TV aerial

[craig51]

OK guys, just cant get my head round this one.

I have an TV aerialsocket in my livingroom. This is split into two as follows

1/ One goes straight upstairs to my bedroom, perfect.

2/ The other first of all goes into my cable box, then back out into the back of my hardrive recorder, then out again into the tv. This way buy the time the signal is at the tv, its also picked up the cable output, and also the hardrive. Pretty simple. BUT, what I want to do is watch cable on my tv upstairs, so need to somehow send the signal back to the original tv aerial point, then up the aeril to my room. How would you attempt this, and no i catn put down and cable from my cable box back to the aerial point.

Cheers.

 

[rssteve]

i think you need to be abit clearer. ideally you will come out of your hard drvier then into a splitter, one going to main tv and one back up other cable to bedroom. not sure if you have 2 cables at the tv point tho.

 

[Space cat]

There are at least two solutions to this problem:

1) Move the split point from the wall socket to the output of the cable box - or even the recorder. To do this you must be able to remove the bedroom cable from the splitter at the wall. Can you move the whole splitter? If not then you'll need a second splitter.

2) The cable box doesn't use the UHF signal arriving at it's input socket. It just adds its own output to it and sends it on down the line. Remove the cable from its input and put it into a splitter instead. Put the output from the cable box and the input to the recorder into the same splitter. This splitter has to work two ways. It must combine the cable output with the aerial signal to feed the recorder. It must also split the cable output to the TV and back to the aerial socket. The splitter on the wall will have to do the same.

Method two will only work if your splitters are symmetric. One of the simplest splitters consists of three resistors connecting the centre cores of the cables. You can use 25 ohms in a star network or 75 ohms as a delta. It will cost you 6dB of signal strength. Splitters with amplifiers won't work backwards. Some 'low loss' passive splitters might also not work.

I opened one of those things up once to see what the circuit was. The input came to the centre tap of a transformer consisting of two turns through a ferrite bead. The two outputs came from the ends of this transformer. If you know anything about circuit theory you'll realize that this thing is worse than useless. You'd be better off just wiring the three cables in parallel - a trick that might work in your case.