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Old 02-15-2017, 10:10 AM   #31
johndallman
 
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Default Re: Coast Guard response to distress call on Jewell Island, ME

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Originally Posted by Icelander View Post
I was wondering about that. O'Toole's player is an electric engineer (and a software engineer) and he didn't seem very confident that there were any settings on a hand-held radio like that to get any useful directional data.
It's simpler than that. The antenna on that Motorola looks to be a dipole or monopole, which means that it's least sensitive along the line of the antenna. So, turn the gain down until the jammer is just a strong signal, not saturating the receiver, tilt the radio 90 degrees so the antenna is horizontal and then turn around spotting the directions in which the received noise is at a maximum and a minimum.

The jammer is in one of the minimum directions, but you'll have to triangulate to find out which one. See Enhanced Senses, p10, for Triangulation rules.

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It is an option. It opens up directly into the sea, however, and during in-character discussion, Taylor claimed that the Atlantic in February would kill us before we could reach shore.
He's likely right. However, coming out of the sea onto Jewell Island, somewhere out of line-of-sight of the guard towers, gets you further from the jammer.
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Old 02-15-2017, 10:41 AM   #32
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Default Re: Coast Guard response to distress call on Jewell Island, ME

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Originally Posted by johndallman View Post
It's simpler than that. The antenna on that Motorola looks to be a dipole or monopole, which means that it's least sensitive along the line of the antenna. So, turn the gain down until the jammer is just a strong signal, not saturating the receiver, tilt the radio 90 degrees so the antenna is horizontal and then turn around spotting the directions in which the received noise is at a maximum and a minimum.

The jammer is in one of the minimum directions, but you'll have to triangulate to find out which one. See Enhanced Senses, p10, for Triangulation rules.
Magic!

Would this be merely a technical task of ordinary IQ-based Electronics Operation (Communications) or is there a chance that Per could help with it?

I mean, is there any relevant information to be gained from superior auditory reception and analysis of the static itself?

In related traits, Taylor has got Per 20, Parabolic Hearing 1 and Perks of hearing slightly lower and higher frequencies than humans ordinarily do.

Unfortunately, he doesn't have Discriminatory Hearing yet, but it certainly going to be the first new power he demonstrates, as he's been trying his best to use skill checks to analyse various sounds he's heard to build up a tactical picture.

If there's any way to justify using Per-based Electronics Operation (Communications), he'd certainly be a lot better at it than IQ-based. Even if only for a supporting roll giving a bonus to O'Toole.

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He's likely right. However, coming out of the sea onto Jewell Island, somewhere out of line-of-sight of the guard towers, gets you further from the jammer.
One tower has got a direct line-of-sight toward the place where the sewage pipe probably empties out, if anyone cares to look in that direction from it. Taylor estimates that it would take a pretty inept OpFor not to rate escape via the sewers as our most probable plan, as they lost us when we fled into the tunnel levels and most alternate routes involve either going outside where it's easy to spot us or past areas where the guards might have sealed off doors and/or set up ambushes.
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Old 02-15-2017, 11:41 AM   #33
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Default Re: Coast Guard response to distress call on Jewell Island, ME

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Originally Posted by Icelander View Post
Would this be merely a technical task of ordinary IQ-based Electronics Operation (Communications) or is there a chance that Per could help with it?

I mean, is there any relevant information to be gained from superior auditory reception and analysis of the static itself?
If the jammer were a perfect white noise source, there wouldn't be. But no finite machine is perfect, and the noise won't be perfectly distributed, although it shouldn't be pink noise either.

So what you need to do to use Per is work through the radio's frequency bands and find the one where you get the best directionality out of the antenna. This is likely to be the band where you're getting the least reflection off the structure of the building. This gives you an excuse for a complementary Per roll to the E/Ops (Comms) roll, at the cost of some extra time.
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Old 02-15-2017, 12:01 PM   #34
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Default Re: Coast Guard response to distress call on Jewell Island, ME

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If the jammer were a perfect white noise source, there wouldn't be. But no finite machine is perfect, and the noise won't be perfectly distributed, although it shouldn't be pink noise either.

So what you need to do to use Per is work through the radio's frequency bands and find the one where you get the best directionality out of the antenna. This is likely to be the band where you're getting the least reflection off the structure of the building. This gives you an excuse for a complementary Per roll to the E/Ops (Comms) roll, at the cost of some extra time.
We have time. We stopped last session as O'Toole was carefully trying to spoof the electronic device which would turn on an indicator light in the Warden's office if the armoury door is opened. That is likely to take him some time.

Taylor can play around with the radio he picked up from the last guard he subdued. Maybe even roll against Per-based Electronic Operations (Communications), as he does have the skill, at least, and hope to have some data points to present to O'Toole once he finishes, good for a bonus to his skill.

Looks like Dr. Anderson won't have much to contribute. He technically has skill 12 at Electronics Operation (Communications) from default, but that won't include familiarity at triangulation or even basic familiarity with the radio in question. Wait, he does have something to contribute, he has Area Knowledge (Manhanock Asylum for the Criminally Insane) at skill 16 from when he used to work here! He'll interpret our directional and distance data into a guess as to where in the complex the jammer is.

Hmmm... though I had planned to use the time while O'Toole is working on the security system to have a heart to heart conversation with him, complimenting him on his performance and good sense so far and so on. It is traditional to use brief lulls in the action to showcase budding relationships, of whatever kind, among the heroes and with a firm eye toward that tradition, Taylor is Chummy, interested in making friends with those he spends time with and prone to making embarrassingly earnest declarations of fraternity and friendship at the least provocation.

Maybe Taylor should toss Col. Burr the handheld instead, asking him if he can figure out where the jamming is coming from. At worst, he can't. At best, it would utilise the skills of an NPC who clearly must have some area of impressive skill to be a full Colonel of US Army Counterintelligence who is trusted with liaison work to Onyx Rain, serve to make Col. Burr feel useful and make him less likely to focus on brooding on his suspicions of sweet little Sherilyn.
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Old 02-16-2017, 08:01 AM   #35
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Default Detection and analysis of jamming by the Coast Guard

I'm trying to find some guidelines on how easy it is to detect jamming from a distance outside the range of the jammer.

The South Portland Coast Guard Station at 259 High Street, South Portland, ME 04106, is exactly 8 miles away from the approximate center of a 500-yd circle drawn around the Manhanock Asylum for the Criminally Insane complex on Jewell Island. I'm pretty sure that the Command Center for search and rescue, homeland security, pollution, law enforcement, and fisheries incidents involving the local maritime community is located at that site. That would mean computers and communications, as well as a staff on duty manning it 24/7.

It appears that the 249 High Street base also contains part of the USCG Sector Northern New England headquarters, though there are two buildings further away from Jewell Island, in Portland and closer to the airport in South Portland, that also belong to the Coast Guard. It may be that some of the investigative aspects of the mission are centered in the buildings near the airport and central Portland, rather than at the docks in South Portland. On the other hand, those may just be housing for unmarried Coasties and/or the Coast Guard Exchange.

So, with communication equipment for a Secter Command Center, what does the Coast Guard detect from 8 miles away?

Can they recognise deliberate white noise radio jamming on all frequencies from that distance, even if that jamming is not supposed to affect an area larger than several hundred yards in diameter? Determine something about the type of jammer?

Would they gain any more information from a cutter at a mile or two or a helicopter than they are getting from their Command Center at eight miles?
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Old 02-16-2017, 08:55 AM   #36
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Default Re: Detection and analysis of jamming by the Coast Guard

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Can they recognise deliberate white noise radio jamming on all frequencies from that distance, even if that jamming is not supposed to affect an area larger than several hundred yards in diameter? Determine something about the type of jammer?
Oh, good point. They can certainly detect that something odd is going on. Per High-Tech p212, using communications equipment within 10x the range of the jammer requires an unopposed skill roll.

That's an approximation, because a white-noise jammer is simply a transmitter broadcasting white noise, and the strength of the jamming signal with distance follows an inverse square law. The "range" of the jammer is a game abstraction, since there is no way within physics to make its effects stop at a given range. The quoted range is probably simply the maximum distance at which it will saturate the input of an "ordinary" receiver, or when added to a transmitter's output, exceed the transmitter's output all of the time.

The Coast Guard base is 8 miles away, about 25 times the jamming radius, and only 2.5x the range at which a skill roll is needed. I'd reckon a noise jammer is detectable at least 10x the range where you need a skill roll, probably much more. Selective jammers could be much less detectable, but are also easier to work around.
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Would they gain any more information from a cutter at a mile or two or a helicopter than they are getting from their Command Center at eight miles?
That depends on what equipment the vehicles have mounted. The command center should have directional aerials, either phased-array or moveable, and will thus be able to get the rough direction of the jamming. Since they had a call that claimed to be from Jewell Island, and that's in the direction of the jamming, the credibility of that call went up noticeably once they noticed the jamming. Sending a helicopter to get a cross-bearing on the jamming to confirm it is from Jewell Island won't take long. Then it's time for the Warden to answer difficult questions, or things get exciting.
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Old 02-16-2017, 09:09 AM   #37
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Default Re: Detection and analysis of jamming by the Coast Guard

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Originally Posted by johndallman View Post
The Coast Guard base is 8 miles away, about 25 times the jamming radius, and only 2.5x the range at which a skill roll is needed. I'd reckon a noise jammer is detectable at least 10x the range where you need a skill roll, probably much more. Selective jammers could be much less detectable, but are also easier to work around.
That's about what I reckoned.

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That depends on what equipment the vehicles have mounted. The command center should have directional aerials, either phased-array or moveable, and will thus be able to get the rough direction of the jamming. Since they had a call that claimed to be from Jewell Island, and that's in the direction of the jamming, the credibility of that call went up noticeably once they noticed the jamming. Sending a helicopter to get a cross-bearing on the jamming to confirm it is from Jewell Island won't take long. Then it's time for the Warden to answer difficult questions, or things get exciting.
Sounds right.

Here is a pretty good overview of what the USCG Northern New England Sector has.

The helicopters appear to be all located at Cape Cod. Would it be quicker to spin up one from there and fly 60 miles or man a 47' MLB or a 25' Defender class boat to motor eight miles and check things out?

For that matter, the USCGC Jefferson Island (WPB 1340), a 110' Island-class patrol boat has a home berth in South Portland. If it's not away on patrol somewhere hours off, it might be available to scoot over to the island. In addition to two M2 machine-guns, it comes with a 25mm autocannon, so it's properly armed. I don't know what the radio equipment is or whether it would add to their data.

Thales HF medium-powered, High-Frequency Automated Link Establishment (HF-ALE) radio communications system tell you anything about the communication capabilities on their cutters?

Or this list of USCG technological projects?
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Old 02-16-2017, 09:48 AM   #38
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Default Re: Detection and analysis of jamming by the Coast Guard

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The helicopters appear to be all located at Cape Cod. Would it be quicker to spin up one from there and fly 60 miles or man a 47' MLB or a 25' Defender class boat to motor eight miles and check things out?
The timescales are probably similar, but the chopper makes it much faster to find out where the jamming is coming from if it isn't Jewell Island. The Coast Guard will regard that jamming as a real problem, because it means people can't make ordinary distress calls. And jammers mean a military or terrorism operation, and they haven't been told about any military operations, so...
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For that matter, the USCGC Jefferson Island (WPB 1340), a 110' Island-class patrol boat has a home berth in South Portland. If it's not away on patrol somewhere hours off, it might be available to scoot over to the island. In addition to two M2 machine-guns, it comes with a 25mm autocannon, so it's properly armed.
Find out where it is, give them a heads-up, and get crews together for those boats, too.
Quote:
Thales HF medium-powered, High-Frequency Automated Link Establishment (HF-ALE) radio communications system tell you anything about the communication capabilities on their cutters?
It's a pretty good long-range radio system, and may be powerful enough to cut the effective range of that jammer, if they turn off the Automatic Link Establishment, which the jammer will be upsetting.
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Or this list of USCG technological projects?
Not from that - that's a web page from their PR department.
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Old 02-17-2017, 08:54 AM   #39
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Default Re: Detection and analysis of jamming by the Coast Guard

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Originally Posted by johndallman View Post
The timescales are probably similar, but the chopper makes it much faster to find out where the jamming is coming from if it isn't Jewell Island. The Coast Guard will regard that jamming as a real problem, because it means people can't make ordinary distress calls. And jammers mean a military or terrorism operation, and they haven't been told about any military operations, so...
I found that there are two 47' MLBs in South Portland and one of them is always kept ready for instant response, usually for a life-saving operation. There is also a 25' Defender B-class RB-S at the ready, with a watch-standing crew.

I found a case where the boats beat a helicopter out of Cape Cod to the scene even when the helicopter was already in the air (it was diverted to the scene). That was a scene close to South Portland, about as far as Jewell Island, and it strongly suggests that the fastest and easiest way to respond in some way to the distress call is sending either of the boats.

The question is, what will a 25' RB-S of the Defender B-class have in the line of communications gear, sensors, CIC or other homeland security / law enforcement stuff that allows them to find, localise and analyze the jamming, as well as checking if there is any sign of a riot, hostage situation or some kind of threat at the asylum?

Can they tell from a distance whether any story the Warden chooses to try to avoid them coming ashore is false?

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Find out where it is, give them a heads-up, and get crews together for those boats, too.
I expect notifying the crews of USCGC Jefferson Island and Marcus Hanna will be done regardless of anything else. Informing people already out is lot less likely to face scrutiny later or to be called wild alarmism by an annoyed senior officer.

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It's a pretty good long-range radio system, and may be powerful enough to cut the effective range of that jammer, if they turn off the Automatic Link Establishment, which the jammer will be upsetting.
Would they be condtantly trying to reach Agent Banks and O'Toole on the DHS radio network frequency as well as the Coast Guard emergency frequency that O'Toole used?

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Not from that - that's a web page from their PR department.
Well, it mentions systems that appear to include radio and shipboard C3I, so I was hoping some of the system names told you more than me.
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Old 02-17-2017, 09:14 AM   #40
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Default Re: Detection and analysis of jamming by the Coast Guard

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I found that there are two 47' MLBs in South Portland and one of them is always kept ready for instant response, usually for a life-saving operation. There is also a 25' Defender B-class RB-S at the ready, with a watch-standing crew.
Send the Defender: it's a lot faster and has guns.
Quote:
The question is, what will a 25' RB-S of the Defender B-class have in the line of communications gear, sensors, CIC or other homeland security / law enforcement stuff that allows them to find, localise and analyze the jamming, as well as checking if there is any sign of a riot, hostage situation or some kind of threat at the asylum?

Can they tell from a distance whether any story the Warden chooses to try to avoid them coming ashore is false?
Give me a little while to read the boat's operator's manual (warning: huge download).

Quote:
Would they be constantly trying to reach Agent Banks and O'Toole on the DHS radio network frequency as well as the Coast Guard emergency frequency that O'Toole used?
Regularly, but likely not constantly -- there aren't going to be that many people on-shift, and they still have to listen for other distress calls.
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