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Author Topic: Bouvet 3Y0J  (Read 1776 times)

K1JX

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Re: Bouvet 3Y0J
« Reply #15 on: February 25, 2023, 10:37:55 AM »

I think there could be a solution to this jamming.  Or, at least, a partial one.

(Note: I don't claim to be the originator of this idea - only the first one to mention it in this thread.)

P59DX (14001 KHz): "CQ CQ DE P59DX P59DX UP"

Same as usual.  Except, P59DX answers his or her callers on *their* transmit frequency.  Frequency hopping spread spectrum on CW.

K1JX (14017 KHz):  "K1JX K1JX"

P59DX (14017 KHz):  "K1JX 339"

K1JX (14017 KHz): "TU 599"

P59DX (14017 KHz): "TU"

This requires no more work for the DX station.  It's still turning a single tuning knob, picking out callers, answering them, and putting them into log.  No extra transmissions.

For the callers, it's about the same amount of effort.  They still have to find the right place to call, using whatever patterns they discern.  In order to hear the DX and be heard, it encourages them to find a clear frequency, which they should be doing now anyway.

But, overall it uses bandwidth - already taken up by callers - to jump around the jammers.  It's much harder to jam a moving target.  No need for the UP cops.

I guess the same could be done on phone.

You could, and I am certain somebody will, argue that this might slow the rate down from the theoretical best that's possible from the current approach.  But, that's the rub, isn't it?  We can't get close to the theoretical best because of the associated crap slowing things down.

As for FT8, well, Fox and Hound operation is a great idea.  That assumes that everybody follows the "rules".  If somebody doesn't call above 1000 Hz, they won't be copied by the Fox.  But, they could also park themselves right on the Fox's frequency and jam every caller who gets moved there by the software to give a report to the Fox.  Their intent may not be to jam - they're just showing their ignorance.  But, the result is the same.

Some DXpeditioners have told me that the reason why they use MSHV instead of F/H is because of this.  If they copy me at 2344 Hz when I'm calling them, there's a good chance they'll copy my report or closing "RR" from that same frequency.

If everybody used wider filters for FT8 operation so that the effective band was wider, many of these problems would go away.  But, a lot of radios don't come equipped for using more than 2700 Hz or so receive bandwidth.  That gives about 2000 Hz for Hounds in F/H mode, and often not even that much.  In some radios, you can't even install a wider filter as an option.  That doesn't help.

Of course, an FT8 DX station could use the same frequency hopping idea as described above.  Answer on the caller's frequency.  That's already built into the software as a check box option.

Yeah, people would have to change some of their habits.  So?
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W2LO

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Re: Bouvet 3Y0J
« Reply #16 on: February 25, 2023, 10:56:57 AM »

This was an idea I had suggested on this forum in 2013. I'm sure it could be improved on by others and might be worth a try:
 
RE: Brainstorming: is there a better way for the DX to avoid QRM?
« Reply #2 on: June 08, 2013, 05:53:43 AM »
ReplyQuote
 A novel twist on the DX station avoiding pileup QRM happened a few years ago while I was listening to a DXpedition . Initially the DX station was listening up as usual but then he started to come back on the CALLERS' frequencies, hopping from spot to spot. The pileup took some time to figure out what was happening but eventually many stations got the idea.

 A method like that would make it difficult for an intentional QRMer to wreak havoc since even if he found the DX station the DX would have probably made a contact and moved somewhere else. For the QRMer the DX would be an elusive, moving target that never stays put; the legitimate caller has no problem. Everyone in the pileup would just park themselves somewhere knowing that the DX would come back transceive. There would be no "up" police, etc.

 I've thought about that day and what I heard. Maybe the idea has some merit but then how do you know if the DX has gone QRT, is asking for EU only, etc.? Perhaps the DX could start on a frequency, make the announcement he's going simplex on callers' frequencies and then come back to the original frequency for announcements.

 Maybe it's got the kernel of an idea but there are issues; how can you reliably hear a weak DX station amid perhaps three or four other callers close to your frequency, etc.

 Just a thought...

 
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KJ4Z

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Re: Bouvet 3Y0J
« Reply #17 on: February 25, 2023, 11:10:40 AM »

The "unsplit" proposal is interesting but there's a few concerns that occur to me.

Any competent DXer armed with modern tools (his ears, a panadapter, maybe CW skimmer etc) is going to be analyzing the pileup and using that to predict the DX operator's next frequency, just as he would do right now.  That means lots of big guns are going to descend on the next probable frequency, turning the pileup into a series of simplex pileups, effectively.  Instead of trying to hear through the DQRM, you would need to hear through all the other callers on your frequency.  Any systematic approach that the DX might take to overcome this problem is likely to be detected in a large enough pileup.  So if you wanted to avoid that outcome, the DX would need to ensure that his frequency selection is truly random.  And in that case, how satisfying would this be for the DX chaser?  I dunno about you, but I don't particularly enjoy a pileup where I park somewhere, call repeatedly and just hope.

It is an interesting idea though.

Edit: one other question: how do you know when the pileup is over?  You call and call and after awhile, you tune around and see if anyone else is still calling?  How do you prevent zombie pileups lasting hours after the DX already left?
« Last Edit: February 25, 2023, 11:27:12 AM by KJ4Z »
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OK4FX

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Re: Bouvet 3Y0J
« Reply #18 on: February 25, 2023, 11:26:57 AM »

I am afraid that in addition to the real dxpedition, pirates would also travel through pile up.
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Mira OK4FX

KJ4Z

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Re: Bouvet 3Y0J
« Reply #19 on: February 25, 2023, 11:28:10 AM »

I am afraid that in addition to the real dxpedition, pirates would also travel through pile up.

So simple.  So effective.  Brilliant.
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AA6YQ

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Re: Bouvet 3Y0J
« Reply #20 on: February 25, 2023, 11:59:47 AM »

Any competent DXer armed with modern tools (his ears, a panadapter, maybe CW skimmer etc) is going to be analyzing the pileup and using that to predict the DX operator's next frequency, just as he would do right now.  That means lots of big guns are going to descend on the next probable frequency, turning the pileup into a series of simplex pileups, effectively.

If a rare DX station operating split exhibits a pattern in his or her choice of "next listening frequency", knowledgeable DXers in pursuit will all be calling there - no matter where the DX station is going to respond with a callsign. Such DX stations would be better served to avoid any pattern, making their choice of "next listening frequency" as random as possible. The optimal strategy for DXers then becomes "find a hole in the split range and call there", which keeps the pursuers spread out across the range, eliminating pileups on a "next probable listening frequency".
« Last Edit: February 25, 2023, 12:03:57 PM by AA6YQ »
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KJ4Z

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Re: Bouvet 3Y0J
« Reply #21 on: February 25, 2023, 12:11:32 PM »

If a rare DX station operating split exhibits a pattern in his or her choice of "next listening frequency", knowledgeable DXers in pursuit will all be calling there - no matter where the DX station is going to respond with a callsign. Such DX stations would be better served to avoid any pattern, making their choice of "next listening frequency" as random as possible. The optimal strategy for DXers then becomes "find a hole in the split range and call there", which keeps the pursuers spread out across the range, eliminating pileups on a "next probable listening frequency".

Indeed, I already anticipated exactly this in my original post and commented that such a pileup would not be very satisfying to me, although perhaps trying to find some constantly moving hole in the pileup would provide some stimulation.

I still think OK4FX's observation about pirates is potentially fatal.  As many callers won't be hearing the DX on a routine basis, it will be harder for them to discern whether the station that just called them was real or not.  I still also don't understand how the pileup is controlled when there is no obvious central frequency for participants to listen to, to know whether the DX has gone QRT, etc.
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KD8MJR

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Re: Bouvet 3Y0J
« Reply #22 on: February 26, 2023, 12:13:16 PM »

I am afraid that in addition to the real dxpedition, pirates would also travel through pile up.

Yep that is what they would do.
One nice thing about SSB is that even a moderate level operator starts to learn the voices of the DXpedition SSB guys and it's easy to pick them out even during QRM and very hard to fake.  Plus since most of the DQRMers are regular Hams they get scared to even reveal their voice lest hams who know them realize who they are.

One thing that was very annoying with 3Y0J and FT8 was that when they were working NA the guys in the EU would start calling out to their needed DX using one of 3Y0J streams and thereby killing one of 3YOJ streams.

 The reverse would happen when the EU had good propagation, some US Hams would park on their Tx Freq and try to work a Dx in the EU that was calling 3Y0J.


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“A lie can travel half way around the world while the truth is putting on its shoes.”  (Mark Twain)

WO7R

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Re: Bouvet 3Y0J
« Reply #23 on: February 26, 2023, 01:06:56 PM »

Quote
Initially the DX station was listening up as usual but then he started to come back on the CALLERS' frequencies, hopping from spot to spot. The pileup took some time to figure out what was happening but eventually many stations got the idea.

In "The Complete DXer", W9KNI writes about this.  He suggests it is a very bad way, in the end, to manage a pileup.  And yes, he knew all about jammers "back then" -- they existed since forever.

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W6OU

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Re: Bouvet 3Y0J
« Reply #24 on: February 26, 2023, 10:49:09 PM »

If everybody used wider filters for FT8 operation so that the effective band was wider, many of these problems would go away.  But, a lot of radios don't come equipped for using more than 2700 Hz or so receive bandwidth.  That gives about 2000 Hz for Hounds in F/H mode, and often not even that much.  In some radios, you can't even install a wider filter as an option.  That doesn't help.

If the hound sets the Split Operation option to Fake It then he can transmit beyond his filter response.  WSJT-X will shift the transmit frequency upward and the FT8 audio signal downward to bring the signal into the filter bandpass.
« Last Edit: February 26, 2023, 10:53:12 PM by W6OU »
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K1JX

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Re: Bouvet 3Y0J
« Reply #25 on: February 27, 2023, 06:03:27 AM »

If the hound sets the Split Operation option to Fake It then he can transmit beyond his filter response.  WSJT-X will shift the transmit frequency upward and the FT8 audio signal downward to bring the signal into the filter bandpass.

Very true.  The DX station still needs a wider receive filter to hear the callers in the first place.  That puts the onus on the DX station, which isn't always a good idea.
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KB8GAE

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Re: Bouvet 3Y0J
« Reply #26 on: March 03, 2023, 10:07:25 AM »

Bouvet looks awesome on the 3Y0J QSL.

https://www.dx-world.net/qsl-preview-3y0j/

73 Rich KB8GAE
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KD8MJR

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Re: Bouvet 3Y0J
« Reply #27 on: March 03, 2023, 10:20:42 AM »

Bouvet looks awesome on the 3Y0J QSL.

https://www.dx-world.net/qsl-preview-3y0j/

73 Rich KB8GAE

This kind of brings back that previous question in the Main Thread.
If your an operator and did not get to land and work from Bouvet then are you still considered a part of the team?
Only 7 guys in the Photo and a I guess they had no tripod so the eight guy had to take the Photo.  If I was one of the other four I am pretty sure that  this card would not make me happy.  Maybe a photo without operators in it would have been a better fit.
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“A lie can travel half way around the world while the truth is putting on its shoes.”  (Mark Twain)

K1VSK

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Re: Bouvet 3Y0J
« Reply #28 on: March 03, 2023, 10:29:19 AM »




If your an operator and did not get to land and work from Bouvet then are you still considered a part of the team?


A whole bunch of players sat on the bench during the Super Bowl but they were still on the team.

Only one guy drives the car but the crew is still part of the NASCAR team.

Only one surgeon operates but there are a bunch of others on the surgical team.

See the trend?
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KD8MJR

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Re: Bouvet 3Y0J
« Reply #29 on: March 03, 2023, 01:12:31 PM »




If your an operator and did not get to land and work from Bouvet then are you still considered a part of the team?


A whole bunch of players sat on the bench during the Super Bowl but they were still on the team.

Only one guy drives the car but the crew is still part of the NASCAR team.

Only one surgeon operates but there are a bunch of others on the surgical team.

See the trend?

No not really!
Visalia 2023:  So what was it like to go and operate from Bouvet?
Operator:  Oh well i never went on the island I stayed on the boat!
Visalia:  Send the next Expedition Member please...
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“A lie can travel half way around the world while the truth is putting on its shoes.”  (Mark Twain)
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