How to get teletext from an RPi -- for complete idiots

[TonyDuell]

Can somebody point me to explicit instructions to generate a teletext signal using an Raspberry Pi?

Something on the level of :

1)Buy this type of RPi
2)Put these files onto an SD card of this size
(OR, write this image onto an SD card using this utility)
3) Stick the SD card into the RPi, power it up, and take the signal from the composite video socket here.

I can't easily (if at all) connect an RPi to the internet which rules out some ways of doing it. On the other hand, there should be a way to do it 'standalone'

[kellys_eye]

Here's a website that takes you through it step by step:

https://www.raspberrypi.com/news/cre...etext-service/

[TonyDuell]

Thanks, but a critical step in that procedure involves connecting the RPi to the internet and downloading the software. Which as I said is impossible for me.

There must be a way to do it standalone.

[SiriusHardware]

I think I probably know the answer, but do you have a modern smartphone? (I'm assuming you do have some means by which you access the internet to access this forum, although it's possible that you may use the computers in your local library / internet cafe).

Most if not all smartphones have the ability to function as a wi-fi 'hotspot' or 'Mi-Fi' which uses the phone as a bridge between any wifi equipped device and the internet, via the cellular network. It's just a feature that you have to turn on and most (possibly not all) SIM providers support it. Later models of Raspberry Pi come with wifi built onto the PCB, earlier models required something like a USB 'Nano' wifi adaptor to be plugged into one of the USB ports.

If the above is a dead end:-

Someone with Internet access and a similar R-Pi model to yours could prepare an SD card with the standard OS image and then download the required software onto it, test it, then send you the SD card to put in your own Raspberry Pi.

Possible complications: Old / Early Raspberry Pis used a standard sized SD card, later / current ones use a micro-SD sized card so there would need to be some agreement on the size, Raspberry Pi model, etc.

Output is via the composite output on the R-Pi, older/larger Pi models have an RCA composite-video output socket onboard, smaller models such as the Raspberry Pi Zero do also have composite-out but it is only supplied on a pair of solder pads to which you would have to solder a flying lead with an RCA socket on the end.

Another consideration is that if there is any 'live' teletext to be found anywhere these days it is most likely on the internet, so unless you just plan to use the project to display fixed pages of teletext (ie, as a teletext test signal generator) then you might end up needing to connect it to the internet anyway.

[kellys_eye]

Originally Posted by TonyDuell

Thanks, but a critical step in that procedure involves connecting the RPi to the internet and downloading the software.

Forgive me for stating the obvious but to load and run a Pi OS you have to go through the configuration which also sets up your internet connection (wifi) so you'd have access to download software by default.

Unless I'm missing something?

[SiriusHardware]

Not all Pis have built in wifi (The original Pi Zero (As opposed to the Pi Zero W) does not, nor do the Raspberry Pi 1 and 2) and there is no automatic assumption that the Pi will be connected via Ethernet (where the pi has ethernet) so I don't think connection to the internet is actually mandatory during the setup process.

Obtaining an image to flash the SD card with the OS with is however quite difficult without the internet, unless you buy a pre-imaged SD card from one of the several UK Raspberry Pi resellers.

[hamid_1]

I've successfully used a Raspberry Pi to generate teletext. I chose the original Raspberry Pi 1 with separate composite video phono socket. It's long since been discontinued but can be obtained secondhand. You can also use the newer models, some of which have built-in wi-fi, but you'll need a composite video cable or you'll have to solder wires onto the board for composite video.

It's rather awkward to set up without an internet connection. Typing in the command to install teletext actually downloads a script file from the internet. This goes off and downloads then installs all the necessary files. For this to work, your Raspberry Pi must be connected to the internet. Once installed, the teletext pages can be displayed offline, though if your Raspberry Pi has an internet connection, it can update the pages with the latest information. In offline mode, the teletext pages will still be transmitted, but the information in them will not get updated, so you'll see last week's news and weather if you haven't been online since then. This may not be a problem for you, of course.

As said, you can turn a modern mobile phone into a wi-fi 'hotspot' by switching on that feature in the settings. This is how I'm accessing the internet right now. I don't currently have fixed-line broadband at my house. The phone produces a wi-fi signal just like a wireless router with fixed-line broadband, except that it's mobile and can be used wherever there's a mobile phone signal. Simply connect your PC or Raspberry Pi to your mobile wi-fi and off you go! If you use this method, there are a few things to bear in mind:

The Raspberry Pi 1 does not have built-in wi-fi. There are two versions of the Raspberry Pi 1 - 'B' which has wired ethernet and 'A' which does not. Either of them will work for teletext. To use wi-fi you'll need to plug in a USB wireless network adapter that's compatible with Raspberry Pi OS. I got lucky and tried a random USB wi-fi adaptor that I had lying around. It worked straightaway without needing any drivers. I guess a large number of wi-fi adapters are supported these days.

Secondly, if you are using the mobile network to access the internet, be aware of how much data allowance is included in your plan and the costs of going over it, which can be very high. Downloading a Raspberry Pi OS image could take a couple of gigabytes, and downloads can be slow at times. You can get Pay As You Go SIM cards from mobile phone shops or newsagents / convenience stores. Typically when you buy £10 of credit, you can get a bundle of call-time minutes and several gigabytes of data valid for one month with no commitment to pay anything more. This should be enough to set up a Raspberry Pi with teletext.

If you get stuck I can make you a copy of my Raspberry Pi 1 full-size SD card with teletext software already installed. I'd have to send it to you by post though, the file will be too big to attach here. Also I can't guarantee that it will work on a newer Raspberry Pi model.

Once you have the Raspberry Pi with teletext software up and running, you either connect the composite video from the Raspberry Pi directly into your TV's AV input and select AV mode on your TV, or connect the composite video to a UHF RF modulator connected to the aerial socket on your TV. Tune the TV into the RF modulator's signal. You should see the Raspberry Pi picture on your TV. Select the telextext service you want to run on the Raspberry Pi teletext software (currently there's Ceefax and Teefax). Press the TEXT button on your TV remote control and enjoy teletext!

[SiriusHardware]

Tony has explained elsewhere that his internet facilities at home are extremely limited. I understand that his current Pi is one of the older ones (Pi 2?), ie, with composite out available on a single RCA connector and the large sized SD card holder, but it would be good if Tony could definitely confirm this.

I think what would probably help him most would be an actual SD card already imaged with a working teletext setup on it. Card image files tend to be quite large (several Gigabytes) and that will be too much.