101–110 of 196 posts
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but then it's not a click bait
I'm not in the market and clicked the link out of curiosity, but yes, I can turn my android phone into a hair dryer if it takes $35 of auxilary equipement.
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Sim card radios exist. eg https://www.wouxun.com/radios/two_way_radio_kg-v98.aspx
Yes, but think about having a mobile that has native integration with APRS or can make voice/packet radio or even DMR. It would be perfect for hiking or adventures. Even better with LORA. Probably the main issue is RF compatibility.
But why are there no regularly recommended cheap hardware solutions that can do this (and or just hobbyist builds using an RPI). Seems like the demand would be there but perhaps I'm just not understand all thats involved.
Any insight you could provide would be appreciated.
This is a wacky idea, but the "modern" thing to do would be to repurpose seldom used 2-meter repeaters and make them 5G gNBs in the 3300 to 3450 MHz ham band (which overlaps NR band 78). Then you could directly use your cell phone (with a different SIM card) as your ham radio. Network gaming servers to the gNBs and every kid in the US will want a ham license. https://github.com/srsran/srsran_project
I went down this rabbit hole for a while a few years ago. I think it's doable, but I don't have good answers to a few questions: 1. How do you get cell phones to automatically identify in a way that satisfies the part 97 rules? 2. How compatible are modern smartphones with the null encryption cypher? 3. With fewer and fewer physical sim slots, is it possible for an amateur to produce valid eSIMs? (And is it possible…
2.- Most of them will refuse to join any Private SA network that does not use SUCI and encryption (in my experience). If you have a "nice" PLMN, they will connect. What a "nice" PLMN is varies between modems, the testing PLMN is a safe bet :)
3.- Also gone down this rabbit hole. eSIMs must be signed by a GSMA authorized key, and they are picky. Osmocom people have relationship with someone that signs profiles for them (for pay). The crypto is quite straight forward to do offline, eSIM profile distribution not so much. Key propagation from generator to core network and final client (ue) would also be a challenge. Another option is using the testing certificate, it should remain active in most modems for certain PLMNs. I have yet to test this, but work gets in the way
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I went down this rabbit hole for a while a few years ago. I think it's doable, but I don't have good answers to a few questions: 1. How do you get cell phones to automatically identify in a way that satisfies the part 97 rules? 2. How compatible are modern smartphones with the null encryption cypher? 3. With fewer and fewer physical sim slots, is it possible for an amateur to produce valid eSIMs? (And is it possible…
1.- You get a "nice PLMN" for the network and assign phone numbers (and manage key material) only after Ham Identification. DMR Style (at least here in Spain) 2.- Most of them will refuse to join any Private SA network that does not use SUCI and encryption (in my experience). If you have a "nice" PLMN, they will connect. What a "nice" PLMN is varies between modems, the testing PLMN is a safe bet :) 3.- Also gone down…
PC modems on a Linux machine are more manageable (But expensive, let's wait a few iterations on RedCap maybe). And SIMs with ADM keys can be purchased from different sources
how the turntables. Back in the 80s my grandfather (N4MDB RIP) had a ham radio in his car and used something called an "autopatch" which could dial phone numbers. He'd call my grandma and say we were going shopping or whatever. Everybody from the shack could listen in with their radios. He tried to get me interested in ham radio but at the time I was exploring the internet and ham seemed... boring? Overly fussy with…
The portable radios/cord free telephones back then were a bit of a legal gray-zone.
If it supported aviation bands, I would get it to use as a backup radio while flying. Not sure how far it would transmit though.
Plus you probably need a licence to transmit in those bands.
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I own one of these, easily the worst radio I have. Fine for receive but please don't hit that transmit button.
Why? What happens?
However, if you hack the firmware and transmit outside the bands the radio's RF is designed to transmit on, then you will probably see all sorts of spectral weirdness.
Afaik illegal in UK without first getting an amateur licence from Ofcom
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I'm not in the market and clicked the link out of curiosity, but yes, I can turn my android phone into a hair dryer if it takes $35 of auxilary equipement.
I'd love to see that actually... Most hair driers are very power hungry. 2kW is not uncommon (at least here where standard voltage is 240V). Achieving substantial amount of drying from a mobile phone battery would be quite a feat of engineering.