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
2 Replies
2035 Views
Last post November 22, 2023, 1915 UTC
by KVKHFF (Andy)
2 Replies
1713 Views
Last post December 23, 2023, 1018 UTC
by TRI International
2 Replies
2634 Views
Last post January 09, 2022, 0204 UTC
by ~SIGINT~
2 Replies
4588 Views
Last post August 24, 2024, 1851 UTC
by UtilitySeattle
2 Replies
1993 Views
Last post September 07, 2022, 0212 UTC
by Sky
2 Replies
2194 Views
Last post November 24, 2022, 1613 UTC
by UtilitySeattle
2 Replies
3249 Views
Last post April 18, 2017, 1012 UTC
by Daniel Wyllyans
2 Replies
3144 Views
Last post November 17, 2017, 0454 UTC
by Matt_B
2 Replies
2516 Views
Last post September 16, 2023, 1312 UTC
by TRI International
2 Replies
1585 Views
Last post December 16, 2023, 2128 UTC
by TRI International
2 Replies
3635 Views
Last post November 19, 2017, 0803 UTC
by Looking-Glass
2 Replies
3178 Views
Last post November 08, 2017, 1900 UTC
by Matt_B
2 Replies
1386 Views
Last post December 16, 2023, 1410 UTC
by TRI International
2 Replies
4222 Views
Last post October 17, 2017, 2237 UTC
by Kilokat7
2 Replies
2830 Views
Last post November 19, 2021, 1346 UTC
by EA2NR
2 Replies
4349 Views
Last post November 20, 2018, 0057 UTC
by NJQA
2 Replies
3847 Views
Last post June 13, 2024, 0744 UTC
by TRI International
2 Replies
4641 Views
Last post December 03, 2016, 1713 UTC
by Daniel Wyllyans
2 Replies
2821 Views
Last post November 23, 2019, 1715 UTC
by Edgar Souse
VLF and LF

Started by NJQA

2 Replies
3558 Views
Last post October 05, 2019, 0230 UTC
by NJQA

 

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