GPS - Comms question

[Jo Zebedee]

back to my UFO hunters....

The army have cut wifi and mobile communications to the village centre where they have brought the holiday makers while they deal with the little incident in the woods. But I need word to get out (so the villagers can all panic and realise the truth, mainly) and I have a TV presenter in the village who has connections to break the story and who is also an experienced UFO hunter. What sort of communications equipment could he have with him to bypass the comms block? GPS?

 

[Venusian Broon]

Aaaah I get now where you were going with the first sentence you wrote ages ago...(I'm a man, takes me ages to make connections. )

Hard-line communications - phones and what relies on the phone - i.e. internet via DSL/cable modem etc... is by far the easiest thing to cut. Essentially all the wires from the village go to an exchange and the line can be cut just after that.

Mobile comms would be harder to enforces - they could take down the local base stations, but if you were out and about you could connect to a base station further away. So the reporter could go on a trek to find a signal. (possible plot development?)

Other than that - a satellite phone/internet connection would be almost impossible from them to stop (unless they stormed the headquarters of the company supplying the service and shut down the service from there.) Very useful in certain parts of the world where mobile and hard-line communications are sparse or non-existent. So if he has done work overseas then I'd definitely buy that he would have satellite communication equipment. Also it is being marketed to areas of Britain where BT and even mobile don't go, see:

https://www.satelliteinternet.co.uk/

Or just type satellite phone and broadband into google!

 

[Ray McCarthy]

GPS is purely one way near line of sight (About 1400MHz) from Satellites. It's practically just time codes and ID of a satellite. By receiving 3 to 5 at the same time (all GPS have multiple receivers, more expensive ones have more) the GPS software by the time differences and data about satellite positions calculates where you are. It does nothing else. The signal is useful as a clock source or to syncronise transmitters far apart, which is why all Mobile Masts, DTT masts and and DAB masts rely on GPS. If there is a Solar storm or wide spread GPS jamming you can lose most Mobile Phone, Mobile Internet, SMS, DAB Radio and DTT.

WiFi is only very short range. Why would they rely on it?

PMR446 is only maybe a 1/4 mile in built up area, but these £25 a pair (and all makes interwork) all are same power and 8 channels (the alleged more channels are just Selective calling, with that off you hear all Selcall channels!). But on a hilltop or exposed high room with window facing a similar one with nothing in between a range of 30 miles is possible.
CB with 6ft to 8ft whips (and I have a set of four 40 channel Legal UK hand helds) have 2 miles (built up) to 200 mile range or sometimes 1000s of miles. The decent handheld ones eat batteries (often 10 x NiMH/NiCd rechargable or 9 x Alkaline and a dummy) in about 15 to 20 minutes of transmit time (all day listening only).

Or you can have a licensed Radio Amateur. They have battery gear that can do 1.8MHz to 440MHz (different licensed bands). The military could jam, but they need a court order impossible to get outside of War time or they wouldn't do it. The UK could be sued by international agencies.

There is a way to make ANY AM/FM radio into a Morse code transmitter for FM and MW bands.

 

[Ray McCarthy]

I think I also mentioned Thuraya as a cheaper option than Inmarsat and Iridium satellite phones, though unlike them not World Wide. It does cover North Africa, Europe west of Ireland into Atlantic, all of UK as far north as Denmark/Scotland an Mediterranean / North Africa / Middle East / Gulf. Not sure what Eastern Europe coverage is.

A fence wire as aerial for MW, and torn up earphone of MP3 as jumper wire and soldering iron by heating nail /splice tool on penknife with lighter I can make a pocket MW radio into a transmitter for morse in about 5 or 10 minutes. (I don't actually really know morse myself). About 2 miles range, or more with someone specialist listening. The "morse" keying is by connect/disconnect battery (connected is a dot or dash depending on duration).

A set with VHF-FM can be modified to transmit on its aerial (some do ANYWAY!) but only about 100m Range, but many miles from high up window or hill top. Again easily morse. But you CAN use an ear piece as a microphone and if it's a digitally tuned model (LCD display and up/down arrows), then another 5 minutes adds voice transmission. You can easily (illegal and stupid) make it transmit on the Air Band between 110MHz and 130MHz instead of VHF band.

 

[Venusian Broon]

(I don't actually really know morse myself).

Exactly! Who would you be sending a morse message out for

I like your radio solutions - but they do seem a bit desperate . Especially as this seems to be set out in the middle of the countryside. Now if the story was set in the urban jungle and our protagonists were caught in a huge tower block, then perhaps there could be a pirate radio DJ with reasonably professional equipment that could broadcast to the neighbourhood (and presumably to people actually listening!)

 

[Ray McCarthy]

Actual non-phone Satellite Internet needs a large fixed very accurately aligned dish. I've tested three systems. Someone REALLY good might align it in 10 minutes. Takes me about 20 with specialist meter. You don't need a pole. I've set up dishes just propped against a box on a path as a demo. Often systems have a "patio" mount which is a short pole and the base has holders for four stacks of concrete blocks.
The ordinary domestic dishes will NOT work on back of a pickup. The platform moves too much. The ones used by broadcasters have two motors and GPS. They automatically point at satellite within a couple of minutes (no manual alignment) and the motors compensate in real time for the suspension. Even more expensive ones are used on ships and planes that cope with the vehicle actually moving!
Pointing accuracy for ordinary size two way Internet dish is about 0.2 degrees for good signal and better than 0.6 degrees for a link in clear sky.

A Zone 1 Sky dish is only 45 cm. A typical Internet two way dish is 90cm and if everything else was equal needs x4 accuracy in pointing. Most two way Satellite (not Phones) is now Ka Band not the Ku used by Sky/Freesat and thus needs x8 accuracy to x16 accuracy in pointing compared to a 45cm Zone 1 Sky dish!

 

[Venusian Broon]

Actual non-phone Satellite Internet needs a large fixed very accurately aligned dish. I've tested three systems. Someone REALLY good might align it in 10 minutes.

I can imagine to jerry-rig it, might be a bit tough. Perhaps as another idea for Springs to think about, if the UFO crash site is in a reasonably remote part of the UK then there could be a house that did have satellite internet installed already. Would it be believable that the Government might miss that there is such a service in the area, (until the journalist gets the message out so they send troops in to 'shut it down')???

 

[Ray McCarthy]

morse message

If sent slow enough I can do it with my convenient table/chart I carry in the car. Also then anyone can decode in the same way. If pre-arranged as a back up it's feasible.
Also I DO hook my laptop to Radio to send and receive morse. If you have a serial port and cable, the morse on the poor transistor radio can be typed as text on laptop.
PC software also decodes Morse (Marine Operators are managed well, other computer perfectly, poor morse badly). Very much morse today, especially in competitions is actually machine generated. One radio I have has limited built in Morse generation.

 

[Ray McCarthy]

There are even web sites the person at base can type morse into ...

 

[Venusian Broon]

If sent slow enough I can do it with my convenient table/chart I carry in the car. Also then anyone can decode in the same way. If pre-arranged as a back up it's feasible.
Also I DO hook my laptop to Radio to send and receive morse. If you have a serial port and cable, the morse on the poor transistor radio can be typed as text on laptop.
PC software also decodes Morse (Marine Operators are managed well, other computer perfectly, poor morse badly). Very much morse today, especially in competitions is actually machine generated. One radio I have has limited built in Morse generation.

Perhaps more importantly would Spring's potential YA readers have a clue what on earth Morse code was?

I'm an old 43 and I would not think at all about using or receiving Morse, never mind trying to decode it!

 

[Jo Zebedee]

I won't be going into any more detail on the hows than he did x to get the news out in dialogue. That being the case - he used a satellite phone - believable?

 

[Venusian Broon]

I won't be going into any more detail on the hows than he did x to get the news out in dialogue. That being the case - he used a satellite phone - believable?

Simple and believable. YES!

 

[Ray McCarthy]

Would it be believable that the Government might miss that there is such a service in the area, (until the journalist gets the message out so they send troops in to 'shut it down')???

They can't know without a warrant to ask the ISP where you are. The ISP can't actually KNOW where you are.
Which ISP?
It's impossible.
The Groundstation for a UK user is in Spain or Italy (depending which service you use).
NO-ONE knows were you are. Satellite Internet unlike satellite phones only knows if you are in the Satellite footprint and connected!
For Ku band that's all of Western Europe!
For Ka band it's all of Ireland, either 1/2 of Scotland and 1/3 of England/Wales/Cornwall!

 

[Ray McCarthy]

Satellite phones DO have location data, Inmarsat, Thuraya or Iridium are the only three options. They will co-operate to block an area or phone.
I used to work with these sort of companies. So only real two way radio or a domestic two way internet hauled in back of car and set up in 15 to 20min on the ground will work if they are closing Mobile bases.

 

[Jo Zebedee]

I think I'll go with satellite phone - if it wouldn't raise eyebrows for VB then it should stand up fine for the audience I'm writing for. Plus, I can be pretty woolly - "my dad has so many gadgets, he'll have done whatever's needed to get the call out..." sort of thing.
So long as it's possible and nothing that required A-team like levels of innovation with loo roll holders it'll work.

Thanks, both! You're amazing!

 

[mosaix]

Hard-line communications - phones and what relies on the phone - i.e. internet via DSL/cable modem etc... is by far the easiest thing to cut. Essentially all the wires from the village go to an exchange and the line can be cut just after that.

Not necessarily. In some small villages the exchange can be suitcase size and located in loft of someone's garage or the village hall. Phones are connected to it by wire but the connection from the mini-exchange to the national network can be wireless.

 

[Ray McCarthy]

All UK Terrestrial phone and mobile can be disabled remotely. They don't need at all to physically access anything. Some full size exchanges are "wireless". A microwave link can be 20Mbits to 1Gbps easily.
Usually Mobile bases and phones are remotely disabled in the Network control centre of the company. I've been in one.

 

[Ray McCarthy]

satellite phone

1) Thuraya = Private Arab company. Take them ages to get them to do anything. Far the cheapest and some models look nearly like regular phone and have adaptor for netbook/laptop. Also works on Terrestrial Mobile. Cheaper because not Worldwide. They might even ignore a UK request for a while, or indefinitely.

Worldwide:
2) Iridium went bust so US Military bought it. Pretty instantly you can be turned off, certainly listen to UK. No idea of price.

3) Inmarsat: The phones are more like suitcases. But you can get more speed (if you pay). Run by International Maritime Organization, so they will listen to US, UK governments, but not say Iranian, North Korean or Syrian to turn off a user.

There isn't anything else. Thuraya, Iridium or Inmarsat would be quite happy to be mentioned (as long as not negative!). Since there only are these three and quite different physically, pick one and mention by name. If it was my story I'd avoid Iridium! Thuraya for most of Europe, UK & Ireland, Med, Middle East, Gulf and North Africa, Inmarsat as bulky Backpack worldwide option.

 

[Venusian Broon]

Seeing as Springs is writing fiction, can't she just make up a satellite phone company if it's absolutely necessary to mention a brand? (and one that the British government can't switch off)

I have no idea if Springs wants to be absolutely tied to reality, but perhaps it is just a plot device to move things along (and anyway the main point about the story this is that an alien space ship has crash landed in Britain, surely it would be all right to have other things that are fantastical )

 

[Jo Zebedee]

Seeing as Springs is writing fiction, can't she just make up a satellite phone company if it's absolutely necessary to mention a brand? (and one that the British government can't switch off)

I have no idea if Springs wants to be absolutely tied to reality, but perhaps it is just a plot device to move things along (and anyway the main point about the story this is that an alien space ship has crash landed in Britain, surely it would be all right to have other things that are fantastical )

I don't need any detail, really - my pov character knows nothing about any of this. She just needs to know a call went out past the block. Doesn't matter how, who or what provided it's possible.