DM500 RF Modulator Problems

[vroom_buddy]

Has anybody had problems converting the SCART output from a Dreambox 500 into an RF signal?

I distribute the picture from my DM500 around the house using an RF network and up until now, I have used my old VHS video recorder to convert the SCART output into an RF signal. This works fine but it means that the video has to be turned on and tuned to the AV input. To make it simpler I recently purchased a Mercury ILS102 RF Modulator and although it works fine with my DVD and Freeview box, it does not work with the Dreambox. When I plug the Dreambox into it, I get some audio for a brief moment and then it switches off. Any ideas what might be wrong?

I am using the DW2.1 image on the DM500 and the output from the Dreambox is set to be PAL.

[max_gee]

try changing from rgb to cvbs in the dream menu n see if that helps

[vroom_buddy]

I've now tried that but it makes no difference.

I get the impression that there's some sort of electronic "cut-out" in the RF Modulator unit and it doesn't like the signal from the DM500. The reason I say this is that if I plug my DVD into it and then replace it with the DM500, I get 2-3s of audio before it cuts out. If I don't use the DVD first, I get nothing at all. It's as if once the "cut-out" is activated, it does not get reset until a "good" signal (from the DVD) is plugged into it again. I might be dreaming here but that's the impression I get.

[nivlem]

is the picture you briefly see, low level contrast or normal to bright?
if it were low this could be why you loose the signal.

<--nivlem added 2 Minutes and 10 Seconds later...-->

old tv video games came with rf modulators, perhaps you might have such a thing tucked away in a cupboard/loft that you could adapt.

[vroom_buddy]

I don't actually get a picture at all. Just 2-3s of audio and the "threat" of a picture and then it stops.
It's a bit of a mystery to me because when I plug the Scart output from the Dreambox straight into the TV or the old VCR, it works fine and so I don't understand why this RF modulator is different.

[nivlem]

I don't actually get a picture at all. Just 2-3s of audio and the "threat" of a picture and then it stops.
It's a bit of a mystery to me because when I plug the Scart output from the Dreambox straight into the TV or the old VCR, it works fine and so I don't understand why this RF modulator is different.

Then try this!
Plug the Dream into the VCR, then pump the VCR output into the modulator, then see if the you get a picture, if you do then the fault lies between the Dream and the modulator, if you don't get a picture (just like before) then the fault is in the Modulator!
QED

<--nivlem added 1 Minutes and 9 Seconds later...-->

Correction to my text!

nivlem is on a distinguished road

Default
Quote:
Originally Posted by vroom_buddy View Post
I don't actually get a picture at all. Just 2-3s of audio and the "threat" of a picture and then it stops.
It's a bit of a mystery to me because when I plug the Scart output from the Dreambox straight into the TV or the old VCR, it works fine and so I don't understand why this RF modulator is different.
Then try this!
Plug the Dream into the VCR, then pump the VCR output into the modulator, then see if the you get a picture, if you don't then the fault lies between the Dream and the modulator, if you don't get a picture (just like before) then the fault is in the Modulator!
QED

<--nivlem added 1 Minutes and 5 Seconds later...-->

Shit I was right 1st time ...... ollocks!

[vroom_buddy]

Have now tried that and the modulator works well with the output from the VCR. Therefore, the problem lies somewhere between the Dreambox and the modulator. It can't be the cable because I use the same one to connect the Dreambox to the VCR. I can only assume that it must be something to do with the signal level and that the VCR handles it better than the modulator.

[nivlem]

Therefore by a process of elimination, you have proved that the modulator is sound and that in principle your hookup is sound. The only thing left is a dodgy Dreambox. The Dreambox electrical characteristics don't match the modulator, yet the VCR does.
So far so good!
Can you get a different modulator make, try that see it is a better match!

<--nivlem added 5 Minutes and 11 Seconds later...-->

look here for other rf modulators RF Modulators to Scart
or perhaps a video sender like..... Gigavideo 40/60/80

[vroom_buddy]

I borrowed a friend's Dreambox and got exactly the same problem. Looks like the electrical characteristics of the Dreambox output are not compatible with this particular RF modulator.

[tfspark]

I borrowed a friend's Dreambox and got exactly the same problem. Looks like the electrical characteristics of the Dreambox output are not compatible with this particular RF modulator.

How about the scart cable. Maybe you need a fully wired one?

[vroom_buddy]

I think I'm using a full Scart cable. All of the pins are in place. Whether they are all connected is another thing but it seems to be a standard cable. I have tried it with two other Scart cables and I get the same result, i.e. it works fine when I put the Dreambox output through the VCR but not through the RF modulator.

[vroom_buddy]

I've now put a Scart distribution amplifier (a Shinybow SB-3715) between the Dreambox and the modulator and it works fine. Seems as if the amplifier reads the Scart input without a problem and converts it into a Scart output which is suitable for the modulator. That's me sorted now. Thanks all.