https://upload.wikimedia.org/wikipedia/commons/a/a4/Amfm3-en-de.gif
Radio amateur call sign finder and identifier. After entering the call sign or just the prefix of the brand, it identifies the brand and displays the countries of the given radio amateur. Simply PHP code that does not need any database or java script.
Very simple deployment on a web server supporting PHP
DEMO
https://data.ok2hss.cz/HAM/PrefixLooup/index.php
