Sign in with
Sign up | Sign in
Your question

Combining outputs from two TiVos

Last response: in Home Theatre Legacy
Share
Anonymous
April 1, 2005 1:17:32 AM

Archived from groups: alt.video.ptv.tivo (More info?)

If I set one TiVo to output through RF Channel 3, and the other to output
through RF channel 4, is there any way to mix the two modulated outputs into
a single coax, so that I can choose which TiVo to watch via the TV's channel
selection? (Sort of the reverse of a splitter -- an inexpensive RF mixer).

- David
Anonymous
April 1, 2005 6:36:07 AM

Archived from groups: alt.video.ptv.tivo (More info?)

Once upon a time, David D. <daviddiamond.remove-if-not-spam@comcast.net> said:
>If I set one TiVo to output through RF Channel 3, and the other to output
>through RF channel 4, is there any way to mix the two modulated outputs into
>a single coax, so that I can choose which TiVo to watch via the TV's channel
>selection? (Sort of the reverse of a splitter -- an inexpensive RF mixer).

It is called a "combiner", and you can usually find them at Radio Shack
for not too much more than a standard splitter.

However, many RF modulators (especially those built-in to things like
TiVos) don't put out "clean" signals. They'll bleed over into near-by
channels, so you usually can't combine channels 3 and 4. You can try it
(there's not much to lose), but you'll probably need to get an RF
modulator that can put out to a different channel. I've used a UHF
modulator (on channel 14) combined with a channel 3 output without
interference.
--
Chris Adams <cmadams@hiwaay.net>
Systems and Network Administrator - HiWAAY Internet Services
I don't speak for anybody but myself - that's enough trouble.
Anonymous
April 1, 2005 6:36:08 AM

Archived from groups: alt.video.ptv.tivo (More info?)

Thanks, Chris.

- David

"Chris Adams" <cmadams@hiwaay.net> wrote in message
news:114pcsnidapn493@corp.supernews.com...
>
> It is called a "combiner", and you can usually find them at Radio Shack
> for not too much more than a standard splitter.
> --
> Chris Adams <cmadams@hiwaay.net>
> Systems and Network Administrator - HiWAAY Internet Services
Related resources
Anonymous
April 1, 2005 8:34:13 AM

Archived from groups: alt.video.ptv.tivo (More info?)

In article <hPOdnRPp35-9MtHfRVn-sQ@comcast.com>, daviddiamond.remove-if-
not-spam@comcast.net says...
> If I set one TiVo to output through RF Channel 3, and the other to output
> through RF channel 4, is there any way to mix the two modulated outputs into
> a single coax, so that I can choose which TiVo to watch via the TV's channel
> selection? (Sort of the reverse of a splitter -- an inexpensive RF mixer).
>
> - David
>
>
>
>


I don't think that would work since they'd both be on at the same time.
What would work is to plug one tivo into the rca jacks and one in the
coax. Then you could easily switch back and forth.
Anonymous
April 1, 2005 1:54:34 PM

Archived from groups: alt.video.ptv.tivo (More info?)

"David D." <daviddiamond.remove-if-not-spam@comcast.net> wrote in message
news:hPOdnRPp35-9MtHfRVn-sQ@comcast.com...
> If I set one TiVo to output through RF Channel 3, and the other to output
> through RF channel 4, is there any way to mix the two modulated outputs
into
> a single coax, so that I can choose which TiVo to watch via the TV's
channel
> selection? (Sort of the reverse of a splitter -- an inexpensive RF
mixer).

The quality of the RF modulators in most devices is not good enough to make
it work reliably. They just overlap too much to make either of them
viewable.

Your alternatives are to watch one on RF and the other s-video (or
composite) or to add a second RF modulator. I've done the latter. I run
other devices on their own RF channels via a Channel Plus RF modulator.
That way every TV in the house can see the Tivo on ch.3 and the other
devices on their own channels. Works great.

Bear in mind, however, that I'm not running any external RF channels into
the system (no outside analog cable or OTA signals). If you need to 'mix
in' external RF channels they you'd need to get into adding various notch
filters to allow your internal channels to run instead of the external ones.
Anonymous
April 2, 2005 12:20:33 AM

Archived from groups: alt.video.ptv.tivo (More info?)

The problem is that my TV inputs are maxed out. Primary RF for cable in.
Aux RF for TiVo in. One analog input for DVD. The other analog input for
VHS. Nothing is left.

The VCR inputs are also maxed out. RF from cable. Analog 1 for TiVo
archiving. Analog 2 is a front panel port, for cameras & video, and would
be unsightly to hook up permanently to a TiVo (also, I might get
degredation from cascading).

I hate the thought of using manual switches.

- David



"wkearney99" <wkearney99@hotmail.com> wrote in message
news:zpmdnenrHJ9j_dDfRVn-rg@speakeasy.net...
> "David D." <daviddiamond.remove-if-not-spam@comcast.net> wrote in message
> news:hPOdnRPp35-9MtHfRVn-sQ@comcast.com...
> > If I set one TiVo to output through RF Channel 3, and the other to
output
> > through RF channel 4, is there any way to mix the two modulated outputs
> into
> > a single coax, so that I can choose which TiVo to watch via the TV's
> channel
> > selection? (Sort of the reverse of a splitter -- an inexpensive RF
> mixer).
>
> The quality of the RF modulators in most devices is not good enough to
make
> it work reliably. They just overlap too much to make either of them
> viewable.
>
> Your alternatives are to watch one on RF and the other s-video (or
> composite) or to add a second RF modulator. I've done the latter. I run
> other devices on their own RF channels via a Channel Plus RF modulator.
> That way every TV in the house can see the Tivo on ch.3 and the other
> devices on their own channels. Works great.
>
> Bear in mind, however, that I'm not running any external RF channels into
> the system (no outside analog cable or OTA signals). If you need to 'mix
> in' external RF channels they you'd need to get into adding various notch
> filters to allow your internal channels to run instead of the external
ones.
>
Anonymous
April 2, 2005 7:56:03 AM

Archived from groups: alt.video.ptv.tivo (More info?)

In message <ZaGdnV0CmKfZbtDfRVn-pw@comcast.com> - "David D."
<daviddiamond.remove-if-not-spam@comcast.net>Fri, 1 Apr 2005 20:20:33 -0500
writes:
:>
:>The problem is that my TV inputs are maxed out. Primary RF for cable in.
:>Aux RF for TiVo in. One analog input for DVD. The other analog input for
:>VHS. Nothing is left.
:>
:>The VCR inputs are also maxed out. RF from cable. Analog 1 for TiVo
:>archiving. Analog 2 is a front panel port, for cameras & video, and would
:>be unsightly to hook up permanently to a TiVo (also, I might get
:>degredation from cascading).
:>
:>I hate the thought of using manual switches.
:>
:>- David


Several years ago I bought a Video Source Selector, RCA VH920. It has 6 inputs
that can be either composite (RCA cables) or S-video. It doesn't have a
remote, but can be programmed to respond to signals from any remote.

It was around $100.
Anonymous
April 2, 2005 12:49:57 PM

Archived from groups: alt.video.ptv.tivo (More info?)

Thanks, Keith.

I will tuck that option away for consideration. For the moment, I don't
want to spend that much on a switch. But it is good to know that the option
is out there.

- David


"Keith E. Moe" <keith@laidbacksoftware.com> wrote in message
news:nJo3e.6019$FN4.5970@newssvr21.news.prodigy.com...
> In message <ZaGdnV0CmKfZbtDfRVn-pw@comcast.com> - "David D."
> <daviddiamond.remove-if-not-spam@comcast.net>Fri, 1 Apr 2005
20:20:33 -0500
> writes:
> :>
> :>The problem is that my TV inputs are maxed out. Primary RF for cable
in.
> :>Aux RF for TiVo in. One analog input for DVD. The other analog input
for
> :>VHS. Nothing is left.
> :>
> :>The VCR inputs are also maxed out. RF from cable. Analog 1 for TiVo
> :>archiving. Analog 2 is a front panel port, for cameras & video, and
would
> :>be unsightly to hook up permanently to a TiVo (also, I might get
> :>degredation from cascading).
> :>
> :>I hate the thought of using manual switches.
> :>
> :>- David
>
>
> Several years ago I bought a Video Source Selector, RCA VH920. It has 6
inputs
> that can be either composite (RCA cables) or S-video. It doesn't have a
> remote, but can be programmed to respond to signals from any remote.
>
> It was around $100.
>
>
>
Anonymous
April 2, 2005 1:37:17 PM

Archived from groups: alt.video.ptv.tivo (More info?)

> The problem is that my TV inputs are maxed out. Primary RF for cable in.
> Aux RF for TiVo in. One analog input for DVD. The other analog input
for
> VHS. Nothing is left.
>
> The VCR inputs are also maxed out. RF from cable. Analog 1 for TiVo
> archiving. Analog 2 is a front panel port, for cameras & video, and would
> be unsightly to hook up permanently to a TiVo (also, I might get
> degredation from cascading).
>
> I hate the thought of using manual switches.

Then get an IR controllable video switch. SIMA makes a nice one, I've had
one for years.

Push the video (or, ideally, s-video) from each source into the switch.
Then feed the switched s-video to your main TV. For anything else in the
house you could split the video to an RF modulator and let them see the
signal on channel 3.
Anonymous
April 3, 2005 1:19:16 AM

Archived from groups: alt.video.ptv.tivo (More info?)

David D. wrote:
> If I set one TiVo to output through RF Channel 3, and the other to output
> through RF channel 4, is there any way to mix the two modulated outputs into
> a single coax, so that I can choose which TiVo to watch via the TV's channel
> selection? (Sort of the reverse of a splitter -- an inexpensive RF mixer).

The simple and cheap RF mixer is to use a splitter in reverse.
(Using a splitter this in this fashion is the standard way of combining
signals from a UHF antenna and a VHF antenna onto a single coax.)

If both devices output good clean signals on their RF outputs, then
yes, you can mix channel 3 with channel 4. I don't know how good
TiVo is in no spilling over into adjacent channels.
-Joe
Anonymous
April 12, 2005 8:10:20 PM

Archived from groups: alt.video.ptv.tivo (More info?)

Thanks, Joe.

It's worth a try.

"Joe Smith" <joe@inwap.com> wrote in message
news:l-SdnUOcR8BK4dLfRVn-vA@comcast.com...
> David D. wrote:
> > If I set one TiVo to output through RF Channel 3, and the other to
output
> > through RF channel 4, is there any way to mix the two modulated outputs
into
> > a single coax, so that I can choose which TiVo to watch via the TV's
channel
> > selection? (Sort of the reverse of a splitter -- an inexpensive RF
mixer).
>
> The simple and cheap RF mixer is to use a splitter in reverse.
> (Using a splitter this in this fashion is the standard way of combining
> signals from a UHF antenna and a VHF antenna onto a single coax.)
>
> If both devices output good clean signals on their RF outputs, then
> yes, you can mix channel 3 with channel 4. I don't know how good
> TiVo is in no spilling over into adjacent channels.
> -Joe
Anonymous
April 19, 2005 1:45:43 PM

Archived from groups: alt.video.ptv.tivo (More info?)

Channels 3 and 4 do not have adequate separation to work cleanly. What you
need is a "modulator" like the Netmedia MM-73. It takes signals from one or
more inputs (like TiVo's A/V output) and modulates them onto any channel you
want, preferably one not occupied by another device. The channels need to be
separated by one, so you can use channels 24 and 26, but should not try to
use 24 and 25.

User manual for the Netmedia devices:

www.smarthome.com/manuals/7762.pdf

Also remember that the modulator in TiVo is low gain, so it won't power many
TVs. It'll generally power one. Splitting the signal causes a loss that can
be as high as 70% of the original signal depending on the number of ways you
split the signal.


"David D." <daviddiamond.remove-if-not-spam@comcast.net> wrote in message
news:k76dnVetF4GZtsHfRVn-pw@comcast.com...
> Thanks, Joe.
>
> It's worth a try.
>
> "Joe Smith" <joe@inwap.com> wrote in message
> news:l-SdnUOcR8BK4dLfRVn-vA@comcast.com...
>> David D. wrote:
>> > If I set one TiVo to output through RF Channel 3, and the other to
> output
>> > through RF channel 4, is there any way to mix the two modulated outputs
> into
>> > a single coax, so that I can choose which TiVo to watch via the TV's
> channel
>> > selection? (Sort of the reverse of a splitter -- an inexpensive RF
> mixer).
>>
>> The simple and cheap RF mixer is to use a splitter in reverse.
>> (Using a splitter this in this fashion is the standard way of combining
>> signals from a UHF antenna and a VHF antenna onto a single coax.)
>>
>> If both devices output good clean signals on their RF outputs, then
>> yes, you can mix channel 3 with channel 4. I don't know how good
>> TiVo is in no spilling over into adjacent channels.
>> -Joe
>
>
!