There are not a small number of questions that ask about how to build something not too specific:
- Low parts count CW HF receiver?
- How can I construct a practical loop antenna for 2m band?
- Is there a simple, DIY, antenna suitable for HF receive only?
- Simple DIY AM receiver for 25/28 MHz
- How can I get started with a Home Brew QRP?
- Simplest, smallest antenna for tuning WWV, WWVH?
(As I was searching for these, I found just searching for "simple" to be very effective)
The trouble with many of these questions is that they don't have any single answer. There are thousands of radio and antenna designs out there. Asking for one that's "simple" or "practical" or "easy" or "cheap" doesn't narrow it down much.
The answers tend to be someone's favorite solution, their favorite antenna, a kit they are familiar with, etc, with no particular merit beyond that it's familiar to them.
A good answer which isn't usually posted is "try searching for '_____ schematic'", which usually turns up a few thousand options.
I think this is a great case for the "primarily opinion-based" close reason, but I have never seen it used. Should these questions be on topic, or should they be closed?