BATC Video Source Construction Details

[G8GKQ]

I have just finished boxing up my BATC Video Source as described in CQ-TV 270.

I used a second-hand Eddystone Die Cast Box type 7969 (the smallest in their range) measuring externally 92x28x32mm. I fixed a 7805 regulator to the lid, and mounted the Raspberry Pi Zero above it on spacers. This enables easy access to change the SD Card.

The card selection button and camera switch were mounted in the body of the box, with the camera module looking out of a hole in the "bottom". I used a salvaged flying lead to bring power in from a 2.1 mm barrel connector and take video out to a BNC socket. I tapped a thick piece of aluminium for the tripod thread and fixed this to the end of the box, and added stick-on rubber feet to the lid so that the unit does not scratch the bench when used off a tripod. Photos below.

Dave, G8GKQ

[G0NMY]

Nice project Dave,
What is it like temperature wise? does it get hot inside there or havent you run it for long periods?
I wonder if the board could be mounted upside down, and a small aluminium block touching the processor chip to act as a heat transfer block?
Just an idea, but great little project for a pi-zero i have kicking around.

[G8GKQ]

Hi

I don't foresee any heat problems at all. The RPi Zero only draws about 150 ma without the camera on and 190 ma with the camera. So max dissipation on the Zero is about 750 mW. So no need for a heatsink at all.

The 7805 regulator of course might end up dissipating 1.7W with a 13.8 v supply and the camera on - which is why it is bolted to the box lid.

Dave

[G4FRE]

Here is a photo of my version of the video source.

I knew I kept my original RPI model 1A for a reason. Now I Know what it is. It also has the benefit of having the video coming out of a phono connector rather than the illogically wired TRRS connector of later versions. A clue to it's age is the full size SD card!

The RPI and the 12V to 5.2V dc/dc converter fit nicely in the box. I didnt need the source to have a camera which saved some space

Dave
G4FRE

P1010001.JPG (1.49 MiB) Viewed 5649 times

[G8GKQ]

I've just published a new release of the software for the video source. The only functional change is that no text appears on the black screen displayed briefly when changing testcards. If you can put up with that text in the current build, there is no point in taking this new build.

There is a zipped image release, as well as a full build based on the latest (2020-12-02) version of Raspios. There is no update facility; the only option is to build a new card. Details here: https://github.com/BritishAmateurTelevi ... /vidsource

I do not anticipate any more new builds of the Video Source in the near future. Any enhancements will be first released in the "Video Source HD", which is currently a bunch of ideas in my head competing for my time against the Portsdown and the Ryde!

Dave, G8GKQ

[VK3IE]

Thanks Dave:
Great to see and use
Look forward to the HD Version maybe a .gif animator
Cheers
Rob

[G8GKQ]

I have added some information on customisation of the BATC Video Source on the wiki: https://wiki.batc.org.uk/BATC_Video_Source

Please feel free to add your own ideas there.

Dave, G8GKQ

[F1CJN_alain]

Hi Dave
I am using Filezilla or WinSCP to transfert files from py PC to the RPi Vidsource, connected as root.
To do that :

sudo nano etc/ssh/sshd_config
Then in the file uncomment and modify the line PermitRootLogin yes
Then: sudo passwd root
and enter your root password, and reboot.

Connect your PC using Winscp , root and your root password

Then you can transfert easily between for boot/testcard and your PC Windows
I am using a copy of testcard folder in my PC, so it is easy to modify

Have fun
Alain F1CJN

[f1faq]

What I do on my side, is that I make my mods in the vidsource directory and then use
"transfer.sh" to transfer files in boot/testcard directory.
But thank you Alain, I was looking how to gain access to root without success (sudo root su, etc... no way)
73 - Christian
F1FAQ

[g8gon]

hi i need some help pse.
my batc card worked ok with the pi , but it seemed i killed the camera somehow, new camera , new pi .....ok now.

then the next time i powered it up i get a line 112 error and some of the cards are missing and floating bits, misery..?? ordered another batc card and conned a software bod to look at the card seems that there were 3 picture files missing,, copied them to the old card from the new one, allok, both cards working in 2 pis ..!!!!

now after a few startups the same problem is happened to 2 cards and 2 pi anyone had the problem and any ideas whats going on?

cantc23a.sh: line112: ./: is a directory

by comparing the cards there were 3 picture files missing . g8gon specific files

any ideas appreciated? ...not software litterate alec