Tivo RF ghosting - Can anyone help?

[pipkato]

My Tivo RF output has been ghosting badly since I bought it secondhand last year. I ignored it until now because the Scart output was fine and I only used the RF output to feed a small TV in another room.

However I've now swapped that small TV for a 32" LCD and the ghosting is really a big problem. Originally I thought it might be an issue that could be resolved by setting a different RF channel (I'm currently using 60). However I've now tried other channels and Channel 60 is as good as I can get. Many of the others show obvious cross-channel? wavy line interference.

The ghosting is in the form of repeated blurry images of defined shapes to the right of the correct image. They seem to continue right across the screen.

I wondered if anyone knows a likely cause and if possible a fix for this problem? I'm viewing it via a domestic RF distribution amplifier and the cable length from the amplifier to the new LCD is about 45 feet. The RF amp is fine as connecting a TV directly to the Tivo RF out shows the same ghosting.

Is this a known problem with the Tivo RF out? Is there any fix or a way to replace the RF module?

Thanks.

[RichardJH]

It sounds like cross channel interference try this http://www.garysargent.co.uk/tivo/TabooChannels.htm
OR
http://www.kat5.tv/taboo_guide.html

[pipkato]

thanks RichardJH.

Very useful and interesting links, but I don't think it's cross-channel interference, at least not the kind I've seen over the years, and the type I described with the herringbone or wavy line patterns.

What I'm getting is a fuzzy version of the image (particularly the high-contrast sections) spreading across to the right of the screen. As I said, I did try some alternative channels and many of those gave me what looks to me like cross-channel interference, and eventually went back to Channel 60, which have no herringbone patterns but did have the 'ghosting' effect.

Anyway, I'll have a go again using the links you suggested and see if I can find any channel that works.

[Sherminator]

Have you tried:

High Pass TV RF filter, (http://www.maplin.co.uk/module.aspx?ModuleNo=29605&doy=1m12)

or coiling the RF cable around a Ferrite Ring (http://www.maplin.co.uk/module.aspx?ModuleNo=29788&doy=1m12)?

[d33mb33]

I asked the same question a couple of years ago and neraly everyone replied and said that they see the problem as well. So it looks like it's interference or cheap components within the Tivo itself.

To get around this, I've taken SCART from Tivo -> VCR and use the VCR RF output to feed the other rooms. No ghosting at all.

[Automan]

From what I recall when I tried to use the internal tuner/modulator in Tivo several years ago that it yielded very poor results :(

Automan.

[guydewdney]

try an RF modulator

http://cpc.farnell.com/jsp/search/results.jsp?N=411+500001+1000366&Ntk=gensearch_003&Ntt=rf+modulator&Ntx=&isGoback=false

?

[pipkato]

Thanks very much for all that sound advice.

I had used the RF modulator of my Mitsubishi VCR in exactly the same way and the picture was fine. So maybe the Tivo RF output is poor, especially across 40+ feet. I don't know if I can run a composite video feed from the Scart across the same distance without issues, but that, or the separate modulator seem to be the way to go.

And thanks Sherminator for the tips about filters. Should be worth a try, although I suspect my problems are not external interference, but a modulator issue.

[RichardJH]

Have you tried feeding the RF output to a TV without any aerial feed into the Tivo just the scart stb input that will clear up whether it is the Tivo tuner/modulator or cross channel interference

[pipkato]

Thanks RichardJH.

I don't use aerial input to my Tivo at the moment. I'm in Ireland and we have no way to use the local off air channels combined with a satellite STB. I hope to set something up soon using a DTT box and feed our local DTT trials by RF into the Tivo.

Anyway, I'm not using the aerial input at present.

[aleks]

I'm afraid that the TiVo modulator just isn't that good. Mind you the ghosting could be due to an impedance mismatch or damage to the cable between the TiVo and the TV. Have you tried a different and short lead from TiVo to TV? That would prove whether it's the TiVo or the cable.

Ideally you should use one with decent cable - although they are hard to come by and a bit expensive just for a test unless you can make one for yourself.

40 feet is a long run for domestic aerial cable. Have you tried feeding the TiVo into a signal booster?