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HF Beacons / 5295.0 AM Ten Count Beacon
« on: August 20, 2021, 2241 UTC »
5295.0 kHz AM Synthesized Voice Beacon "Ten Count"

2130UTC 2021AUG20 started logging of an unknown AM voice transmission already in progress.
Signal approximately -95dBm with fading, weak readable.
2159UTC 2021AUG20 noticed that this beacon ceased abruptly in a mid-transmission.

PLAY AUDIO of the 5295 AM Ten Count Beacon

This UNID HF beacon or test transmitter was heard transmitting a series of repetitive sequential transmissions.
Some occasional gaps were heard between the repetitive sequences, which were about 3 to 7 transmissions in each sequence.
Each Transmission Duration: 10 sec.
Each Transmission Repetition Rate: 20 sec.

Sequence timing of each transmission was approximately as follows:
Carrier On, Silence for 500 mSec.
AM Modulation Beep Tone 440 Hz for 370 mSec.
AM Modulation by synthetic Asian male accented voice type EE (English), "Testing 1-2-3-4-5-6-7-8-9-10" for 8.2 sec.
Silence for 500 mSec, Carrier Off.
Repeat at next 20 sec clock.

Appears to be standard AM (Amplitude Modulation) with both sidebands.

Estimated area: West Coast of North America or Eastern North Pacific.

2020 NOV 30 0400UTC
5377.7 kHz USB voice
Asian language fishing fleet, likely S. Korean.
4 or 5 stations.
Approximate location today: a few hundred miles off the coast of Oregon and California.
Often heard nightly 0400-0530UTC spinning big fish stories to each other on this frequency.
Motors and other industrial ship background sounds.

Note: this isn't a normal Maritime HF channel or band

27 MHz ISM Fish Hook Swisher Interference RFI EMI RF HF Sealers Heaters Welders Worldwide 11 Meter Band

Strong ISM type signals with a fish hook signature on the waterfall spectrum are observed worldwide in the 25 MHz to 27 MHz range.

Fish hook swisher signals may originate from poorly shielded ISM devices.

The industrial, scientific, medical (ISM) band at 26.957 MHz to 27.283 MHz overlaps the 27 MHz CB band.

Many types of industrial RF plasma devices, such as RF welding, plasma chamber deposition, plasma torch, plastic sealing or welding, or RF cutting machines use 27 MHz.

Other types of RF ISM type equipment, power RF devices, or RFID equipment may also be a source of signals with a similar spectrum signature.

The frequency accuracy of ISM devices may vary widely, and some ISM signals have been monitored operating 1.5 MHz or more out-of-band.

This category of EMI, EMC, or RFI  (ElectroMagnetic Interference, ElectroMagnetic Compatibility, Radio Frequency Interference) is heard intermittently and commonly by CB radio users, and sounds similar to a VFO knob being turned as the transmitter is swished across the band.
The sounds are often described as: "swishing, swisher, spinner, swish, slider, slide, sweep, whoosh, wind, howling, whoop, razzer, whooping".
They can often be much stronger than 11 meter CB radio signals.

Duration of the fish hook swisher signals is approximately 2 seconds to 20 seconds, with most of them averaging around 5 seconds long.

The initial frequency typically sweeps abruptly downward about 30 kHz to 50 kHz, then ends the sweep with a slower frequency change, or a stable frequency, which gives it the distinctive fish hook signature on the spectrum waterfall.

Some fish hook swishers have also been observed with upward frequency sweep, but they are not as common.
Some fish hook swisher signals have been observed having as much as a 400 kHz total sweep range.
Modulated tones, digital dithered, unmodulated carriers, and noisy carriers have all been monitored.

This report includes detailed monitoring of some fish hook swisher signals which were monitored during a very strong Sporadic E (Es) propagation opening which widely covered western USA in mid-2019.
These are not local signals near the receiver, such as switching power supply, computers, or lights.
The signals shown in this report are being transmitted by ISM sources 250 miles to 1200 miles away (400 km to 2000 km).

Report 2019JUN03 1800UTC
ID: various ISM signals, unidentified.
Frequency: 26 MHz to 27.8 MHz.
Signal levels: various, ranging from -130dBm to -70dBm

PLAY AUDIO 27 MHz Fish Hook Swishers compilation recorded in IQ mode at 12 kHz total bandwidth on 2019 June 03 EMI RFI

Spectrum waterfall images showing ISM RFI fish hook swishers in the 27 MHz range:

End of report.

Report 2019APR22 0400UTC

10099.96 kHz AM, WWRB, 2nd harmonic, -22dBc from its 5049.98 kHz fundamental, spewing +10kHz into the 30 metre ham band, strong readable, -87dBm.

5049.98 kHz AM, WWRB, fundamental(ist), :) standard nonsense program content, strong readable, -65dBm.

A world class example of a shoddily engineered shortwave broadcast station.
Fundamental 20 Hz off frequency.
Spewing harmonics up the spectrum.
Dirty audio with AC hum.
Dumpster trash of the airwaves.

Other / 10500kHz Ditter Hopper 2019JAN25 2145UTC
« on: January 25, 2019, 2231 UTC »
Ditter hopper.
When the logged frequencies are monitored simultaneously on separate receivers or instances, it is observed hopping repetitively from one freq to the next higher frequency in sequence.

Depending on which frequency or time interval is listened to, it sounds like either continuous dits, or groups of 3 dits.
First was logged on 14350 kHz around 1940UTC, and then a closer look at it yielded other companion signals at around 2145UTC.

2019JAN25 2153 UTC

10150.0 kHz CW, frequency hopping, good readable, -112 dBm
10500.0 kHz CW, frequency hopping, good readable, -110 dBm
14350.0 kHz CW, frequency hopping, readable, -120 dBm
Timing Notes:
Pattern on 14350 kHz. approximately 28 millisecond dit duration, 3 dits at 1.411 second repetition rate, 9.4 second pause.

Note: noise level in 3 kHz bandwidth approximately -130 dBm.

2019JAN25 2200 UTC
Signal ceased on all logged frequencies simultaneously at the top of the hour.

Frequencies logged are noted to be in standard increments of kHz, and sequential hop activity is similar to the operational pattern of the Son of Yosemite Sam hopper from November 2018.

The 9 second cycle is similar to Son of Yosemite Sam.

PLAY AUDIO RECORDING 14350kHz Ditter Hopper 2019JAN25 2153UTC

Wild guess: It is a low power frequency hopping antenna system being tested, probably located somewhere in southwestern USA.


North American Shortwave Pirate / UNID 6925.15 AM 0203UTC 29 DEC 2018
« on: December 29, 2018, 0207 UTC »
2018DEC29 0203UTC
6925.15 kHz AM, dramatic voices, old radio show?, fading, lightning static, very weak unreadable, -125 dBm

HF Beacons / 2 MHz Western USA Beacons
« on: December 27, 2018, 0428 UTC »
A thread looking at some of the 2 MHz beacons in Western USA.
If you find these reports useful, please feel free to reply with comments or feedback.

2018DEC27 0358UTC (local night time)

2008.41 kHz CW, UNID, ditter, beacon, land, weak readable, -120 dBm.
Note: This beacon's timing is somewhat variable, possibly due to voltage or temperature.   
Dit duration: approximately 170 to 200 milliseconds.
Dit repetition rate: approximately 1.5 to 2.7 seconds.
ON cycle: 90 to 100 seconds.
OFF cycle: 3.0 to 3.3 minutes.

2097.30 kHz CW, "A", Morse, beacon, 9.9 second repetition, good readable, -107 dBm.

PLAY AUDIO recording of 2008.4 kHz CW UNID ditter beacon 2018DEC27 0327UTC recorded in USB mode at 2008.0 kHz with 300 Hz bandwidth passband filter.

PLAY AUDIO recording of 2097.3kHz CW A Morse beacon 2018DEC27 0358UTC good and clear with a little background lightning static.

Image below shows the nearby Pt. Arguello Digisonde ionogram at the time of this recorded log, with good 2 MHz NVIS propagation, foF2 = 2.375 MHz and fxI = 3.0 MHz.

Shortwave Broadcast / R. Timtron 5130.43 AM 0030UTC 23 DEC 2018
« on: December 23, 2018, 0041 UTC »
2018DEC23 0030UTC
"Radio Timtron Worldwide" (aka WBCQ)
5130.43 kHz AM

HF Beacons / 7 MHz Western USA Beacons
« on: December 04, 2018, 2023 UTC »
A thread about 7 MHz beacons around Western USA.
If you find these detailed reports useful or interesting, please feel free to reply with any comments.

Highlight of this report: "HI" CW Morse beacon at 7998 kHz


2018DEC04 1945UTC

7998.12 kHz CW, Morse beacon, "HI", good readable, 9.64 seconds repetition, dit duration 128 milliseconds, -117 dBm.

2018DEC04 2002UTC
7998.12 kHz CW, Morse beacon, "HI", stopped abruptly.

PLAY AUDIO 7998.12 kHz CW Morse beacon HI 2018DEC04 1945UTC

Image below of waterfall shows CW beacon HI morse at 7998.12 kHz on 2018DEC04 1945UTC

Mystery code.
Similar to Wabun (Kana) Code.
What kind of code is this?
What language?
Copied on 4101.4 kHz CW
0540UTC 08OCT2018
night in California

PLAY AUDIO of Wabun-like CW Code

More info about the source, and USB voice audio of operators who are sending the code.

Some of the characters copied in this Mystery Code:

Peskies / Mystery S.Korean Peskies 4100.0 USB 4101.4 CW Pacific
« on: October 05, 2018, 1014 UTC »
0550UTC 05OCT2018
(local night in California)

In the maritime 4 MHz band, in the gap between wild beacons H and W:
4100.0 kHz USB peskies, voice, S. Korean language (KO), informal ship-to-ship, Pacific, good readable
4101.4 kHz CW peskies, quick Morse, ship-to-ship, same Korean ops switching back and forth to voice USB on 4100 USB, callsigns: HL[...], good readable

The odd thing is, that 4100.0 is in between 2 normal marine channels:
4098.0 (Marine HF SSB Channel 412)
4101.0 (Marine HF SSB Channel 413)

Equipment / Mod Black Cat Beacon Kit
« on: September 21, 2018, 0827 UTC »
Here's a theoretically simple, cut-and-jump mod for the existing Black Cat Systems 22 meter Beacon Kit.
The mod provides operation on a different frequency than originally intended: in the frequency range anywhere from about 80 meters to 40 meters.

Note: This is not an official authorized mod. Black Cat Systems had nothing to do with this mod.

Build and test your original kit first the way it was originally designed.
Then if you choose to do this mod, do it while knowing that it started out working OK.
If you mess up your kit, don't blame Black Cat Systems.
When you do this kind of crazy mod, it is totally your own responsibility
Hams can use this mod for a ham band beacon ;)

With the warnings having been duly admonished, onward to the actual beacon mod:

The oscillator.
It's hard to beat a cheap programmable clock oscillator for simplicity of frequency choice.
Fixed-frequency clock oscillators can also be utilized for this purpose.
A programmable oscillator can be ordered from Digikey or another electronics dealer, pre-programmed to any frequency, or a programmer system can be acquired and you can program it yourself.

Theory of the mod circuit:
  • The programmable oscillator is keyed by the microprocessor's keying line, via one inverter of the 74HC02 that had originally been utilized as the crystal oscillator. Since the microprocessor asserts a logic Low on the keying control line for "transmit", the keying line needs to be inverted to key the programmable oscillator's control input (which requires logic Hi for operation).
  • The programmable oscillator (see data sheet) pulls as much 45mA., so power consumption can be reduced by keying the entire oscillator on/off.
  • The oscillator output feeds into the remaining 3 inverter sections of the 74HCO2, which act as as a power amplifier, as originally designed.
  • The Power Amplifier feeds the Low Pass Filter (LPF) which is modded with capacitors and inductors to reduce harmonic energy, with a cut-off just above 7 MHz.
  • The Low Pass Filter output feeds the antenna or dummy load.

Theoretical procedure:
1. Remove Y1 crystal.
2. Remove capacitors C4, C16, C17, C18.
3. Remove Jumper at C16.
4. Remove RV1 and put a jumper on the bottom of the PCB in place of it for full power.
5. Do the other cut-and-jump mods around the 74HC02.
6. Remove the L1, L2, toroid inductors and replace with the 2 new leaded 1.5uH inductors in the Low Pass Filter mod.
7. Add the 3 capacitors C3, C8, C9, in the Low Pass Filter mod and leave all the original capacitors in place.
8. Double sticky foam tape the Programmable Oscillator upside down (dead bug style) to the board in the area where the crystal was.
9. Wire the Programmable Oscillator into the appropriate points on the board.
10. Test the unit on a dummy load or ~50 ohm resistor.

Theoretical Parts List for mod version 1d.
QTY, Description, Value
2pc, Inductor, 1.5uH  part link Digikey
2pc, Capacitor, 470pF part link Digikey
1pc, Capacitor, 680pF part link Digikey
1pc, Programmable Oscillator, CPPC4-HT5RT part link Digikey

Below: Schematic of theoretical mod version 1d.

Below: Large size schematic of theoretical mod version 1d.

You own it, it is yours to break.

Report 0510UTC 19SEP2018
0507UTC, 6870 kHz USB, "Mix Radio International", smooth jazz saxophone music, S7 good signal, lightning static in background
~0510UTC, 6870 kHz USB, "Mix Radio International", off air

HF Beacons / Wild Beacons
« on: September 11, 2018, 0232 UTC »
Beacons Gone Wild!

Let's talk about the kind of pirate beacons... wild beacons... that may be set up in the wilderness, park lands, forests, floating on the ocean or lakes, or perhaps upon urban structures. These are especially popular in the Wild West.

  • Is the name "wild beacon" appropriate?
  • What other names have been used to describe these types of beacons?
  • What motivates wild beacon creators?
  • What are some of the strategies and best implementations for creating a wild beacon?
  • What is the projected lifetime or chance of survival for a wild beacon?
  • Why do we like to listen for wild beacons?

Creators of wild beacons may tend to hide them in places where they hope ordinary people wandering around won't find them. Of course, the creators know that they can be located by RDF. But, if the beacon is in an area without roads, even if the area is known, it can be difficult to actually locate them due to rough terrain or other obstacles. For very low power beacons, the authorities may consider it not worth the trouble for enforcement; especially when they really don't cause harmful interference. Considering that the cost of a tiny micro-power beacon is so low, the creator can simply put another one (or two) on the air to replace it in a slightly different location... with an ensuing escalation of the beacon whack-a-mole game.

Here are some proposed definitions for a "Wild Beacon".

1. "A repetitive or continuous unauthorized pirate transmitter, with minimal content modulation, located in an area without permission."

2. "An unsupervised pirate transmitter beacon that is located in an open or not-authorized place."

Looking up the root definition of "wild", in various dictionaries, we see:
wild : adjective
  • (of an animal or plant) living or growing in the natural environment; not domesticated or cultivated.
    synonyms: untamed, undomesticated, feral
  • uncontrolled or unrestrained, especially in pursuit of pleasure.
  • not subject to restraint or regulation
    synonyms: uncontrolled, unrestrained, out of control, undisciplined, unruly, rowdy, disorderly, riotous
  • characteristic of, appropriate to, or expressive of wilderness, wildlife, or a simple or uncivilized society

wild : noun
  • a natural state or uncultivated or uninhabited region.
    "kiwis are virtually extinct in the wild"

Other possible names  :D  Feral Beacon, Beacon In The Wild, Beacons Gone Wild, Homeless Beacon, Rough Beacon

Pirate Radio History / Radio Caroline
« on: August 28, 2018, 2205 UTC »
While in Liverpool on business in late 1979 into early 1980, I was invited to attend a fund-raising disco dance party for Radio Caroline.
I met some fascinating Radio Caroline staff and supporters there.
They gave me some Radio Caroline promotional items, which I later shared with friends.

My only surviving item from that event is a sticker, on a trusty old toolbox which has served me well around the world several times since then.

Purely for historical reference purposes, I'm posting a photo and information about the Radio Caroline sticker here.

Radio Caroline sticker. Photo date: 28 August 2018.
Photo description: Radio Caroline sticker, circa 1979-1980, on Craftsman metal toolbox; also WRNO Worldwide (shortwave broadcaster) sticker, circa 1980.
Sticker description: Round circle, diameter 5.5 inches (100mm) , white vinyl with black print, glossy.
Printed black image on white background sticker: Centre, silhouette line art of the Radio Caroline vessel " Mi Amigo " and text "ON 319 METRES"; Top text: "RADIO CAROLINE"; Bottom text: "ALBUM TRACKS FROM THE NORTH SEA" "PRODUCED BY FRS ENGLAND PO BOX 123 READING RG3 5JU"

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