Just curious, about how much loss would you have if you used a diplexer to combine OTA and a Dish 1000 feed? Cable run of approx. 75 feet. Thanks!
How much loss with a diplexer?
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2.0 dBmV for the satellite leg and 1.0 dBmV for the VHF/UHF leg per diplexer. Plus whatever loss in the 75 ft. Average is about 9.0 dBmv for 100 ft.
iafirebuff said:
Not really. If you split the OTA signal then you may have an issue because every splitter is 3.5 dBmV loss. Other than that, I'm using diplexers for my 211 receiver and Cable Internet. For the 211 receiver the run is almost 200 ft. and for the Cable Internet the run is about 100 ft. I get signal of +3.3 dBmV in my cable modem and have no problems with the satellite signal.
I found my numbers. For a Dish Network receiver to work you need -60 dBmV. LNBs output average of -38 dBmV. So let's say you start with -38 dB from the LNB, add about -7 dB for the 75 ft., plus -4 dB for the diplexers and your total is only -49 dB. You're fine with the satellite signal.
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Thanks! Here is why I asked: My upgrade was today, I spent 5 hours last night inthe dark re wiring my house and all tvs with Dish runs, and OTA, color coding all cables, taking down old Dish 500, so all the tech would have to do is place the Dish 1000 on the mast, hook it up to the cable (with diplexer) and place the receiver in the house, and plug it in. Should be real short, right? WRONG! It took him 4.5 hours! My wife called me at work and said the guy was clueless. I had everything marked, real simple job. She put him on the phone...he said diplexers will degrade my signal, etc, so I did not argue, I just said ok do what is easiest for you, knowing I can reverse and redo it the way I wanted it. So, long story short, he moved where the dish was mounted, ran a new line without a diplexer, and after he left, I cut his line, re did it into my diplexed line and my signal went up 10-15 points on all 3 satellites! I will make another thread on this install 
OK, here's a question for u diplexer afficiandos........ I have a Dish Network DVR and an Insight Cable Motorola DCT6400 connected to an Hitachi 42HDF52 TV.
The single cable running to my bedroom has a RCA D920 diplexer at each end with the feed from the Dish LNB connected to the 'Sat' input on the diplexer and the cable feed is in the 'Ant' input. Now, my problem is, I get all of my Dish channels and get all but a few of the HD cable channels. I'm wondering if the RCA diplexer is restricted in frequency and if there is a better diplexer out there that will allow all the HD channels to come in?
The single cable running to my bedroom has a RCA D920 diplexer at each end with the feed from the Dish LNB connected to the 'Sat' input on the diplexer and the cable feed is in the 'Ant' input. Now, my problem is, I get all of my Dish channels and get all but a few of the HD cable channels. I'm wondering if the RCA diplexer is restricted in frequency and if there is a better diplexer out there that will allow all the HD channels to come in?
The RCA D920 diplexer goes down to 40 Mhz, other diplexers go down all they way to 5 Mhz. Having said that, I don't believe any of the HD cable channels are in the frequencies below 40 Mhz. You could try the Holland diplexers that go down to 5 Mhz. It's possible that the Cable box uses frequencies for return path below 40 Mhz.
What happens if you connect the cable directly to the Motorola DCT6400? Do you get all the HD channels.
What happens if you connect the cable directly to the Motorola DCT6400? Do you get all the HD channels.
I don't know of any cable system with downstream content at frequencies less than OTA TV CH2 which is 54 MHz on the low end. (There are the "subchannels" - 7 to 49MHz. Does anyone use them for downstream content?) In most domestic systems, the "split" is 42/54 MHz, meaning those are the rolloff (3dB?) frequencies for the low pass and high pass diplexers in the CATV trunks and bridgers. The upstream content below 42MHz is usually just the internet traffic from the subscribers.
Then you should try the Holland diplexers that go all the way down to 5Mhz.
Bhelms,
I'm with you too. I've never heard of a cable system that will go below 40 Mhz, except for the cable broadband upstream or return path. But something is odd with his cable system because it works when he doesn't use diplexers.
Bhelms,
I'm with you too. I've never heard of a cable system that will go below 40 Mhz, except for the cable broadband upstream or return path. But something is odd with his cable system because it works when he doesn't use diplexers.
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I wonder if the 920 has an upper end roll-off on the antenna side that is too low in freq. for the HD signals NewAlbanyDish is missing? I looked briefly for some tech specs. on that unit but couldn't find anything other than dimensions. Note that some cable systems are now upgrading RF equipment to 1GHz capablility. It's easy to imagine some older passive components that won't operate that high. Maybe another brand of diplexer (Holland, as RA suggested) would work better? I found that RCA model on line with a base price as low as $2.64 so it's easy to imagine that it's not the best available.
EDIT: The Sonora HRD2 is rated 15-806MHz on the antenna side. Maybe that would work better? http://www.swidendist.com/detail.aspx?ID=390
EDIT: The Sonora HRD2 is rated 15-806MHz on the antenna side. Maybe that would work better? http://www.swidendist.com/detail.aspx?ID=390
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The Holland diplexer is rated:
5-890 Mhz on the VHF/UHF/CATV Port
950-2150 Mhz for the Satellite port.
Neither diplexer goes all the way to 1 Ghz.
5-890 Mhz on the VHF/UHF/CATV Port
950-2150 Mhz for the Satellite port.
Neither diplexer goes all the way to 1 Ghz.
Sorry - overlapped your postRandallA said:
I guess the 1GHz antenna-side version would be impossible as long as there is a need for the sat. side to be rated down to 950MHz. Looks like the Holland is the best choice...
