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Topics - Brian

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General Discussion / Cheap Dual-Band HT
« on: December 31, 2012, 07:10:49 PM »
If you're interested in a cheap handheld dual band (VHF/UHF) 5 watt radio, with narrow band capability, check this out:

The cost is $65 US for an individual one, and $300 US for a six-pack.  The radio gurus I know think it's a heck of a bargain, and I sprung for one for Kate's Christmas.  It looks okay to me, though the instruction manual could be a bit better, and I'll probably be getting a second one.  And several of our SAR folks (as of now, the people of our rope team) are considering it, too.  I think we'll get at least one six-pack. (1)

My radio gurus recommend springing for the programming cable (programming software is free), but to skip the high-gain antenna (which apparently  doesn't offer much advantage).

The down side:  Unlike our Yaesu FT-60R radios, it probably isn't very weatherproof, nor will it accept AA or AAA batteries.

But it's very small and I've never seen anything like it for the price.

(1)  Our agencies are changing from wide-band to narrow-band, which is a capability our current radios lack.  This has engendered quite a bit of grumbling amongst the troops, since many of us have gotten our ham licenses and purchased several wide-band radios each, at considerable personal cost, specifically for our SAR activities (base station, with antenna, coax cable and power supply; mobile radio for vehicle with antenna; and HT, plus accessories like extra batteries, speaker mic, high-gain antennas, etc.).

Just FWIW.

Satnav (GPS GLONASS COMPASS Galileo) / Iranian spoofing
« on: December 18, 2012, 04:58:05 PM »
Interesting post on the entitled: Iran Hacks Ships At Sea

The never-ending game continues.

Key Grafs:

". . . Iranian agents are offering deep discounts to buyers willing to create false documents and move the Iranian crude. This is risky, for those who get caught can be prosecuted, jailed, and fined. But Iranian smugglers know who is willing to take chances, if the payoff is large enough. Selling oil at discounts of 30 percent or more still costs Iran. So also does the expense of secretly buying tankers that will pretend to belong to another country while moving the black market oil. This is where the false GPS locations are put out by the transponders.
"The U.S. and the UN are alert to these schemes and the great game of cat and mouse is on. . . .
". . .This can work for a while, but a nation with lots of recon satellites, warships and cooperation from most of the world’s shipping, can get around this.
". . .The Iranians are aware of the satellites and other means of double-checking transponder data and is constantly coming up with schemes to confound the American snoopers. Since Iran has been under sanctions for decades for being an outlaw state, threatening more punishment is seen as a challenge not a threat."

Regional SAR teams / Farewell, Sara
« on: August 15, 2012, 06:05:32 AM »
A couple of months ago, the residents of our county voted down a levy that would have funded our sheriff's office at what was even then an inadequate level. 

Most of our county employees, including most of our prosecutors, sheriff's deputies and the sheriff office's staff have been terminated.

Our Emeregency Services Coordinator, Sara Rubrecht, was guaranteed a final year but nothing thereafter.  For personal reasons she needed more job security than that . . . and so took a job in a neighboring county.

Sara was unbelievably good, and having worked closely with her for 4 years or so, I came to appreciate her as the very best in the state, and, I'd wager, in the entire west.  Frankly, mere words are inadequate to describe her and what she's been able to accomplish.

Suffice it to say that in her 12 years as our county's Emergency Services Coordinator, she took our embarrassingly ramshackle gaggle of individuals and built it into a highly competent unit of unpaid professionals.  She created an organization that became a model of what SAR should be, and it was largely through her efforts that a consortium of 9 adjacent counties became an effective cooperative unit.

In 2010, Sara was presented by the Oregon State Sheriff's Association with their "Search and Rescue Coordinator of the Year Award," which she richly deserved.

I hope we can exist without her, but I'm not sure that we can.  She was special.

Here's a tribute to her.  It captures much of what Sara is.

Farewell, Sara.  If you ever need us, we're here.

New Satellites Could Make GPS SATNAV ( :D) Harder to Jam or spoof

The operational word seems to be "harder".  The increased capabilities appear to be an incremental step towards protection . . . albeit a useful one. 

(I'm not sure protection will ever be absolute.  There is this pesky game of leap-frog . . . protection/defeat protection;  protection from the defeated protection/defeat the protection from the defeated protection, etc.)

Regional SAR teams / A Tough Search
« on: May 25, 2012, 05:20:02 AM »
Here's a report on a search by JoCo County's own Ann McGloon.  These folks are our very best, and trust me, this is a must read.

New Techniques & Learning / OSSA Academy - merged topic
« on: April 20, 2012, 06:32:56 PM »
So we've just finished this year's OSSA (Oregon State Sheriff's Association) Academy, a course of instruction with written and skills tests that everyone wishing to join SAR must take and pass.  It consists of 2 weekends, 3 weeks apart, plus an outdoor survival/camping/search exercise, to come in May.

Our student body consists of a wide range of people, some with college, some without, some quite old, some youngish, some with vast outdoor experience and some whose outdoor experience is quite limited.

We've organized our formal teaching into two parts:  the first weekend is devoted to teaching what the students need to know to pass a basic written test.  The second weekend (3 weeks after the first) focusses on more practical skills with lots of hands on and some field exercises.  The search/survival/camping weekend follows as a culmination.

For now, I'll summarize only what I taught the first night, and it's just FWIW.

Friday Night:  18:00 - 22:00

   1.  Intro to GPS.  The only question on the written test was about things that could compromise a Sat Navs ability to locate itself.  This is a subject near and dear to my heart, since too many people believe their GPS units are infallible. 

(We've had to search for several lost souls who put their trust in their Nuvi GPS systems.  The most memorable of these involves a lady with 3 children who followed her GPS's instructions and ended up exiting from a paved road in one drainage and, following an increasingly narrow skid road, wound up in another drainage, where she faced a steep rise on one side and a sheer drop-off on the other.  It's a powerful example.)

Now, I could have covered what compromises GPS accuracy in 10 - 15 minutes, but I had a full hour and, never one to miss an opportunity, I took 45 minutes to cover some principles of operation, the better to achieve understanding(1).  So this is what I taught, in sequence.

   a.  The 3 segments of the Sat Nav system (ground control, satellite constellation and receiver) and how they work together, emphasizing what a satellite "says":  my name is X, my location is Y, and the time is precisely Z.

   b.  What a GPS receiver is (radio receiver, clock and calculator), and how the concept of GPS location depends on the simple formula:  Rate X Time = (pseudo) Distance.

   c.  What I want in a GPS receiver (great antenna, durability, AA batteries, weatherproof).

   d.  What accuracy is and is not:  "I'm 95% sure I'm located within 3 meters of . . ." and what that means in real world applications (really, twice that distance), plus there's always that pesky 5% chance it's outside that 3 meter distance.  (I also covered why seemingly identical units show slightly different coordinates for exactly the same location.)

   e.  That one can pinpoint one's location in a 2 dimensional world using 3 circles, and then showing why that doesn't work with a 3 dimensional GPS system, which needs at least 4 spheres (=satellites) in order for a receiver to accurately locate itself. This amounted to explaining a 2D vs 3D position fix, the former unreliable, the latter reliable.  Example of a Colorado elk hunter's experience made the real world point.

   f.  Sources of error and potential error:  bad batteries, satellite geometry, too few satellites (more a problem with older receivers), multipath, spoofing, jamming, weak signal (under wet canopy), electrical interference, sunspots incorrect datum, etc..  With personal & SAR examples.

   g.  WRT vehicular units (Nuvi), making a distinction between the unit's ability to locate itself (pretty darned good) and it's ability to construct a route from one location to another (100% accurate 80% of the time . . . or so I taught . . .) with personal & SAR examples.

   Just for what it's worth.

(1)  I used the additional 15 minutes to increase the length of my survival lecture.

Navigational Questions & Answers / Heading, Course and Bearing
« on: March 14, 2012, 01:02:28 AM »
I teach the following:

1)  Heading — the direction I'm facing.
2)  Course — the direction I'm traveling.
3)  Bearing — the direction of my destination

My logic, and I don't know where it came from, is that if one is being swept in one direction by an air or water current, one would need to face and propel oneself "upstream" (heading) in order to maintain a line (course = the resolution of vectors of travel and current) to one's destination (bearing).  Ideally, "course" and "bearing" would be identical throughout my travel.

(I believe I've seen some Satnav receivers that don't even mention "course", but use the term "heading" instead.)

Thoughts?  Criticisms?  Elaborations?

Compasses / Parallax or Quality Control or . . .?
« on: March 04, 2012, 05:09:46 PM »
A person on Amazon reviewed one of the Suunto compasses (MC-2DLIN), said this  :

". . . Overall the compass is a well made example of a classic design and first impressions are very good. However, on close examination of the compass needle capsule it is clear that the alignment arrow in the base of the compass capsule and the parallel alignment marks/declination scale indicator are slightly offset. This indicates that the two scales are not concentric. . . ."

This concerned me because I have a Suunto M3 Global (it's all Lyle's fault . . . ;)), and  I assumed that the capsule, baseplate and declination adjustment are the same — or almost so — in the two compasses.

So I tested my M3 using a map-reading grid (in lieu of the graph paper the reviewer had used) and wrote a reply to the effect that at first, it did seem to me that there was a QC issue, but when I moved my head around a bit, it seemed I could make the problem disappear from where it had been but reappear elsewhere, and I wondered if it might not be a case of parallax.  (Lyle stresses the need to eliminate parallax when discussing proper compass use.)

Anyone have any thoughts on this?   If I'm wrong, I'd really like to know it so I could correct what I've written there.

Thanks all.

General Discussion / Digital recorder
« on: March 04, 2012, 04:55:56 PM »
Does anyone know of any digital recorders that one could carry in the field? 

I ask because our dog flankers, who really have to hump it to keep up, double (or quadruple?) as comms, navigators and scribes.  It occurs to me that having a waterproof, shockproof digital recorder would be a real boon for us (well, the flankers . . .).  I wouldn't want it to be vox. 

Thoughts?  Experience?  Good idea?  Bad idea?

Satnav (GPS GLONASS COMPASS Galileo) / Jamming and Spoofing
« on: February 24, 2012, 05:12:51 PM »
I guess it was just a matter of time before the world took notice of the ease of GNSS/GPS jamming and spoofing, but it seems that time may now have come.

Here are 3 pieces reporting on the same jamming project (Sentinel), each with its own twist.

Sentinel project research reveals UK GPS jammer use

UK Sentinel study reveals GPS jammer use

Could defence sector help avert GPS disaster?

That clatter you heard was my jaw hitting the ground when one of these sources reported that the super-secret US drone that went down recently in Iran might have been equipped with a civilian grade SatNav system (no encryption, no authentication).

Is such a gross mistake possible??? (That's a rhetorical question . . . don't answer.)

Maps / Maps of Ireland
« on: February 14, 2012, 02:15:08 AM »

Can someone please give me some advice on maps of Ireland? 

Here's the situation.  I have a friend who has a Garmin 62s.  He wants to walk.  He needs (a) map(s), preferably large-scale.  The map(s) must have a format (grid/coordinate system).

As a 'mericun, I haven't a clue what's available on the other side of the pond.

Is there a reasonably-priced e-map of Ireland?  (Here in the US, we can get Garmin's electronic topo maps, 1:24,000, for 2 (or 4) states, for less than $100.  Is there something equivalent available for Ireland?)

What are the paper options?


General Discussion / Computer Mapping Programs
« on: January 19, 2012, 02:17:10 AM »
Our (Josephine County, Oregon, USA) SAR unit (indeed, I'd guess all such units in the state of Oregon) uses computer mapping programs to print paper maps for searchers and to import tracks and "Points-of-Interest" from, and export the boundaries of a search area to, SatNav receivers.

I haven't surveyed Oregon's search managers, but I'd bet my bippy (if I had one) that Oregon search managers mostly depend on National Geographic's TOPO! and/or Terrain Navigator Pro (Maptech).  (Our JoCo people use both.)

Some of our state's managers may use Garmin's "Basecamp" with or without either of the other two.  (Mea Culpa . . . it took me 2 years to delve into Basecamp, and I find it to be a valuable resource.  Dumb me.)

And, since I'm a Mac kinda guy, I also like MacGPS Pro (the more I use it, the better it becomes).

Are there others out there who use computer mapping programs?  If so, what do you use, and how do you use them?  What are the positives and negatives of them?

Satnav (GPS GLONASS COMPASS Galileo) / SatNav Unit's Electronic Compass
« on: January 07, 2012, 02:04:06 AM »
I haven't seen mention of this, ever.

Question:  Does the electronic compass of a SatNav receiver respond to the proximity of ferrous metal?

Answer:  Yes

We all know that a conventional magnetic compass is influenced by electromagnetic and ferrous metal, but how many of us thought to question whether or not they influenced electronic compasses, as found on (for example) Garmin SatNav receivers?

I haven't bothered to test electromagnetism, but I'd bet my bippy (if I had one) that the electronic compass in SatNav units can be influenced by them, too, just as ferrous metal can influence them.

Just for what it's worth . . .

Wired has an article with that title.

The article reports on the LightSquared debate, sunspots, the use of SatNav for understanding our world in general better, the threat of (illegal) SatNav jammers, and mentions the new non-GPS Boeing Timing and Location system.

If nothing else, we're reminded yet again of how delicate a system SatNav is, and by implication the importance of maps and compasses . . . and knowing how to use them.

Regional SAR teams / A Day on a Search Mission
« on: November 06, 2011, 06:20:34 PM »
I thought the readership might be interested in seeing a photo-montage entitled "A Day on a Search Mission" that my wife Kate put together for her SAR blog  (She and a couple of other Josephine County searchers took those pictures and others - see below - during a search conducted on Wednesday, 4 Oct.)

In short, on Saturday, 29 October, and after a week of elk hunting in the mountains of neighboring Douglas County, Oregon, two hunters separated in the early afternoon to hunt different areas.  Neither was going far from camp, both knew the country very well and each knew the location to which the other was headed.

One hunter failed to return to camp, and that evening the other set out looking for him.  The next day, his evening search having failed, the hunter reported his friend missing and the county's hasty teams were deployed. 

The missing hunter was 70 years old, had some health issues (including a bad knee), was dressed in camos and carried a rifle and a camo pack.  He was an experienced outdoorsman and had fire-making equipment.  No gunshots were reported.

Our county (Josephine) and I'd guess 2 - 3 other counties sent (mainly) dog teams on Monday (there were 6 dog teams working), and the overall search continued through Wednesday, when an incoming weather front forced operations to be drastically curtailed.

Alas, the subject still has not been found, and aside from a few (cadaver) dog alerts on Wednesday, we don't have a clue where he might be (the terrain is dense and impenetrable in large areas, so it would be really easy to miss him . . . unless a searcher stepped on him).

The weather Monday was downright nasty with heavy rain and temperatures in mid 40s F for a few hours in the morning, followed by a drop in temperature with fog and strong wind in the afternoon.  Our people were miserably cold, and if that weren't bad enough, large swaths of search areas were covered with vine maples which had yet to drop their leaves (mercifully, the leaves were down by Wednesday's search).

We who searched Wednesday went equipped for the worst, but the weather had turned good by then (clear and in the 50s through late afternoon).

This is gnarly and tough terrain in really big country.  The elevation isn't extraordinary, but the steeps are . . . well . . . very steep and sometimes long, and the slopes were very slippery.  In fact, there were many places where I'd have been on rope were we not side-hilling.  Fortunately, there were some vegetable belays which were sometimes helpful for safety, but were very dense and hard to move through or see through.

It can be difficult to navigate such areas without a GNSS (I LOVE my Garmin 60Cx's antenna), since all the ridges and valleys can look alike . . . that is, if you're fortunate enough to see ridges or valleys through the timber and/or fog.

Below, I've listed Kate's posts about how the search developed, where you can see more photos (click on the photos to enlarge them).  One of the posts includes a local TV channel's report of the search.  For sheer scale, I recommend clicking on the top left photo from the Nov-4B entry.  There are 3 searchers in the meadow.

Nov 1 blog entry —
Nov 3-A blog entry —
Nov 3-B blog entry —
Nov 3-C blog entry —
Nov 4-A blog entry —
Nov 4-B blog entry —

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