Unidentified signals on FT8 frequencies Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern) Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?Identifying signals in the satellite exclusive bandDMR / DSTAR / P25 Software Encode / DecodeExpected practices for one ham operating under another's privileges?How do I go about identifying an unknown digital signal?Troposcatter: really all that bad?Is there an FT8 or other weak-signal digital mode specification available?How/where can I learn about ft8?What is the minimum equipment necessary to get on the air with FT8?What does CQ NM mean in FT8?Should I add call signs with /R suffix to the logbook?
Is it common practice to audition new musicians one-on-one before rehearsing with the entire band?
How can I use the Python library networkx from Mathematica?
An adverb for when you're not exaggerating
Withdrew £2800, but only £2000 shows as withdrawn on online banking; what are my obligations?
How do I find out the mythology and history of my Fortress?
2001: A Space Odyssey's use of the song "Daisy Bell" (Bicycle Built for Two); life imitates art or vice-versa?
Generate an RGB colour grid
Circuit to "zoom in" on mV fluctuations of a DC signal?
Delete nth line from bottom
Can anything be seen from the center of the Boötes void? How dark would it be?
Using et al. for a last / senior author rather than for a first author
Do wooden building fires get hotter than 600°C?
Is there any way for the UK Prime Minister to make a motion directly dependent on Government confidence?
Is the Standard Deduction better than Itemized when both are the same amount?
How to react to hostile behavior from a senior developer?
Do square wave exist?
Is there a kind of relay only consumes power when switching?
Can an alien society believe that their star system is the universe?
How come Sam didn't become Lord of Horn Hill?
How would a mousetrap for use in space work?
Is CEO the profession with the most psychopaths?
Do jazz musicians improvise on the parent scale in addition to the chord-scales?
Is it a good idea to use CNN to classify 1D signal?
Maximum summed powersets with non-adjacent items
Unidentified signals on FT8 frequencies
Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)
Announcing the arrival of Valued Associate #679: Cesar Manara
Unicorn Meta Zoo #1: Why another podcast?Identifying signals in the satellite exclusive bandDMR / DSTAR / P25 Software Encode / DecodeExpected practices for one ham operating under another's privileges?How do I go about identifying an unknown digital signal?Troposcatter: really all that bad?Is there an FT8 or other weak-signal digital mode specification available?How/where can I learn about ft8?What is the minimum equipment necessary to get on the air with FT8?What does CQ NM mean in FT8?Should I add call signs with /R suffix to the logbook?
$begingroup$
When I work in FT8 mode I often see signals like these:
I couldn't identify these signals using SigiWiki nor managed I to decode them using WSJT-X. Though these signals seem to use 15 second frames. They don't seem to be a noise created by stations that use too much power.
Does it look like any amateur radio digital mode to you?
digital-modes signal-identification ft8
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
$endgroup$
add a comment |
$begingroup$
When I work in FT8 mode I often see signals like these:
I couldn't identify these signals using SigiWiki nor managed I to decode them using WSJT-X. Though these signals seem to use 15 second frames. They don't seem to be a noise created by stations that use too much power.
Does it look like any amateur radio digital mode to you?
digital-modes signal-identification ft8
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
$endgroup$
2
$begingroup$
It would be helpful if the frequency scale was shown in order to understand the bandwidth of the signal components.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:14
1
$begingroup$
Also notice that the left and right marked signals are different schemes. They are both 8-MFSK but they are using different tones/bandwidths.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:32
$begingroup$
The frequency is 14.074. One mark on the top is 100 Hz.
$endgroup$
– Aleksander Alekseev - R2AUK
Mar 8 at 16:58
add a comment |
$begingroup$
When I work in FT8 mode I often see signals like these:
I couldn't identify these signals using SigiWiki nor managed I to decode them using WSJT-X. Though these signals seem to use 15 second frames. They don't seem to be a noise created by stations that use too much power.
Does it look like any amateur radio digital mode to you?
digital-modes signal-identification ft8
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
$endgroup$
When I work in FT8 mode I often see signals like these:
I couldn't identify these signals using SigiWiki nor managed I to decode them using WSJT-X. Though these signals seem to use 15 second frames. They don't seem to be a noise created by stations that use too much power.
Does it look like any amateur radio digital mode to you?
digital-modes signal-identification ft8
digital-modes signal-identification ft8
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
asked Mar 8 at 15:03
Aleksander Alekseev - R2AUKAleksander Alekseev - R2AUK
82910
82910
2
$begingroup$
It would be helpful if the frequency scale was shown in order to understand the bandwidth of the signal components.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:14
1
$begingroup$
Also notice that the left and right marked signals are different schemes. They are both 8-MFSK but they are using different tones/bandwidths.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:32
$begingroup$
The frequency is 14.074. One mark on the top is 100 Hz.
$endgroup$
– Aleksander Alekseev - R2AUK
Mar 8 at 16:58
add a comment |
2
$begingroup$
It would be helpful if the frequency scale was shown in order to understand the bandwidth of the signal components.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:14
1
$begingroup$
Also notice that the left and right marked signals are different schemes. They are both 8-MFSK but they are using different tones/bandwidths.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:32
$begingroup$
The frequency is 14.074. One mark on the top is 100 Hz.
$endgroup$
– Aleksander Alekseev - R2AUK
Mar 8 at 16:58
2
2
$begingroup$
It would be helpful if the frequency scale was shown in order to understand the bandwidth of the signal components.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:14
$begingroup$
It would be helpful if the frequency scale was shown in order to understand the bandwidth of the signal components.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:14
1
1
$begingroup$
Also notice that the left and right marked signals are different schemes. They are both 8-MFSK but they are using different tones/bandwidths.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:32
$begingroup$
Also notice that the left and right marked signals are different schemes. They are both 8-MFSK but they are using different tones/bandwidths.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:32
$begingroup$
The frequency is 14.074. One mark on the top is 100 Hz.
$endgroup$
– Aleksander Alekseev - R2AUK
Mar 8 at 16:58
$begingroup$
The frequency is 14.074. One mark on the top is 100 Hz.
$endgroup$
– Aleksander Alekseev - R2AUK
Mar 8 at 16:58
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
The fact that they align properly to the FT8 15-second period, and have 8 tones (the same as FT8) is a sign that these may be distorted FT8 signals, caused by AF harmonics in the transmitter or the receiver. The one on the right, being about 100Hz wide, is a second harmonic, and the one on the left, being about 150Hz wide, may be a third harmonic.
But before you go looking for the offending signal at 1/2 or 1/3 of the audio frequency, remember that when the "Split" option in wsjtx is set to "Rig" or "Fake It", the software will adjust the TX VFO in order to put the transmit audio somewhere between 1500 and 2000 Hz. e.g. if you're on 14.074.000 and you put your transmit cursor on 235Hz, wsjtx will actually tune the rig to 14.072.500 and send it audio at 1735Hz; if you put your transmit cursor on 2560Hz, wsjtx will tune the rig to 14.075.000 and send it audio at 1560Hz. If the distortion is being caused by the transmitter, therefore, the subharmonic will probably not appear on the waterfall at 1/2 or 1/3 of the frequency of the harmonic product.
Even with this offsetting, a third harmonic anywhere to the left of 3000Hz on the waterfall is hard to explain, but it may be caused by frequency aliasing in the receive path. Perhaps someone else has a more complete explanation.
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
$endgroup$
$begingroup$
I think you're right. The FT8 signal level from the sound card to the rig's mic input may be too high, or the operator may have his mic gain up too high.
$endgroup$
– Mike Waters♦
Mar 8 at 21:41
add a comment |
$begingroup$
Both marked signals follow an 8 tone MFSK pattern. The one on the left is about 125 hertz wide while the one on the right is about 100 hertz wide.
The signal on the left appears to follow the waterfall that would be expected from an Olivia 8/125 (8 tones with 125 hertz bandwidth) signal although this is not a common Olivia mode. Olivia is a free typing, teletype like mode, so the 15 second sequence wouldn't apply.
I cannot offer any suggestions for the 100 hertz wide signal on the right of the waterfall.
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
$endgroup$
add a comment |
Your Answer
StackExchange.ifUsing("editor", function ()
return StackExchange.using("schematics", function ()
StackExchange.schematics.init();
);
, "cicuitlab");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "520"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fham.stackexchange.com%2fquestions%2f12976%2funidentified-signals-on-ft8-frequencies%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
The fact that they align properly to the FT8 15-second period, and have 8 tones (the same as FT8) is a sign that these may be distorted FT8 signals, caused by AF harmonics in the transmitter or the receiver. The one on the right, being about 100Hz wide, is a second harmonic, and the one on the left, being about 150Hz wide, may be a third harmonic.
But before you go looking for the offending signal at 1/2 or 1/3 of the audio frequency, remember that when the "Split" option in wsjtx is set to "Rig" or "Fake It", the software will adjust the TX VFO in order to put the transmit audio somewhere between 1500 and 2000 Hz. e.g. if you're on 14.074.000 and you put your transmit cursor on 235Hz, wsjtx will actually tune the rig to 14.072.500 and send it audio at 1735Hz; if you put your transmit cursor on 2560Hz, wsjtx will tune the rig to 14.075.000 and send it audio at 1560Hz. If the distortion is being caused by the transmitter, therefore, the subharmonic will probably not appear on the waterfall at 1/2 or 1/3 of the frequency of the harmonic product.
Even with this offsetting, a third harmonic anywhere to the left of 3000Hz on the waterfall is hard to explain, but it may be caused by frequency aliasing in the receive path. Perhaps someone else has a more complete explanation.
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
$endgroup$
$begingroup$
I think you're right. The FT8 signal level from the sound card to the rig's mic input may be too high, or the operator may have his mic gain up too high.
$endgroup$
– Mike Waters♦
Mar 8 at 21:41
add a comment |
$begingroup$
The fact that they align properly to the FT8 15-second period, and have 8 tones (the same as FT8) is a sign that these may be distorted FT8 signals, caused by AF harmonics in the transmitter or the receiver. The one on the right, being about 100Hz wide, is a second harmonic, and the one on the left, being about 150Hz wide, may be a third harmonic.
But before you go looking for the offending signal at 1/2 or 1/3 of the audio frequency, remember that when the "Split" option in wsjtx is set to "Rig" or "Fake It", the software will adjust the TX VFO in order to put the transmit audio somewhere between 1500 and 2000 Hz. e.g. if you're on 14.074.000 and you put your transmit cursor on 235Hz, wsjtx will actually tune the rig to 14.072.500 and send it audio at 1735Hz; if you put your transmit cursor on 2560Hz, wsjtx will tune the rig to 14.075.000 and send it audio at 1560Hz. If the distortion is being caused by the transmitter, therefore, the subharmonic will probably not appear on the waterfall at 1/2 or 1/3 of the frequency of the harmonic product.
Even with this offsetting, a third harmonic anywhere to the left of 3000Hz on the waterfall is hard to explain, but it may be caused by frequency aliasing in the receive path. Perhaps someone else has a more complete explanation.
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
$endgroup$
$begingroup$
I think you're right. The FT8 signal level from the sound card to the rig's mic input may be too high, or the operator may have his mic gain up too high.
$endgroup$
– Mike Waters♦
Mar 8 at 21:41
add a comment |
$begingroup$
The fact that they align properly to the FT8 15-second period, and have 8 tones (the same as FT8) is a sign that these may be distorted FT8 signals, caused by AF harmonics in the transmitter or the receiver. The one on the right, being about 100Hz wide, is a second harmonic, and the one on the left, being about 150Hz wide, may be a third harmonic.
But before you go looking for the offending signal at 1/2 or 1/3 of the audio frequency, remember that when the "Split" option in wsjtx is set to "Rig" or "Fake It", the software will adjust the TX VFO in order to put the transmit audio somewhere between 1500 and 2000 Hz. e.g. if you're on 14.074.000 and you put your transmit cursor on 235Hz, wsjtx will actually tune the rig to 14.072.500 and send it audio at 1735Hz; if you put your transmit cursor on 2560Hz, wsjtx will tune the rig to 14.075.000 and send it audio at 1560Hz. If the distortion is being caused by the transmitter, therefore, the subharmonic will probably not appear on the waterfall at 1/2 or 1/3 of the frequency of the harmonic product.
Even with this offsetting, a third harmonic anywhere to the left of 3000Hz on the waterfall is hard to explain, but it may be caused by frequency aliasing in the receive path. Perhaps someone else has a more complete explanation.
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
$endgroup$
The fact that they align properly to the FT8 15-second period, and have 8 tones (the same as FT8) is a sign that these may be distorted FT8 signals, caused by AF harmonics in the transmitter or the receiver. The one on the right, being about 100Hz wide, is a second harmonic, and the one on the left, being about 150Hz wide, may be a third harmonic.
But before you go looking for the offending signal at 1/2 or 1/3 of the audio frequency, remember that when the "Split" option in wsjtx is set to "Rig" or "Fake It", the software will adjust the TX VFO in order to put the transmit audio somewhere between 1500 and 2000 Hz. e.g. if you're on 14.074.000 and you put your transmit cursor on 235Hz, wsjtx will actually tune the rig to 14.072.500 and send it audio at 1735Hz; if you put your transmit cursor on 2560Hz, wsjtx will tune the rig to 14.075.000 and send it audio at 1560Hz. If the distortion is being caused by the transmitter, therefore, the subharmonic will probably not appear on the waterfall at 1/2 or 1/3 of the frequency of the harmonic product.
Even with this offsetting, a third harmonic anywhere to the left of 3000Hz on the waterfall is hard to explain, but it may be caused by frequency aliasing in the receive path. Perhaps someone else has a more complete explanation.
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
answered Mar 8 at 21:08
hobbs - KC2Ghobbs - KC2G
99228
99228
$begingroup$
I think you're right. The FT8 signal level from the sound card to the rig's mic input may be too high, or the operator may have his mic gain up too high.
$endgroup$
– Mike Waters♦
Mar 8 at 21:41
add a comment |
$begingroup$
I think you're right. The FT8 signal level from the sound card to the rig's mic input may be too high, or the operator may have his mic gain up too high.
$endgroup$
– Mike Waters♦
Mar 8 at 21:41
$begingroup$
I think you're right. The FT8 signal level from the sound card to the rig's mic input may be too high, or the operator may have his mic gain up too high.
$endgroup$
– Mike Waters♦
Mar 8 at 21:41
$begingroup$
I think you're right. The FT8 signal level from the sound card to the rig's mic input may be too high, or the operator may have his mic gain up too high.
$endgroup$
– Mike Waters♦
Mar 8 at 21:41
add a comment |
$begingroup$
Both marked signals follow an 8 tone MFSK pattern. The one on the left is about 125 hertz wide while the one on the right is about 100 hertz wide.
The signal on the left appears to follow the waterfall that would be expected from an Olivia 8/125 (8 tones with 125 hertz bandwidth) signal although this is not a common Olivia mode. Olivia is a free typing, teletype like mode, so the 15 second sequence wouldn't apply.
I cannot offer any suggestions for the 100 hertz wide signal on the right of the waterfall.
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
$endgroup$
add a comment |
$begingroup$
Both marked signals follow an 8 tone MFSK pattern. The one on the left is about 125 hertz wide while the one on the right is about 100 hertz wide.
The signal on the left appears to follow the waterfall that would be expected from an Olivia 8/125 (8 tones with 125 hertz bandwidth) signal although this is not a common Olivia mode. Olivia is a free typing, teletype like mode, so the 15 second sequence wouldn't apply.
I cannot offer any suggestions for the 100 hertz wide signal on the right of the waterfall.
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
$endgroup$
add a comment |
$begingroup$
Both marked signals follow an 8 tone MFSK pattern. The one on the left is about 125 hertz wide while the one on the right is about 100 hertz wide.
The signal on the left appears to follow the waterfall that would be expected from an Olivia 8/125 (8 tones with 125 hertz bandwidth) signal although this is not a common Olivia mode. Olivia is a free typing, teletype like mode, so the 15 second sequence wouldn't apply.
I cannot offer any suggestions for the 100 hertz wide signal on the right of the waterfall.
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
$endgroup$
Both marked signals follow an 8 tone MFSK pattern. The one on the left is about 125 hertz wide while the one on the right is about 100 hertz wide.
The signal on the left appears to follow the waterfall that would be expected from an Olivia 8/125 (8 tones with 125 hertz bandwidth) signal although this is not a common Olivia mode. Olivia is a free typing, teletype like mode, so the 15 second sequence wouldn't apply.
I cannot offer any suggestions for the 100 hertz wide signal on the right of the waterfall.
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
answered Mar 8 at 17:59
Glenn W9IQGlenn W9IQ
16.9k11349
16.9k11349
add a comment |
add a comment |
Thanks for contributing an answer to Amateur Radio Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fham.stackexchange.com%2fquestions%2f12976%2funidentified-signals-on-ft8-frequencies%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
2
$begingroup$
It would be helpful if the frequency scale was shown in order to understand the bandwidth of the signal components.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:14
1
$begingroup$
Also notice that the left and right marked signals are different schemes. They are both 8-MFSK but they are using different tones/bandwidths.
$endgroup$
– Glenn W9IQ
Mar 8 at 16:32
$begingroup$
The frequency is 14.074. One mark on the top is 100 Hz.
$endgroup$
– Aleksander Alekseev - R2AUK
Mar 8 at 16:58