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A comment on Ask HN: Iran's 120h internet shutdown,Phones back. How to stay resilient?.

Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by bb88 on Tuesday January 13, 2026 @05:07PM (#46608973)
States like Iran have signal catchers, where they can get a rough idea where a signal is coming from through triangulation. The US military has had this for over 20 years now. Often these coordinates are fed in as targets into weapons systems.

If you're going the radio route these come to mind:

Meshtastic: 1W, one band, local. Useful if Iran doesn't know about it. But easy to jam and probably triangulate.

Wifi Halow: 1W, can possibly hop between bands, but probably also really easy to jam and triangulate.

WSPR: Possibly good, transmitters can hide in the noise floor, and can go long distances with 100mW of power, but slow. Probably triangulable, very easy to jam once located in the spectrum. Data can be transmitted and received with off the shelf components.

Military Radios: Very good. Transmitters can frequency hop, making triangulation and jamming difficult. Also encryption. You can easily transmit in the same frequency space that Iran would be using to avoid jamming. But also, mostly unobtanium. I have heard stories about US military radios showing up at Ham Fests.

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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by SOLAR_FIELDS on Tuesday January 13, 2026 @11:57PM (#46612509)
Not knowing much about radio hardware your post made me wonder why we don’t see too many options for radios that can do this outside the military. Is it because there’s rarely a practical use case outside of avoiding jamming? Or is the hardware to do so prohibitively expensive?
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by deepsun on Wednesday January 14, 2026 @12:06AM (#46612541)
Radio spectrum is licensed, and licenses are very expensive.

There are several bands for Amateur radio in US/EU/AU, but it is explicitly forbidden to use any kind of encryption on them. So no one can sell devices that use encryption on those bands.

And I doubt Iran was friendly to amateur radio in the first place. E.g. in USSR it was crazy to think of any non-approved radio.

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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by whatever1 on Wednesday January 14, 2026 @12:52AM (#46612799)
I mean who can stop you from transmitting anything you want at any frequency? Licenses etc only matter when the rule of law is a thing.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by nerdsniper on Wednesday January 14, 2026 @02:19AM (#46613293)
It's trivially easy to watch the entire radio frequency range at once and triangulate the location of any transmission. If someone more powerful than you wants to stop you, they can.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by markus_zhang on Wednesday January 14, 2026 @06:33AM (#46614869)
Just curious what if the transmitter hops freq around? What is the tech to track these?
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by heljara on Wednesday January 14, 2026 @08:17AM (#46615704)
It's (scarily) available in the commercial sector[1][2] from space if you have the need to purchase their services.

Suffice to say, military and intelligence agencies are probably a few generations ahead of this and you won't find them commenting on strategic capabilities on HN.

1. https://www.he360.com/ 2. https://spire.com/space-reconnaissance

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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by markus_zhang on Wednesday January 14, 2026 @11:05AM (#46617716)
Thanks! Technically, what do you think is the biggest obstacle to achieve military grade hopping? Is it just cost, or something you simply cannot buy from open market AND cannot make one if you have the knowledge?
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by nerdsniper on Wednesday January 14, 2026 @02:44PM (#46621760)
Military frequency hopping / spread spectrum isn’t really about preventing being noticed, it’s more about making it harder to jam. If you don’t have physical safety from the people “more powerful” than you who want to stop you, then they will still locate you easily and stop you using physical force.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by a012 on Wednesday January 14, 2026 @01:10AM (#46612893)
Once you transmitted, you’re exposed so the authority can find you sooner or later
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by wolvoleo on Wednesday January 14, 2026 @02:32AM (#46613351)
Well yes but you could of course choose not to stay at the location you transmit from.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by deepsun on Wednesday January 14, 2026 @03:16PM (#46622418)
Parent was asking about jamming protection (frequency-hopping, encryption) devices.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by tdeck on Wednesday January 14, 2026 @07:02AM (#46615096)
There is actually a lot of fairly inexpensive SDR hardware aimed at amateurs, and other ways to do cheap packet radio. But outside the amateur radio community you might not hear about it because you need a license to transmit.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by wolvoleo on Wednesday January 14, 2026 @02:31AM (#46613348)
WSPR carries almost no payload data and by default it literally broadcasts your location. You could modify it but it will still take ages to send a short sentence which is probably the last thing you want when you want to avoid getting caught.

Short bursty spread spectrum hopping seems to be more what the military do and they also care deeply about triangulation.

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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by tdeck on Wednesday January 14, 2026 @06:59AM (#46615072)
Just to underscore this WSPR sends 50 BITs of data in 110.6 seconds - a data rate of less than 2 baud. It's not practical for really any kind of message passing. Using CW (Morse code) would be at least an order of magnitude faster.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by bb88 on Thursday January 15, 2026 @09:28PM (#46642313)
But then you're no longer in the noise floor. That makes you triangulable and bomb-able.
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Re:Ask HN: Iran's 120h internet shutdown,Phones back. How to... by bb88 on Thursday January 15, 2026 @09:04PM (#46642162)
My point is that if you can't do spread spectrum, you've got to think about creative ways to get messages out. Something in the noise floor looks promising even if it's not fast. Further I've seen designs for WSPR that allow the radio to be something like a TTL buffer chip.

If you "announce" yourself you become a target for the signal intelligence folks. Sat phones became a liability in the 2nd gulf war, as they lit up like a beacon saying: "Bomb goes here!".

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