my problem:
my tv has built in digital, my dvd recorder can not see digital channels

The aerial going into the dvd player carries no digital signal, it's only when the second cable goes into the tv that it meets the in-built digital box.

So How can I get the dvd recorder to see my digital channels ?

thanks for any help

I have sumsung LE32R73B TV which has built in digitalbox

have just bought samsung DVD-HR737 dvd recorder

Welcome to CDF

Some TV's actually have an output specifically for this situation. My friend's Sony Brava (I think that's the model) has something like this but it doesn't look like yours has this functionality.

A separate digital receiver is your only option by the look of it.

As TimC has correctly pointed out, you'll need to buy a separate digital set-top box to feed signal to the DVD recorder, which is only equipped with an analogue tuner. Unfortunately, the highest "AV in" quality you can use is SVideo and RCA audio, which will give you an acceptable picture and a standard stereo soundtrack, not 5.1.