DVD player to tv with no AV inputs

[Dan2]

i recently aquired a dvd player that i want to use for playing music - but i need some sort of a screen so i can browse folders of MP3 cd's etc. i have an old tv that would work great but it has no AV inputs - only the antennae connection.

a friend of mine has a video machine with an AV input, so he connected his dvd player to the video machine, and then it gets displayed on the tv through the antennae cable. i was wondering if it is easy to make a "converter" like the one in the video machine or if i should just try to get hold of an old video machine to do the converting for me.

 

[sandyK]

Dan2

Have a look at www.jaycar.com.au - keyword = modulator.
This will show you a few cheap alternatives that are probably available elsewhere too.
SandyK

 

[mag]

You can even use the UHF modulator of an old VCR.
You just need to know how to connect it but this is quite easy. Normally you need only to find out the power supply and the audio/video inputs.

 

[Dan2]

thanks for the replies - at least i know what i am looking for

so i guess the electronics are quite complex 'cos i would rather try to make something myself - only if it works out cheaper of course!!!

 

[dnsey]

Not complex, but pretty difficult to design and build, unless you have hf rf experience.

 

[mag]

If you want there is a chip called TDA5670 that does all the required functions.

In attached you will find a schematics of a small TV transmitter
using that chip. The output power is around +5dBm enough to cover a range of about 200m with a good antenna.
If you are not interested in raditing the signal you can just use the TDA5670 without the output PA stage.

If you are interested I can send you the complete project with gerber files but if you don't have experience with RF it will be quite impossible to make it work properly --> go for the VCR modulator, is much more easy

 

[Dan2]

Unfortunately i have not had any experience with RF

but thanks any way for the schematic.

and is there no way i can bypass the antennae connection on the tv???

 

[mag]

Of course there is a way but it is not so easy.

You need to remove the connection between the video demodulator and the video amplifier and feed the video composite signal at this point.

Normally thit is easier to be done in old TVs but harder on newer TV (BTW there is no need on the newer TV bacause they
already have the video input...).

The easiset way is an remain the VCR modulator or a commercial modulator that you can buy. The VCR modulator comes essentially for free..

 

[dnsey]

If you do decide to 'beak into' a TV set, be quite sure that you know what you're doing!

Many older sets (and some current ones) employ a 'live chassis' arrangement, which makes it very dangerous to just interface directly with the internal circuits without employing an isolator.

The modulator route is by far the easiest and safest.

 

[Dan2]

thanks for all your help - i really appreciate it!!