https://stream.echo6.co/videos/watch/06e0a165-9538-47b4-b9a3-220fbad9d565 About an amazing 3 terminal voltage regulator IC that can amplify audio, driving a speaker from a crystal set with few other parts needed. Sources and further reading: https://www.onsemi.cn/PowerSolutions/document/TL431-D.PDF, http://www.techlib.com/electronics/crystal.html, http://vu2ppp.com/_simple_audio_amplifier_using_tl431, http://theradioboard.com/rb/viewtopic.php?t=7920, http://theradioboard.com/rb/viewtopic.php?t=6733, PS: If you liked this video please consider supporting Amateur Radio VK3YE by: Subscribing on YouTube, Checking my books page at https://books.vk3ye.com, Shopping on Amazon via: https://amzn.to/3iiDQXv, or, Shopping on eBay via: https://ebay.us/i9DuWP (then if you buy something I'll get a small commission at no cost to you) Sun, 26 Apr 2026 15:50:47 GMT https://validator.w3.org/feed/docs/rss2.html PeerTube - https://stream.echo6.co https://stream.echo6.co/client/assets/images/icons/icon-512x512.png https://stream.echo6.co/videos/watch/06e0a165-9538-47b4-b9a3-220fbad9d565 All rights reserved, unless otherwise specified in the terms specified at https://stream.echo6.co/about and potential licenses granted by each content's rightholder.