Cris.lynx
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Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 8:03 am

Hi guys,

I bought my Pi model B a few months after it came out for the purpose of connecting it to this portable TV:
http://www.radiomuseum.org/r/roadstar_tv_412_e.html

The Pi worked and still does, just not with the TV. I took both gadgets to a friend who said that it must be the Video frequency of the Pi which isn't compatible with the TV's.

My laptop just broke so I'm extra motivated to revisit the project.
Does anyone know how to change the Video frequency output of the Pi?

Edit:
thanks to user jdb - http://www.produktinfo.conrad.com/daten ... TV_412.pdf
Last edited by Cris.lynx on Wed Oct 26, 2016 5:15 am, edited 1 time in total.

fruitoftheloom
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Re: Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 9:07 am

Cris.lynx wrote:Hi guys,

I bought my Pi model B a few months after it came out for the purpose of connecting it to this portable TV:
http://www.radiomuseum.org/r/roadstar_tv_412_e.html

The Pi worked and still does, just not with the TV. I took both gadgets to a friend who said that it must be the Video frequency of the Pi which isn't compatible with the TV's.

My laptop just broke so I'm extra motivated to revisit the project.
Does anyone know how to change the Video frequency output of the Pi?
IF you are using the TRRS4 Video / Audio Output on the Raspberry Pi it is either PAL or NTSC:

https://en.wikipedia.org/wiki/Composite_video

You must have the correctly wired TRRS4 Cable as well:

http://www.raspberrypi-spy.co.uk/2014/0 ... video-jack
adieu

My other Computer is an Asus CS10 ChromeBit running Chrome Operating System.
HP Envy 4500 Wireless Printer supported by HPLIP software in Raspbian Buster.
Raspberry Pi Model 2B v1.1

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RaTTuS
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Re: Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 9:51 am

if it[ the TV] does not have a rca / or hdmi connector then your on to a loosing battle
How To ask Questions :- http://www.catb.org/esr/faqs/smart-questions.html
WARNING - some parts of this post may be erroneous YMMV

1QC43qbL5FySu2Pi51vGqKqxy3UiJgukSX
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pksato
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Re: Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 10:47 am

Hi,
If you TV is exact same model of radiomuseum, the have a video input on back.
Connect RPi video out (RCA) to video input on TV. Change AV/TV switch to AV.
TV still working? Tune open air analog TV station (if have one)? Or if on all digital region, TV screen show noise?

Next, need to for raspberry firmware to use composite video output, modify config.txt, add or changing these lines:

Code: Select all

hdmi_ignore_hotplug=1
sdtv_mode=0
If get a unstable image, change sdtv_mode to 2.

If using noobs, try key 3 or 4.

If TV have only antenna input, need a RF modulator. Or modify TV circuit to accept CBS Video.

jdb
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Re: Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 1:22 pm

There's little chance of this working.

http://www.produktinfo.conrad.com/daten ... TV_412.pdf

1. The TV only has an RF input port. The Pi's video output is from 0 to 8MHz (baseband CVBS) whereas the TV expects VHF/UHF input.
2. It looks like the model in question is for an old television standard which isn't PAL. Even if you got the Pi's output upmixed via one of those old RF modulator boxes, it's unlikely that either NTSC or PAL will work.
Rockets are loud.
https://astro-pi.org

fruitoftheloom
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Re: Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 1:40 pm

jdb wrote:There's little chance of this working.

http://www.produktinfo.conrad.com/daten ... TV_412.pdf

1. The TV only has an RF input port. The Pi's video output is from 0 to 8MHz (baseband CVBS) whereas the TV expects VHF/UHF input.
2. It looks like the model in question is for an old television standard which isn't PAL. Even if you got the Pi's output upmixed via one of those old RF modulator boxes, it's unlikely that either NTSC or PAL will work.
In the pictures it shows AV Inputs ????
adieu

My other Computer is an Asus CS10 ChromeBit running Chrome Operating System.
HP Envy 4500 Wireless Printer supported by HPLIP software in Raspbian Buster.
Raspberry Pi Model 2B v1.1

jdb
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Re: Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 3:02 pm

Depends what model it is - it seems the TV-412E model looks like it has a video input port and audio (output?) port. OP should confirm with photos of their actual unit.
Rockets are loud.
https://astro-pi.org

drgeoff
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Re: Pi 1 Model B Video compatibility issue

Mon Oct 24, 2016 4:44 pm

jdb wrote:2. It looks like the model in question is for an old television standard which isn't PAL. Even if you got the Pi's output upmixed via one of those old RF modulator boxes, it's unlikely that either NTSC or PAL will work.
Yes it will. This is a 625 line model. The additional 'France' circuit is for the different intercarrier sound frequency and the positive video modulation of their System L. (Nothing to do with the old 819 line system.) See the section 'ITU Standards' at https://en.wikipedia.org/wiki/Broadcast ... on_systems

However, bearing in mind that this is a monochrome set with a small screen and likely to have poor (and inconsistent across the screen) focus, using it to do anything textual with a RPi will probably lead to severe disappointment with the result.

Cris.lynx
Posts: 3
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Re: Pi 1 Model B Video compatibility issue

Wed Oct 26, 2016 5:57 am

fruitoftheloom wrote: IF you are using the TRRS4 Video / Audio Output on the Raspberry Pi
I have a Pi Model B, it has the composite video output socket.
pksato wrote: If your TV is the exact same model as radiomuseum's, that has a video input on the back:
Connect RPi video out (RCA) to video input on TV. Change AV/TV switch to AV.
TV still working? Tune open air analog TV station (if have one)? Or if on all digital region, TV screen show noise?

Next, need to for raspberry firmware to use composite video output, modify config.txt, add or changing these lines:

Code: Select all

hdmi_ignore_hotplug=1
sdtv_mode=0
If get a unstable image, change sdtv_mode to 2.

If using noobs, try key 3 or 4.
TV still works. I can even watch two channels.
When switching the AV/TV to AV while plugged in to a powered-up Pi, the screen is blank.

I will try your code as soon as I can.
jdb wrote:Depends what model it is - it seems the TV-412E model looks like it has a video input port and audio (output?) port. OP should confirm with photos of their actual unit.
My TV looks exactly like the first three pictures on radiomuseum. It has a video and audio input socket.
http://www.radiomuseum.org/r/roadstar_tv_412_e.html
drgeoff wrote: This is a 625 line model. The additional 'France' circuit is for the different intercarrier sound frequency and the positive video modulation of their System L. (Nothing to do with the old 819 line system.) See the section 'ITU Standards' at https://en.wikipedia.org/wiki/Broadcast ... on_systems

However, bearing in mind that this is a monochrome set with a small screen and likely to have poor (and inconsistent across the screen) focus, using it to do anything textual with a RPi will probably lead to severe disappointment with the result.
I am aware that I probably won't be able to use it to do any work. I want to make it to see what I could do with it. :D
I thank everyone for their replies :)

Cris.lynx
Posts: 3
Joined: Mon Oct 24, 2016 7:44 am

Re: Pi 1 Model B Video compatibility issue

Thu Oct 27, 2016 8:15 am

Alright, here's what I did today:

First, I plugged-in the TV and tuned it to a channel to test if it works. I switched the AV/TV to AV and connected it to the Pi with a composite video cable.
Image

Then I downloaded NOOBS Lite, followed the included instructions by formating a 4GB SD card with the SD Card Formatter software I downloaded from SDcard.org. I extracted the contents of the NOOBS .zip file to the SD card.

I inserted the SD card into the Pi and connected the Pi to the my microUSB charger.
Image

It is important to note that the TV's screen became brighter as the Pi booted up. I disconnected the USB keyboard from the computer and connected it to the PI. I pressed 3 and 4 several times on both the Main Typing Keypad and the Numeric Keypad. I observed no change on the TV screen.

I powered my Pi with both a 5V 0.85A USB charger (pictured bellow) and the computer's USB port. I have another USB charger but I fear the 5.2V and 1.35A would be too much for the Pi.
Image

This is how the backside of the TV looks like:
Image

Does it make sense to try with another operating system?

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Burngate
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Re: Pi 1 Model B Video compatibility issue

Thu Oct 27, 2016 9:58 am

Cris.lynx wrote:... I powered my Pi with both a 5V 0.85A USB charger (pictured bellow) and the computer's USB port. I have another USB charger but I fear the 5.2V and 1.35A would be too much for the Pi.
Does it make sense to try with another operating system?
The USB spec stipulates <5.25v so 5.2v should be fine. The Pi will only take what it needs, so 1.35 should also be fine.

You could try the Raspbian image, loading it using Win32disk.
However, using NooBs, note that (from the troubleshooting sticky)
Booting to NOOBS works a bit differently: it will always output a HDMI signal, even if you have nothing connected to the HDMI port, unless you press one of the numerical keys, 3 (PAL) or 4 (NTSC), to switch to a composite video output mode.
You don't say you pressed "3", so bearing in mind how fully you've described what you did, I'm guessing you didn't do that.

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