Interference on HF

[♠SARKID♠]

Did anybody else hear the illegal traffic on NA this evening?  Happened around 23:05Z, a couple of non CAP guys talking about whatever.  I already made a report to my DC (with a recording), wanted to know if anybody else heard them.

[JoeTomasone]

On Saturday night around the same time (2300-0000Z) I heard extensive chatter a few khz higher that was too long to be legitimate, but it was too weak to be intelligible.   This is not surprising since we were using a homemade 1/4 wave inverted V dipole at about 25 feet.      Might be the same people?   Perhaps tonight I will have a listen and see what I can hear.   

[♠SARKID♠]

Possible; keep your ears open.  Its times like this I wish I had an HF receiver or better yet transceiver for at home.

[PHall]

That frequency is fairly near an AIRINC frequency used by transoceanic flights across the Atlantic.
And the time you heard it is about right for that frequency to be in use too.
And most airliners have HF transceivers that put out 1000 watts of power.

[♠SARKID♠]

That frequency is fairly near an AIRINC frequency used by transoceanic flights across the Atlantic.
And the time you heard it is about right for that frequency to be in use too.
And most airliners have HF transceivers that put out 1000 watts of power.

This was no airliner traffic.  After listening hard as I could to my recording, I realized that its a couple of sailors/fishermen talking about their boats and crews.  And the quality is way too clear to be bleedover or USB/LSB confliction IMHO.

Here's the recording I made
http://resdon111.googlepages.com/interference.wma

[JoeTomasone]

They don't appear to be hams, and that's no harmonic.

[♠SARKID♠]

They don't appear to be hams, and that's no harmonic.

I listened for about five or ten minutes prior to making the recording and there was no callsigns used of any kind.

[PHall]

They don't appear to be hams, and that's no harmonic.

I listened for about five or ten minutes prior to making the recording and there was no callsigns used of any kind.

If it is fishermen then good luck busting them!

[SarDragon]

That frequency is fairly near an AIRINC frequency used by transoceanic flights across the Atlantic.
And the time you heard it is about right for that frequency to be in use too.
And most airliners have HF transceivers that put out 1000 watts of power.

Where do they hide the antennas?

[desertengineer1]

They don't appear to be hams, and that's no harmonic.

I listened for about five or ten minutes prior to making the recording and there was no callsigns used of any kind.

If it is fishermen then good luck busting them!

This is pretty common with mariners.  Yeah, the laws forbid the activity, but no one cares.  If they can't stop tons of heroin or trailers of sex slaves pouring into the country, I doubt anyone cares about these guys using an unauthorized frequency.

If they are in rough seas, alone, and at night, it helps to have contact with another ship if there are no other options than HF.  They could be bored as heck and are trying to stay awake.

Maybe you could catch them downloading copyrighted music?  That would send the feds after them for sure 

Your choice is to Jam them with 10,000 watts to make them go elsewhere or go to another frequency.  Obviously, we can't do the former.  Make sure you fill out and submit the interference report per the regs.  At the least, we'll get good visibility our members are more proactive in HF.

Most string up a wire antenna from the mast top down, or have a tuned whip antenna.  Propagation is excellent because they have the best ground plane on the planet.  They could be anywhere.

[desertengineer1]

That frequency is fairly near an AIRINC frequency used by transoceanic flights across the Atlantic.
And the time you heard it is about right for that frequency to be in use too.
And most airliners have HF transceivers that put out 1000 watts of power.

Where do they hide the antennas?

Most modern airliners have strip antennas along an edge.  Military aircraft like the C-130 have wire antennas from the centerline up to the tail fed with 400W.

1000 Watts is a bit high.  The ARC-190 series does 400 Watts into a tuned wire antenna.  Power higher than that is unusual because of arcing (equipment damage) and the excessive weight (biggest reason).  Lower atmospheric pressure = lower breakdown voltage = arcing and corona.

[JoeTomasone]

This is pretty common with mariners.  Yeah, the laws forbid the activity, but no one cares.  If they can't stop tons of heroin or trailers of sex slaves pouring into the country, I doubt anyone cares about these guys using an unauthorized frequency.

Ah, Grasshopper, you obviously are not very familiar with the FCC...   They can DF on HF from remote monitoring stations and then call in the local boys to finish off the job.   (Not terribly different from how ELTs get found, come to that!).    Cadet Turkal's DC should take that recording and contact the FCC.   

[desertengineer1]

Ah, Grasshopper, you obviously are not very familiar with the FCC...   They can DF on HF from remote monitoring stations and then call in the local boys to finish off the job.   (Not terribly different from how ELTs get found, come to that!).    Cadet Turkal's DC should take that recording and contact the FCC.   

LOL!  So they take the time away from high priority DFing to get a bearing on these guys.  One turns out to be somewhere in the North Atlantic 400 nm East of New Jersey (in international waters).  The other about 300 nm Southeast of that. 

There are thousands of ships out there on any given day.  Most of those are under way at 15+ knots.  Many more anchored in clusters awaiting sequenced entry. 

[♠SARKID♠]

Ah, Grasshopper, you obviously are not very familiar with the FCC...   They can DF on HF from remote monitoring stations and then call in the local boys to finish off the job.   (Not terribly different from how ELTs get found, come to that!).    Cadet Turkal's DC should take that recording and contact the FCC.   

LOL!  So they take the time away from high priority DFing to get a bearing on these guys.  One turns out to be somewhere in the North Atlantic 400 nm East of New Jersey (in international waters).  The other about 300 nm Southeast of that. 

There are thousands of ships out there on any given day.  Most of those are under way at 15+ knots.  Many more anchored in clusters awaiting sequenced entry. 

You're all also assuming that they aren't 20 miles away sitting in Lake Michigan.

[JoeTomasone]

LOL!  So they take the time away from high priority DFing to get a bearing on these guys. 

They DF unauthorized people in the ham, LMR, and marine bands routinely.  Trust me, they'll DF someone operating an unlicensed transmitter on Government frequencies.

[SarDragon]

That frequency is fairly near an AIRINC frequency used by transoceanic flights across the Atlantic.
And the time you heard it is about right for that frequency to be in use too.
And most airliners have HF transceivers that put out 1000 watts of power.

Where do they hide the antennas?

Most modern airliners have strip antennas along an edge.  Military aircraft like the C-130 have wire antennas from the centerline up to the tail fed with 400W.

1000 Watts is a bit high.  The ARC-190 series does 400 Watts into a tuned wire antenna.  Power higher than that is unusual because of arcing (equipment damage) and the excessive weight (biggest reason).  Lower atmospheric pressure = lower breakdown voltage = arcing and corona.

I know about military a/c - I've changed enough of them. The olde ARC-94/102 sets would put out 1 kW. There are two of the RTs in a local surplus store for $395 ea.

[PHall]

That frequency is fairly near an AIRINC frequency used by transoceanic flights across the Atlantic.
And the time you heard it is about right for that frequency to be in use too.
And most airliners have HF transceivers that put out 1000 watts of power.

Where do they hide the antennas?

Most modern airliners have strip antennas along an edge.  Military aircraft like the C-130 have wire antennas from the centerline up to the tail fed with 400W.

1000 Watts is a bit high.  The ARC-190 series does 400 Watts into a tuned wire antenna.  Power higher than that is unusual because of arcing (equipment damage) and the excessive weight (biggest reason).  Lower atmospheric pressure = lower breakdown voltage = arcing and corona.

The AN/ARC-190's in the KC-135's/C-141's/C-5's all put out 1000 watts at the antenna per the dash one.
And on all three of the above named aircraft the HF antenna is the "spike" at the top of the vertical stabilizer.

[SarDragon]

OK, even more important to have a properly operating tuner in the system. Thanks.

[desertengineer1]

The AN/ARC-190's in the KC-135's/C-141's/C-5's all put out 1000 watts at the antenna per the dash one.
And on all three of the above named aircraft the HF antenna is the "spike" at the top of the vertical stabilizer.

This is incorrect - unless a new amplifier or high power variant has been developed.
I know it's been a while since comm/nav school and when i worked on C-130 H2's, but I remember 400 Watts.

References I have still show 400 Watts.  Depending on the band and the drive amplifier stage output, you'll usually get around 300 - 400 Watts AM.

Maybe a linear is available as an option for the tactical mobile version?  Regardless, the R/T output is solid state 400W into the tuner.

Still have scars on my wrists R^2'ing tuners out of the cargo bay.  Frikken engineers...


Here's one reference: http://www.geocities.com/illuzion30/2a4x2/hf-fun.htm

1000W is pretty high for that coupler. 

[PHall]

The AN/ARC-190's in the KC-135's/C-141's/C-5's all put out 1000 watts at the antenna per the dash one.
And on all three of the above named aircraft the HF antenna is the "spike" at the top of the vertical stabilizer.

This is incorrect - unless a new amplifier or high power variant has been developed.
I know it's been a while since comm/nav school and when i worked on C-130 H2's, but I remember 400 Watts.

References I have still show 400 Watts.  Depending on the band and the drive amplifier stage output, you'll usually get around 300 - 400 Watts AM.

Maybe a linear is available as an option for the tactical mobile version?  Regardless, the R/T output is solid state 400W into the tuner.

Still have scars on my wrists R^2'ing tuners out of the cargo bay.  Frikken engineers...


Here's one reference: http://www.geocities.com/illuzion30/2a4x2/hf-fun.htm

1000W is pretty high for that coupler. 

Wouldn't be the first time that there is a disconnect between the dash one and the maintenance manuals.

[SarDragon]

Collins sez 400W here. Page (4 of 7).

[♠SARKID♠]

[desertengineer1]

Wouldn't be the first time that there is a disconnect between the dash one and the maintenance manuals.

You dare say that a -1 (or -5) would be incorrect?  Silence your blasphemy!  IMPOSSIBLE!

LOL!  OK, in all seriousness, are the boat bubbas still hanging around on the channel?

I've got automated recording software available - and an audio port in the remote control cable I built.  Can set it to monitor and record if needed.

[MIKE]

^^ Ditto. Lock.