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 permissable in your locale.

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - Josh

Pages: [1] 2 3 ... 154
Equipment / Re: Whats wrong with my antenna?
« on: March 20, 2019, 1848 UTC »
On the use of coax as an antenna you run into a few things.

One is only the outer shield is impinged upon by the passing rf wave, so whatever length of coax you have, that's the total antenna aperture, not the inside center conductor PLUS the outer shield.

Another aspect is if you only connect the center conductor to the radio and no antenna elements on that same coax, the only way a signal can get to the center conductor from the outside is via capacitive coupling, and that will be very scant since only the very outer layer of the shield has rf flowing on it, not the inside facing surface of the shield.

It doesn't take much of a conductor to make for a decent vlf/mf/hf antenna, USN did a study and found that with a decent groundplane (ie a US warship plus the entire ocean) you only needed about 6 feet of wire, a coupling device to make the hi to lo z transformation would of course be spliced in between coax and antenna.

Case in point, I had a 1/4w cb antenna on top of some mast up about 10m, with a decent grounding wire run from base to ground stake. That thing was amazing from vlf to hf and on 6m too, of course I had to use a tuner for best results but it was an excellent dx antenna. Not very good at nvis at all but an amazing dxer.

Utility / Re: 11232 USB 2144Z 08JAN19
« on: March 20, 2019, 1758 UTC »
Trenton Mil working Coast Guard 2006 for pp 1756Z 20MAR19
2006 is unheard here, bands been poorly.

Software / Linux distro for sigint
« on: March 20, 2019, 1730 UTC »
SigintOS: A Linux Distro for Signal Intelligence
Recently we've heard of a new Linux distribution called SigintOS becoming available for download. SigintOS is an Ubuntu based distribution with a number of built in signal intelligence applications for software defined radios such as RTL-SDRs and other TX capable SDRs like the HackRF, bladeRF and USRP radios.

The distro appears to be very well executed, with a built in GUI that grants easy access to the some common sigint tools like an FM and GPS transmitter, a jammer, a GSM base station search tool and an IMSI catcher. SigintOS also has various other preinstalled programs such as GNU Radio, gr-gsm, YatesBTS, wireshark and GQRX.

The OS also teases an LTE search and LTE decoder which to access requires that you get in contact with the creators, presumably for a licencing fee. Regarding an LTE IMSI catcher they write:


I've heard these creatures also thrive in the 160m band, irritating HAMs.

Satellite, Radiosondes and Other VHF/UHF Signals / Re: UHF mil air
« on: March 20, 2019, 1711 UTC »
Unid air refuel ongoing, 336.100 (AR455 primary, 455 runs across the top half of old kaintukee) 1630Z 20MAR19
36 and 60 are the players.

"We're looking for a seat swap for some precontact training and some breakaways

Can do, and clear to contact

60 contact

36 return astern"

Also, muxers was muxing on 337.3 a few hours ago.

General Radio Discussion / Re: DRM Handbook
« on: March 19, 2019, 2221 UTC »
There's a much longer tradition in India for people in government to just come out and say this is how it's going to be, and they get away with it. Forcing everyone to buy new ambc radios is just one effort, removing the most popular bills from currency was another.

In contrast, it was bad enough they forced everyone to get new tv sets/tuners in the US for the new digi standard, I don't think forcing am and fm listeners to buy new radios would have gone over well. I never knew how much I missed out being unable to see zits and/or boogers of the stars of stage and screen before.

Utility / Re: 11175 USB
« on: March 19, 2019, 2146 UTC »
LONG HAND with an lengthy eam accompanied by someone in the background whining and moaning about "what are we gonna do now", lol. 2130Z 19MAR19


This seems very interesting. Is there a way to figure out the geographic location of the beacon based on the CW information sent from the beacon? (Rough location anyway) Also any direction towards a frequency list would be great. I'll look around the boards a little now. Thanks


Utility / Re: 11175 USB
« on: March 18, 2019, 1742 UTC »
Home Of Strategic Command And Some Of The USAF's Most Prized Aircraft Is Flooding
The home to America's prized RC-135 "Rivet Joint" strategic reconnaissance and E-4B "Nightwatch" Advanced Airborne Command Post aircraft, as well as others, and the headquarters of U.S. Strategic Command (STRATCOM), is flooding with water from a swollen Missouri River.

At least the flood prone nuke plant 30 miles to the north is no longer in operation.

So hes's father of a generation of script kids. I'm ashamed for him.

Are you all running the same sdr with spurs on the same freqs? Does the noise go away with propagation?
That looks kinda strong to be spread all over the southwest like that and not be locally generated. Also, if you're brave enough to have java installed, try to tdoa the sigs and see where they come from.

Equipment / Re: Whats wrong with my antenna?
« on: March 17, 2019, 1753 UTC »
Dmm each connector and adaptor, check each cable, you'll find the problem(s).

SDR - Software Defined Radio / New SDRuno vailable
« on: March 15, 2019, 1816 UTC »
SDRuno – v1.3 (14th Mar 2019)

SDRplay is pleased to announce the release of SDRuno v1.3. This is a major upgrade to SDRuno, which adds a number of important new features and is intended for all RSP models including the now discontinued RSP1.

"Major new features include:

Frequency Scanning (for both frequency ranges and stored memory panel lists)
I/Q → Audio Output (for CW Skimmer for example)
A new configurable IF AGC scheme"



Pages: [1] 2 3 ... 154