In the US it's generally LEGAL to listen to police calls, BUT Listening to cellphone signals is NOT. However. People in the 1980s-90s could hear the then standard (AMPS) analog cell traffic with a...TV set! (Upper channels of the UHF TV band).
I find it curious that when they as the government have access to the entire spectrum they choose a frequency that interrupt existing services. No such issues have been seen in Norway when the tetra network was rolled out.
The only interruption to existing services here was the TV reception, caused not by TETRA (transmitting well within limits of it's spectrum allocation) but by the often cheap and nasty mast head amplifiers which are usually quite broad banded and have far too high a gain figure for the required application. This in turn pushes the TV front end too hard and causes out of band signals to present as interference. It was/is the consumer tech that is at fault here and not the frequency or transmission type chosen by Airwave.
This kinda reminds me of the 2.4GHz DSS (Digital Spread Spectrum) that Panasonic came out with for their wireless home phones. This was worse than a leaky microwave as it spread the signal over multiple 2.4GHz frequency bands. It absolutely wrecked havoc with 2.4GHz Wi-Fi Networking!!! 😂
Most Tetra variants are hackable now although mostly not in real time but can be with substantial post processing which makes any information gained out of date. Typically takes 8 to 40 minutes with modern GPUs 😂
Memories of circa 1997 when Channel 5 TV launched. In areas where Channel 5 was operating on UHF channel 35 or 37, it was necessary to visit homes to check that video recorders or satellite receivers (which frequently used channel 36 to send a signal to the TV) would not suffer interference. A specially made signal generator was used, and if interference occurred, it was necessary to retune the modulator, or fit a notch filter. This had to be done BEFORE Channel 5 went on air, and at their expense. I was one of the army of Retuners employed for this task - a job I found very enjoyable and (being on a commission / bonus scheme) quite lucrative! ☺
In the US we used channel 3 and 4 to attach external devices. Usually there was a switch to choose between them. I also had a different device that let me choose from a large range of channels. At one point I had channel 3, 4, and 14 attached to different devices and I ran the signals to every TV in our home.
I once had in my collection a Grundig *VIDEO 2000* VCR that had been retuned as it had one of those stickers. Yeah, someone was still using V2000 in 1997! Also ISTR there was one particular model of Thomson VHS VCR that had a tuner but no RF modulator, so you connected it to the TV only using the SCART connection. That caused a bit of confusion!
@@stickytapenrust6869 I've still got a strip of those stickers! We had to write the channel number they'd been retuned to, and it gave a number to call if there were any problems. There was a training video that, sadly, doesn't seem to be on TH-cam. The first part is about the retuning process, but it finishes with a rather amusing "Customer care: how NOT to do it" sequence. A scruffy retuner walks in although it's a child at the door, ignores the "fierce" dog, makes sexist remarks to the woman of the house, breaks things etc.
Hi man. This is SM4VFA in Sweden. We never had that problem. The Police here was on 79.4375 MHz in Avesta, Sweden. When they turned to Tetra it was whithout a problem man. The 300 MHz band in Sweden is kind of a sometimes a military band even. Best regards from SM4VFA. 73 de.
Interesting stuff. I always wondered how UHF and VHF TVs worked over the pond with 50Hrtz. The only thing we had interfere with TV signals were TV pirates jamming the signal occasionally which the local TV broadcast station would blame on malfunctions. But if you monitored the phreaking BBSs at the time you could find people bragging they were doing it.
What's the significance of '50Hrtz' (presumably you mean 50 Hz)? Fifty Hz is the UK mains frequency (as opposed to 60Hz in the US). You may be right that the mains frequency has been used to synchronise the timebase period in vintage CRT TVs in the past but actually designing for either 50Hz or 60Hz is not any real challenge. On top of that, in theory, the core materials of transformers (and CRT TVs had at least one pretty hefty one) may make them much more efficient at certain frequencies (and much less efficient aka a lot of heating loss at others) but in practice the behaviour of transformers run at either 50Hz or 60Hz was unimportant. Most importantly in terms of TV differences, American TVs used an analogue colour picture format known as NTSC (also used in the Americas generally and in Japan) whereas European TVs (including UK ones) used an entirely different format known as PAL. A third format called SECAM is in use in France as well as Russia, China and many others. It's possible to make analogue colour TVs that could cope with all three formats (I had a beautiful little 5 inch Sony with this capability in the mid-1970s) so, you'll understand that 50Hz vs 60Hz really isn't any big thing, engineering wise, at all. BTW, practically everyone these days is watching digital LCD TVs so the whole mains frequency 'issue' is moot.
It probably didn't help that many Airwave transmitters were co-located on TV Relays around the country due to position of coverage, ensuring that your TV aerial is picking up both TV and Airwave at the same time....
That’s an interesting segment of the spectrum. Used by military forces of a very large county of NATO AND WORLDWIDE. In the States notch filters are used for the receivers and the best ones come from a company in Canada and are custom made to a specific frequency. For the transmitters of the use of multiple band pass filters in line towards the antenna with a circulator to the output of the transmitter placed in line before the filter cans. The circulator is a tuned device that will allow the selected frequency through while any other frequencies created through intermodulation or by co located frequencies from entering the transmitter and mixing and forming frequencies that could be amplified by the same transmitter and broadcast back out. Frequencies that are not of the selected frequency are shunted to a dummy load so as not to enter the transmitter. Wish I could show how a receiver multi coupler works as well as how a transmitter combiner system works. This might be a good video to make! I would venture to say that the installation of these systems lead up to the TVI many suffered from. In the states the burden would fall on the manufacturer of the equipment causing harmful interference.
As a radio amateur a neighbour came banging on the front door years ago, 1980's, and told my Dad I was causing interference to his t.v. He informed him that I was asleep in the front room in a chair. I wonder how many times it occurred after we moved. G4GHB.
When the Tetra antenna was switched on in my home town, I remember seeing this interference. Was probably around 500 yards line of sight from the transmitter. I didn't last long, maybe a couple of weeks and never saw it again.
In San Antonio years ago the NSA had to apologize because during on weekday morning they were doing signals test on the same band used by garage door remotes and many many people couldn't open their garage doors to go to work in NW SA (why they didn't open it manually is beyond me)
Amazing you posted this today. I have been following your videos for a long time and only subscribed today. I was going to email you a question today. But you have just answered it in the video. I do have radio equipment been a hobby for 40 years. Now I have cctv at home ( A wired system) and a strange happened 2 weeks ago. I had the police at my door asking if I had any footage of some incident that had happened early on that day. It was late at night when they called and I said I would have a look at the footage the next morning. Now the wierd part is I have footage of the police car pulling up then total video loss. It resumed after they left. As I was talking to one officer the other was on the radio most of the time. Just seems more than coincident dont you think. Sorry for the long comment.
Sounds like more than a coincidence. If it was a wired camera I would have guess someone used a jammer. Since it was a wired camera, could they have disconnected the wiring to the camera? Seems like it would be odd they would reconnect it, but maybe that was part of a thorough operation. Maybe the call to you was to make sure you didn't have any good footage.
@@lostangeles4476 Thanks for the reply. All 4 cameras wired through walls no visible wires. It is cheap and nasty coax that came with the kit. I am thinking an RFI issue. The footage went green and pink just before it went black. The DVR recorder must of rebooted as there was 3 minutes time missing also. It was not a serious crime and I did have footage of the incedent, Just none of the police at my door. I might start monitoring frequencies for signal strenght in that range. Its got to be the portable uplinks. Not sure of the bandwidth they transmit on. More learning needed.🧐
The block of flats i used to live in was right next to multiple 4g masts, i needed a filter for my tv at the time. There were some mast upgrades that made half of the freeview channels disappear, i was told about a free filter i could apply for through a leaflet in the post
Tetra is using frequencies equal to cable band channels S30 to S33. Over the air this is used by radio only. I don't know how much cable tv coverage UK had in the year 2000. I guess it was the only most common way to get television rather than using antenna. If this was with over antenna, the Tetra system must have had a massive RF leaking close to the transmitter of Tetra. This was never a problem in Iceland. Looking over old news articles in Iceland I can't find a single mention of interference from Tetra in Iceland. Cable tv use in Iceland around the year 2000 was minimal and most people got their signal over the antenna.
I remember seeing those effects when tuning around but it didn't cause me any problems & i didnt know the source of those emissions. Not much tv spectrum left now with chunks being taken away for mobile phones.
To be fair, stress is bad for health and nothing stresses some people out more than missing "their stories" aka soap operas. Therefore, it is bad for their health. 😂
380 to 400 Mhz right? Nice in the UHF band, but thats just a few tv chanels. Harmonics or problems whit high gain TV antenna oversaturated. Even 144Mhz repetition system can haw problems from TV antennas, reflecting out or even oscilating on the band from high gain and acidental change in dipole elements. So it goes both ways
Similar issues in Australia with POCSAG pagers. There’s some transmitters on the hill above my home and they do cause sporadic glitches on digital TV. Our DTV signals in Australia are on VHF in most state capital cities. The pagers use 148-149mhz so also a pain on the 2M ham band
That could be a faulty transmitter. We had one in our town that would drift towards the end of a 16 page block. Slewing across the 2m band from 154Mhz. They ignored our complaints until we got the FCC involved.
I once realised how i could hack most digital TVs and because I held a reasonably significant position in the digital TV industry, I raised the concern. But the attack wasn't particularly simple, so it wasn't mitigated. I won't explain the process but it could be dramatic if actually exploited.
Off topic but I just picked up a powerful smanchester pirate on 87.7 FM Rds says 'Ruby 87.5' as do the station idents but you want to tune to 87.7 to hear it. Station of the same name was on 87.5 in August this year though I only heard it on a couple of days before it seemed to go off air.
Hi Lewis, Do I need a TV license to receive television sound? This question came to mind when watching this video because I had such an personal experience of this. Ok, it was back in the late 1960s when I lived in Elmers End, south London and the Crystal Palace transmitter mast/tower was clearly visible from my sitting room window. BBC TV sound was easily received on the loudspeaker wires of my stereo system. The TV signals, at that time were analogue VHF and very strong due to the short distance. My audio amplifier and wiring was now acting as a aerial and receiver for TV signals. Have I now admitted an offence as per the Wireless Telegraphy Act at that time? I still have that same amplifier etc. and it still works but no TV sound these days. The Beckley transmitter (went digital in 2011) is a lot further away from me. “ I’m in the front room watching Columbo” (from TV Licensing TV advert) 🤣 Best wishes from (a secret location) Oxfordshire 73s
Tetra TEA2 encryption is the main one used by airwave, other forms cryptography exist. If ever the key was released, history would repeat it's self, listening on the police again.
TV illegally receiving police signals.
“Arrest that man!!”
@@Vtarngpb… And double his TV Tax! 😂
Exactly ~
Didn't really have a choice as the transmitters were to blame
In the US it's generally LEGAL to listen to police calls, BUT Listening to cellphone signals is NOT. However. People in the 1980s-90s could hear the then standard (AMPS) analog cell traffic with a...TV set! (Upper channels of the UHF TV band).
Imagine paying for a tv license, and still not being entitled to it's use
@@c0ldsh0w3r back in the 90's, we had Comms coming over tv, when the dribble was close by.
It's only a matter of time before Baofeng bring out a Tetra AirWave receiver... and we all end up before the Magistrates! 😂😂😂😂
For legal reasons, I'm not sayin I'd buy one... but....
I find it curious that when they as the government have access to the entire spectrum they choose a frequency that interrupt existing services. No such issues have been seen in Norway when the tetra network was rolled out.
The only interruption to existing services here was the TV reception, caused not by TETRA (transmitting well within limits of it's spectrum allocation) but by the often cheap and nasty mast head amplifiers which are usually quite broad banded and have far too high a gain figure for the required application.
This in turn pushes the TV front end too hard and causes out of band signals to present as interference.
It was/is the consumer tech that is at fault here and not the frequency or transmission type chosen by Airwave.
@@AdamSWL
Absolutly right 👍👍👍
This kinda reminds me of the 2.4GHz DSS (Digital Spread Spectrum) that Panasonic came out with for their wireless home phones. This was worse than a leaky microwave as it spread the signal over multiple 2.4GHz frequency bands. It absolutely wrecked havoc with 2.4GHz Wi-Fi Networking!!! 😂
The problem with ISM bands 😂
Most Tetra variants are hackable now although mostly not in real time but can be with substantial post processing which makes any information gained out of date.
Typically takes 8 to 40 minutes with modern GPUs 😂
Memories of circa 1997 when Channel 5 TV launched. In areas where Channel 5 was operating on UHF channel 35 or 37, it was necessary to visit homes to check that video recorders or satellite receivers (which frequently used channel 36 to send a signal to the TV) would not suffer interference. A specially made signal generator was used, and if interference occurred, it was necessary to retune the modulator, or fit a notch filter. This had to be done BEFORE Channel 5 went on air, and at their expense.
I was one of the army of Retuners employed for this task - a job I found very enjoyable and (being on a commission / bonus scheme) quite lucrative! ☺
Lol I can remember the TV man coming around and switching Channel 5 on! I was about 12. Mad how much has changed
I can remember having to turn the wee screw on the back of my Hinari VCR.
In the US we used channel 3 and 4 to attach external devices. Usually there was a switch to choose between them. I also had a different device that let me choose from a large range of channels. At one point I had channel 3, 4, and 14 attached to different devices and I ran the signals to every TV in our home.
I once had in my collection a Grundig *VIDEO 2000* VCR that had been retuned as it had one of those stickers. Yeah, someone was still using V2000 in 1997!
Also ISTR there was one particular model of Thomson VHS VCR that had a tuner but no RF modulator, so you connected it to the TV only using the SCART connection. That caused a bit of confusion!
@@stickytapenrust6869 I've still got a strip of those stickers! We had to write the channel number they'd been retuned to, and it gave a number to call if there were any problems.
There was a training video that, sadly, doesn't seem to be on TH-cam. The first part is about the retuning process, but it finishes with a rather amusing "Customer care: how NOT to do it" sequence. A scruffy retuner walks in although it's a child at the door, ignores the "fierce" dog, makes sexist remarks to the woman of the house, breaks things etc.
"Ofcom were not much help either...". Where have I heard that before?
Hi man. This is SM4VFA in Sweden. We never had that problem. The Police here was on 79.4375 MHz in Avesta, Sweden. When they turned to Tetra it was whithout a problem man. The 300 MHz band in Sweden is kind of a sometimes a military band even. Best regards from SM4VFA. 73 de.
Interesting stuff. I always wondered how UHF and VHF TVs worked over the pond with 50Hrtz. The only thing we had interfere with TV signals were TV pirates jamming the signal occasionally which the local TV broadcast station would blame on malfunctions. But if you monitored the phreaking BBSs at the time you could find people bragging they were doing it.
What's the significance of '50Hrtz' (presumably you mean 50 Hz)? Fifty Hz is the UK mains frequency (as opposed to 60Hz in the US). You may be right that the mains frequency has been used to synchronise the timebase period in vintage CRT TVs in the past but actually designing for either 50Hz or 60Hz is not any real challenge. On top of that, in theory, the core materials of transformers (and CRT TVs had at least one pretty hefty one) may make them much more efficient at certain frequencies (and much less efficient aka a lot of heating loss at others) but in practice the behaviour of transformers run at either 50Hz or 60Hz was unimportant. Most importantly in terms of TV differences, American TVs used an analogue colour picture format known as NTSC (also used in the Americas generally and in Japan) whereas European TVs (including UK ones) used an entirely different format known as PAL. A third format called SECAM is in use in France as well as Russia, China and many others. It's possible to make analogue colour TVs that could cope with all three formats (I had a beautiful little 5 inch Sony with this capability in the mid-1970s) so, you'll understand that 50Hz vs 60Hz really isn't any big thing, engineering wise, at all. BTW, practically everyone these days is watching digital LCD TVs so the whole mains frequency 'issue' is moot.
There’s absolutely no relation whatsoever between the timebases (frame and line frequencies) with the RF band used. That’s how they worked…
It probably didn't help that many Airwave transmitters were co-located on TV Relays around the country due to position of coverage, ensuring that your TV aerial is picking up both TV and Airwave at the same time....
Well done Lewis. Your research is top notch!
That’s an interesting segment of the spectrum. Used by military forces of a very large county of NATO AND WORLDWIDE.
In the States notch filters are used for the receivers and the best ones come from a company in Canada and are custom made to a specific frequency. For the transmitters of the use of multiple band pass filters in line towards the antenna with a circulator to the output of the transmitter placed in line before the filter cans. The circulator is a tuned device that will allow the selected frequency through while any other frequencies created through intermodulation or by co located frequencies from entering the transmitter and mixing and forming frequencies that could be amplified by the same transmitter and broadcast back out. Frequencies that are not of the selected frequency are shunted to a dummy load so as not to enter the transmitter. Wish I could show how a receiver multi coupler works as well as how a transmitter combiner system works. This might be a good video to make! I would venture to say that the installation of these systems lead up to the TVI many suffered from. In the states the burden would fall on the manufacturer of the equipment causing harmful interference.
Hooray! Thanks man! This is great! Sorry for any offense on the previous video.
So, the harmful interface was all down to, "Little Mo?"
Who'd have guessed. 😀
As a radio amateur a neighbour came banging on the front door years ago, 1980's, and told my Dad I was causing interference to his t.v.
He informed him that I was asleep in the front room in a chair.
I wonder how many times it occurred after we moved.
G4GHB.
All passed by my event horizon - must have been down the pub ?
Thanks RM. Always the coolest Stuff*****
When the Tetra antenna was switched on in my home town, I remember seeing this interference. Was probably around 500 yards line of sight from the transmitter. I didn't last long, maybe a couple of weeks and never saw it again.
We never had any interference but we did have that TV!
In San Antonio years ago the NSA had to apologize because during on weekday morning they were doing signals test on the same band used by garage door remotes and many many people couldn't open their garage doors to go to work in NW SA (why they didn't open it manually is beyond me)
Amazing you posted this today. I have been following your videos for a long time and only subscribed today. I was going to email you a question today. But you have just answered it in the video. I do have radio equipment been a hobby for 40 years. Now I have cctv at home ( A wired system) and a strange happened 2 weeks ago. I had the police at my door asking if I had any footage of some incident that had happened early on that day. It was late at night when they called and I said I would have a look at the footage the next morning. Now the wierd part is I have footage of the police car pulling up then total video loss. It resumed after they left. As I was talking to one officer the other was on the radio most of the time. Just seems more than coincident dont you think. Sorry for the long comment.
Sounds like more than a coincidence. If it was a wired camera I would have guess someone used a jammer. Since it was a wired camera, could they have disconnected the wiring to the camera? Seems like it would be odd they would reconnect it, but maybe that was part of a thorough operation. Maybe the call to you was to make sure you didn't have any good footage.
@@lostangeles4476 Thanks for the reply. All 4 cameras wired through walls no visible wires. It is cheap and nasty coax that came with the kit. I am thinking an RFI issue. The footage went green and pink just before it went black. The DVR recorder must of rebooted as there was 3 minutes time missing also. It was not a serious crime and I did have footage of the incedent, Just none of the police at my door. I might start monitoring frequencies for signal strenght in that range. Its got to be the portable uplinks. Not sure of the bandwidth they transmit on. More learning needed.🧐
If this had happened in the US they would have impeached the government!🤣🤣🤣🤣
The block of flats i used to live in was right next to multiple 4g masts, i needed a filter for my tv at the time. There were some mast upgrades that made half of the freeview channels disappear, i was told about a free filter i could apply for through a leaflet in the post
Tetra may be my 'tinnitus'.
Tetra is using frequencies equal to cable band channels S30 to S33. Over the air this is used by radio only. I don't know how much cable tv coverage UK had in the year 2000. I guess it was the only most common way to get television rather than using antenna. If this was with over antenna, the Tetra system must have had a massive RF leaking close to the transmitter of Tetra. This was never a problem in Iceland. Looking over old news articles in Iceland I can't find a single mention of interference from Tetra in Iceland. Cable tv use in Iceland around the year 2000 was minimal and most people got their signal over the antenna.
380 to 400 is military airband aaa, well as" tetra
Imagine having to pay a fee to watch OTA television 😂
Well-done on the interference re-enactment. And for using some other images too. I like your drone videos, but it's cool to see something else too.
Typical arrogance from the perpetrators here. Imagine if it was private individuals causing the interference...
Don't tell anyone that the old crt screens were firing an electron gun at the viewer the whole time they watched. :O)
I remember seeing those effects when tuning around but it didn't cause me any problems & i didnt know the source of those emissions. Not much tv spectrum left now with chunks being taken away for mobile phones.
Great reporting. Impeccable.
To be fair, stress is bad for health and nothing stresses some people out more than missing "their stories" aka soap operas. Therefore, it is bad for their health. 😂
380 to 400 Mhz right?
Nice in the UHF band, but thats just a few tv chanels.
Harmonics or problems whit high gain TV antenna oversaturated.
Even 144Mhz repetition system can haw problems from TV antennas, reflecting out or even oscilating on the band from high gain and acidental change in dipole elements.
So it goes both ways
No tv at 380 to 400 it's still military airband
Similar issues in Australia with POCSAG pagers. There’s some transmitters on the hill above my home and they do cause sporadic glitches on digital TV. Our DTV signals in Australia are on VHF in most state capital cities. The pagers use 148-149mhz so also a pain on the 2M ham band
That could be a faulty transmitter. We had one in our town that would drift towards the end of a 16 page block. Slewing across the 2m band from 154Mhz. They ignored our complaints until we got the FCC involved.
I once realised how i could hack most digital TVs and because I held a reasonably significant position in the digital TV industry, I raised the concern.
But the attack wasn't particularly simple, so it wasn't mitigated. I won't explain the process but it could be dramatic if actually exploited.
Off topic but I just picked up a powerful smanchester pirate on 87.7 FM
Rds says 'Ruby 87.5' as do the station idents but you want to tune to 87.7 to hear it.
Station of the same name was on 87.5 in August this year though I only heard it on a couple of days before it seemed to go off air.
Listening mate thanks!
No way lol that's mad. Popo ruining my friday evening Red Dwarf, Fast Show, Harry Enfield pre rave viewing!
TVI on EastEnders LOL 😄cheers for video Lewis 73
Hi Lewis,
Do I need a TV license to receive television sound? This question came to mind when watching this video because I had such an personal experience of this. Ok, it was back in the late 1960s when I lived in Elmers End, south London and the Crystal Palace transmitter mast/tower was clearly visible from my sitting room window. BBC TV sound was easily received on the loudspeaker wires of my stereo system. The TV signals, at that time were analogue VHF and very strong due to the short distance. My audio amplifier and wiring was now acting as a aerial and receiver for TV signals. Have I now admitted an offence as per the Wireless Telegraphy Act at that time? I still have that same amplifier etc. and it still works but no TV sound these days. The Beckley transmitter (went digital in 2011) is a lot further away from me. “ I’m in the front room watching Columbo” (from TV Licensing TV advert) 🤣
Best wishes from (a secret location) Oxfordshire 73s
There’s something fishy about this Tetra story. 🤣
Cool to see the hack rf h4m here would definitely love to see you make a full video on the device itself
i get a lot of mirroring mixing products from all the TETRA here in Norway, it it just saturates all SDRs. do a video on tetraburst ;)
6:47 - that car is reversing a bit sharpish. Must be on Red Dwarf’s Backwards world.
I am sure the BBC license police will help you fix your TV problems!
Well I just hope Tetra never interferes with my reruns of Rumpole of the Bailey! 🙂
"Ofcom weren't very helpful" Nothing new there then.
Would be better with your silly studio lights continually reflecting in the TV screen.
I'd respond in TETRA but I do not have enough comments to fill all four timeslots.
Sorry Lewis.
Hey i have a question, is it legal to use a ubc69xlt-2 in the netherlands
It depends on what you use it for and the laws in the Netherlands.
why is tetra interference ok but pirate radio interference not ok
Tetra been fully hacked since.
Not airwave
@RingwayManchester are you saying police use airwaves, I've always known they went tetra around 400mhz.
The Police use airwave... it has not been hacked. It is not the same as the version of Tetra that was hacked recently.
Tetra TEA2 encryption is the main one used by airwave, other forms cryptography exist. If ever the key was released, history would repeat it's self, listening on the police again.
Never was disclosed why a Police Issue Tetra Handset was removed from a Property 30th June 2018 within an Evidence Bag. Amesbury Wiltshire 🤔
Not heard this one Richard? Can you elaborate?
@@RingwayManchesterSeek and You will Find the Images. Best Wishes Sir 😉👍