DVR install question (dual-tuner)

[bobmckenzie]

Hi all,
Newbie here, so hope i don't get terminology wrong.

I'm moving from dish (old DVR system) to Direct TV and I've got a DVR system coming with dual-tuner capability. I believe i'll need two lines from the dish to the receiver to take advantage of the dual tuner. However, I'm on a slab in a two storey house in atlanta, ga so i believe they will attempt a two storey wall fish.

My question is, instead of running two lines, is it possible to diplex the two signals from the dish onto one coax cable running into the house and then split it again before it goes into the receiver?

I know the splitting is possible - that's how they'll handle multiple TVs/multiple receivers, I was curious about multiplexing two signals on to one cable? that would be a whole lot simpler than running a second line.

TIA for the advice,
Bob

 

[Mike500]

Nope. Dplexors only work with two different frequency bands.

A multiplexor is a device that places more than one frequency spectrum on one line or one signal.

A triplexor places three frequency spectra on one line or one transmitted signal.

A diplexor is a device that places two frequencies in one line.

The so called "combiner" is a diplexor. The sat c lnb has a lower frequency than the sat b lnb.

A multiswitch with only a sat b lnb f1xed to the tone input port will see and translate sat b transponders.

A multiswitch with ony a sat c lnb f1xed to the tone input port will see and translate sat c transponders.

With both the sat b and sat c signals sent to the cable with the combiner (which is electronically a diplexor), the 22 Khz port sees both the sat b and sat c transponders.

Another type of diplexor called a combiner is a common TV VHF/UHF combiner allowing the placement of two separate differing frequency spectra on one cable.

The most common diplexor to us are the ones combining analog cable/broadcast bands with lnb signals on one cable.

A signal stacker technically has a built in diplexor as does a destacker. It also includes frequency conversion equipment. DishPro technology uses diplexors and stacker/destackers.

In all cases, none of these combiners or diplexors translate the signal. That is done by the multiswitch or the conversion sections of the ird, stacker/destacker or that section built in to the tv receiver. Early tv's did not have this ability. There were separate input feeds for both VHF and UHF. If the VHF and UHF signals were "combined" or diplexed at the antenna, a second diplexor called a "separator" was needed at the TV set.


There is also the problem of switching voltage. A high 18 volt signal on the same line will switch the second satellite input to even transponders, when the DVR wis recording on an odd transponder.

 

[bobmckenzie]

Thanks Mike.

So to make sure I understood the crux of the issue: can't use a combiner/diplexor because it would be attempting to add two signals of the same frequency onto one cable - right?

Disappointing, but that's the science of it I guess.

The real problem now is that I've been talking to the install company for 7 days and after several promised but unreturned calls and two no-shows from their installers etc etc, i was just looking for an easier way. I guess I'm still at their mercy. Still no schedule for install. Hopefully they'll get their act together tomorrow.

Bob.

 

[Hogarth]

There are things called stackers / destackers which can help, but they cost several hundred dollars. Running another line will cost a fraction of that.

Search for stacker here, you'll see plenty of threads.

 

[jgtoyota1]

Hello guys! I am new to this site, but have a question along these same lines. I have Directv system with 2 LNB dish. Currently I have a DVR and 3 recievers hooked up from a multiswitch. I want to hook up the 2nd input to the DVR. Any suggestions? Will another multiswitch work, or do I need a 3 LNB dish? If a multiswitch will work, how would you wire it? I have the ability to run the second line to the DVR but how do I hook it to the dish and still have the other 3 reciever work? Any help would be appriciated.

 

[bobmckenzie]

Thanks for the feedback

Thanks Mike and Hogarth. Right now I've got more basic problems like the install company not calling me back when they say they will, not having a competent installer out yet, waiting, waiting and getting more frustrated.

So based on your feedback I'll focus on my more basic issues and pursue the two storey wall-fish to get the second line in place.

Bob

 

[Hogarth]

toyota:

replace your existing multiswitch with one with more ports.