Posted on 04/26/2013 3:55:59 PM PDT by Perdogg
Fox News’ Catherine Herridge is reporting today that the FBI has not ruled out the possibility of a third party involved in the Boston Marathon terrorist bombing. Evidence that the two bombs were detonated not by a cell phone but by parts ripped from a toy car remote control suggest that whoever triggered the explosions had to have been in the line of sight of the bombs.
(Excerpt) Read more at twitchy.com ...
.... Just a note about the detonations ... They occurred about 300Ft (90 meters) and apart 10-12 seconds apart ..... still quite a distance.
I would guess, if they really did use toy car radios, that they either picked two with different frequencies, or tweaked the frequencies, or used the PCM (Pulse Coded Modulation) of the signal to detonate the two at different times. Think right/left, go/stop functions on a toy car. That's 3 active functions at a minimum.
Or just used on signal with a delay, intentional or not, on one of the bombs.
What I'm saying is that technically, I could cause a remote event using toy car radios a block away, and time them however I wanted.
I certainly wouldn't want to do that to innocent civilians, but if you want to set up a test, get a spot of desert, and some jihadis, and I'll make their shock collars go off from a couple of hundred meters away.
/johnny
WOW!
Were there actually any Saudis running in the race?
How come there were so many Saudi “spectators” there?
“....a toy car remote control suggest that whoever triggered the explosions had to have been in the line of sight of the bombs.”
.
How many muslims lived in the line of sight of the explosion?
Did they ever find out who the dude on the roof was?
I’m thinking puffy coat man is wearing a disguise.. And pushing a stroller? Yikes.
i thought most injuries were legs and feet. why his hands and both of them at that.
they tackled him running from the scene i heard.
maybe john king and cnn were right all along.
That was a guy who had an apartment in the building and he was watching from his rooftop garden (or so they say.)
Good deal - you cannot beat real life testing. Could be that a simple wire is all it takes.
But ... (you knew there would be a but)
What is the diameter of 26 gauge? The reason I ask is that you would get better and more predictable performance using a coaxial connection from antenna to the triggering device. I’m betting .050 inch coax would be OK. But it would be harder to seal.
But I’m just guessing on the coax. Don’t kill yourself testing out my crazy ideas.
You don't need coax. I do a LOT of my shortwave on ladder line, and that's for comms thousands of miles away.
No coax involved.
/johnny
The difference here that you are routing your signal with a bare wire into a Faraday Cage when you use a pressure cooker. That could make a difference - that is my reason for saying coax might be required. I once designed a 2 Ghz receiver on a circuit card that used a simple wire for its antenna. So I know that works just fine.
So I agree on the half wavelength antenna. What is the frequency here. How long is that wire? Pretty long if 45 MHz. Pretty short a 2 Ghz but that would be line of sight.
I'll take my 50mw 50.080MHz Altoid box radio tomorrow and use it as a test signal, and put one of my handi-talkies in the pressure cooker with the magnet wire antenna and try it from 100 meters and see what the results are.
I'll consider it good if I can break squelch on the handi-talki.
I'm betting it will work. I've done a lot of QRP mobile and field.
/johnny
A) it's not a bare wire, it has a thin coat of varnish on it for insulation.
B) most RF and IF sections of commercial radios are under metal covers (faraday cages) for isolation, and a simple wire connects them in the gozintas and comoutzas.
Impedence matching isn't going to be that much of a deal breaker like it would be when the signal is 80db down in the noise. We're not building a stellar radio mapping machine.
/johnny
You are a gem! What would we do without FR?
Are you going to have 6 ft. antennas at both ends of the link? And I’m assuming you can coil up those antennas a bit to reduce their size. Think about how the mad bombers would have managed this inside a backpack and on their person.
Your talking very complicated design. Could the two brothers have figured that complex design on their own? I bet not.
Other than sending my callsign as required by law, I'll break squelch and walk away until I don't break squelch again. I've got most of the area around here sorted out for distance markers (just something to do when bored) and I'll see how far away it works.
/johnny
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