What happens if I put two x RF DC-22MHz filters in parallel?
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Short version: “Parallel” doesn’t help—and can make things worse. Here are the three ways people mean “parallel,” and what actually happens: If your goal is to move the −3 dB…
I have a mini circuits DC-22MHz filter. Would it be possible to slightly adjust range up by 2MHz with extra components?
Short answer: not really. Mini-Circuits “DC–22 MHz” parts are fixed, 50 Ω-matched, sealed networks (usually elliptic/Chebyshev LC). To move the cutoff up by ~2 MHz you’d need to reduce the…
How to run Linux under Windows
You’ve got three good ways to run Linux under Windows 11, depending on how much integration or isolation you want. Here’s a breakdown: 🥇 1. Use WSL 2 (Windows Subsystem…
Protected: Beta Test version of Ted’s new ezCol and ezCon for SDRplay 1/11/2025
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Pictures of meteors detected by radio meteor scatter at LRO
Pictures can be accessed via download of ZIP archive below: https://www.astronomy.me.uk/wp-content/uploads/2025/11/Pictures-for-Astronomy-Now-011125.zip
What are best specifications for cavity filters for 1420 MHz Hydrogen Line work?
For 1420 MHz (the H I line at 1420.4058 MHz), the “best” cavity filter depends on where you place it in the chain (pre-LNA vs post-LNA) and what you need…
How to control 12 V and 26 V coaxial relays through USB.
Good — that’s a nice setup for remotely switching antennas, receivers, or feed chains. Let’s outline how to get both coaxial relays (12 V and 26 V types) under PC…
Ultra-wideband (UWB) cavity filters
Ultra-wideband (UWB) cavity filters are specialized RF/microwave filters that maintain the low loss, high power handling, and excellent selectivity of traditional cavity filters, but over a much wider fractional bandwidth…
What is best type of power supply to use for bias-tees that power LNAs at dish feed in hydrogen line systems?
Short answer: use the quietest DC you can. In practice that means: Why (and how) Hydrogen-line work is extremely sensitive to conducted and radiated hash. Switching PSUs produce combs that…