-04 03:27, ‘Andrew Thornett’ via Society of Amateur Radio Astronomers wrote following in bold, then Marcus Leech responded with answers in italics. Hi All, Interesting discussion on the resistor…
I made following comment on SARA mailing list 3/11/2025. “I was talking about the Nooelec SAWBird H1 LNA, which it turns out has 3 versions. Worth saying that it is…
The Heat Index is one of the most useful composite weather measures, especially for gauging human comfort and safety in warm conditions. Here’s a concise breakdown: 🔹 What It Is…
There are a few possibilities depending on what you’re interested in:
These results were presented by Andrew Sutkowski at the BAA Hydrogen Line Sub-Group Meeting 3/11/2025. His preference is the WVURAIL ones, which are designed as part of the DSPIRA project,…
In a cantenna for 1420 MHz, how far from bottom of can should be the monopole? Short answer: place the monopole about a quarter of the waveguide wavelength (λg/4) up…
Andrew Sutkowski checked his feed and found monopole probe made of 1/8 inch copper tube far better at picking up 1420 MHz hydrogen signal than bare copper wire (information from…
Here’s a comparison of typical power consumption (no peripherals or display) for each device, measured at the wall under different workloads. Device Idle Power Moderate Load (e.g. data logging, web,…
A Kumar choke (often called the VE4MA or Kumar feed/choke) is a choke-ring / cavity around a horn/feed that suppresses unwanted surface and coaxial currents and “traps” or reflects energy…
Short answer: No—the dish doesn’t change the waveguide dimensions of the cantenna.The can’s internal diameter and the probe/back-short geometry are set by your operating frequency and waveguide mode, not by…
Admin