https://stream.echo6.co/videos/watch/9f920502-0e99-44b5-9aa7-7383db8d1851 *Special Thanks to @extechs on Twitter for putting the compiled bins/firmwares, I somehow managed to build, into a nice zip file with only the necessary files. That's after fully testing everything and sharing a great amount of CalypsoBTS knowledge with me! After a few tries, here's a confirmed working solution that uses DragonOS Focal. Everything in the video is happening on one laptop, that includes the running of YateBTS to create the initial BTS for the c139 to sync to. Loader, Transceiver, and firmware has now been tested with the c139. Pay close attention to the steps and it should be easily reproduced using the upcoming DragonOS Focal R20. In case there's any confusion, YateBTS is only being used to create the network for the phone to sync to, ideally you would sync to an existing GSM network. The Samsung S4 DID NOT connect to the YateBTS network - it connected to the CalypsoBTS network. Also, I'm almost certain the c139 needs the power supply plugged in after loading the firmware. Follow @cemaxecuter on Twitter for more DragonOS and SDR info. Become a patron @ https://www.patreon.com/cemaxecuter *** Transmitting on active GSM freqs is likely a huge legal issue no matter where you are located. Take all precautions necessary to avoid doing anything that could interfere with active towers, ensure you use some sort of shielding to prevent RF leakage outside of your own workspace, and only use this with your own personal equipment as I mention in the video. No part of this was used to obtain any user information or otherwise, it's strictly being used to understand and educate myself on GSM. Sun, 26 Apr 2026 17:29:08 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/9f920502-0e99-44b5-9aa7-7383db8d1851 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.