We seek to understand and document all radio transmissions, legal and otherwise, as part of the radio listening hobby. We do not encourage any radio operations contrary to regulations. Always consult with the appropriate authorities if you have questions concerning what is permissible in your locale.

Subject / Started by Last post
4 Replies
846 Views
Last post April 04, 2021, 1246 UTC
by ION Radio
4 Replies
847 Views
Last post November 08, 2020, 2107 UTC
by flexoman61
1 Replies
847 Views
Last post November 24, 2018, 2034 UTC
by ranco
4 Replies
847 Views
Last post March 24, 2023, 0217 UTC
by blw
0 Replies
847 Views
Last post May 18, 2014, 1514 UTC
by ChrisSmolinski
1 Replies
847 Views
Last post August 18, 2017, 2218 UTC
by Helicaster
13 Replies
847 Views
Last post March 23, 2025, 0018 UTC
by dxwingr
2 Replies
847 Views
Last post March 03, 2025, 2123 UTC
by Radiouser
5 Replies
847 Views
Last post May 08, 2023, 0003 UTC
by Radio Star
UNID 6925 USB 1830 UTC 1/18/16

Started by JoeFLIPS

0 Replies
847 Views
Last post January 18, 2016, 1831 UTC
by JoeFLIPS
3 Replies
847 Views
Last post May 05, 2024, 1621 UTC
by N2MLP
0 Replies
847 Views
Last post September 28, 2012, 1215 UTC
by Sealord
0 Replies
847 Views
Last post February 04, 2013, 1451 UTC
by Sealord
8 Replies
847 Views
Last post August 16, 2025, 0202 UTC
by William Hassig
2 Replies
847 Views
Last post June 21, 2020, 0228 UTC
by cheesehed
1 Replies
847 Views
Last post May 12, 2018, 0345 UTC
by PghScanner
0 Replies
847 Views
Last post December 19, 2016, 2255 UTC
by R4002
0 Replies
847 Views
Last post June 17, 2013, 1223 UTC
by ChrisSmolinski
3 Replies
847 Views
Last post March 19, 2025, 2214 UTC
by hsmith77
5 Replies
847 Views
Last post August 31, 2025, 1412 UTC
by N2MLP

 

Normal Topic
Hot Topic (More than 15 replies)
Very Hot Topic (More than 25 replies)

Locked Topic
Sticky Topic
Poll


HFUnderground T-Shirt
HFUnderground House Flag
by MitchellTimeDesigns