Another Diplexer Question

[Human123]

I have been reading threads about diplexing and still don't know if I have my answer. I have an existing Zinwell 6X8 switch which has a oval dish (3 LNB) and a round dish (72.5) into the flexport.

I want to know if I can use my existing Terk (BDS-P1) diplexers to add an OTA signal from an existing Terk-TV50 attic antenna? The Zinwell has 4 wires on the output to 2 DTivos (Series 2) I want to know if I can place a diplexer on 2 of the 4 output cables (1 from each TV pair) to add in the OTA signal and then diplex from the proper cable at the TV locations for OTA to the TV's? Everything I read about these diplexers says to use on a single LNB dish, but my hopes are it will work on the output side of the multiswitch.

I also have some of the Terk DC Block devices (TDCB) that I want to know if they should be installed where I diplex out to the TV's (antenna side)? I have read the Terk TV-50 antenna gets power from the sat receivers so again another question of whether doing this to 2 seperate Sat receivers will cause issues. (I could live with only one working)

I have just about all of the parts I am talking about and would just try, but don't want to damage any equipment.
I think being in the Boise, ID market the diplexing will be a moot issue sometime in the future as our locals are moving to MPEG4 and I will get a new dish that I read won't support diplexing. However, in the meantime I could be enjoying some HDTV OTA if my existing materials will work.

Any help would be appreciated.
TIA

[cramer]

The fact that your multiswitch doesn't have a "TV" port on it should be a key indicator. The answer is almost certainly no if that's the WB68 ("wideband") zinwell multiswitch. You might be able to get away with it in a non-mpeg4 setup, but not without a multiswitch capable of stacking the antenna/cable in the first place.

[Human123]

The fact that your multiswitch doesn't have a "TV" port on it should be a key indicator. The answer is almost certainly no if that's the WB68 ("wideband") zinwell multiswitch. You might be able to get away with it in a non-mpeg4 setup, but not without a multiswitch capable of stacking the antenna/cable in the first place.

Hi, thanks for your response. The switch is a Zinwell "SAM-6802" and as you know, it doesn't have a TV input.

I thought the Terk diplexer could do the "stacking", but I only see that in my searching as a "one wire solution" and they have the outside diplexer fed directly from a single LNB (not switch output). My hopes were that I could add an outside diplexer to the outputs of the Zinwell switch (times 2) for my DTivo setups (for OTA Tuner)
I am concerned to just try this because the outputs of the Zinwell are mixed of all the LNB inputs (including 72.5 on one of the flexports) and I can't find anywhere showing this as a valid hookup.
I am also concerned about trying it with two different multiswitch outputs wondering if the two DTivos will put different voltage sources back to the Terk TV50 attic antenna. If so, I could be happy only doing this to one TV. I still don't quite understand how the Terk antenna gets power from the satellite receivers and whether I should use DC blocks anywhere in the wiring.
Thanks

[JimSpence]

The way to do this is to split the OTA signal and diplex them onto the appropriate cables from the multiswitch outputs to the TVs needing OTA. Then use diplexers on those lines to separate at the TVs. Now, if you upgrade to MPEG4, then this changes.

[Human123]

The way to do this is to split the OTA signal and diplex them onto the appropriate cables from the multiswitch outputs to the TVs needing OTA. Then use diplexers on those lines to separate at the TVs. Now, if you upgrade to MPEG4, then this changes.


Excellent! So if I understand what you are saying there is not any issues with diplexing from the outputs of my switch and then diplexing back on the correct cable at my DTivo locations?

Are you familiar with the Terk TV-TV50 antenna? It states that it utilizes power from the satellite receiver to bump up the antenna signal through the diplexer. If I was to diplex one line of each of my DTivo's, do you see any power conflict at the antenna? Also, Terk sends out these TDCB DC Blocks with the diplexers. Do I need to install these on the RF inside diplexer? Or not use them at all?

Thanks!!!

[JimSpence]

Right! Diplex after the switch.

I'm not familiar with the Terk antennas. Typically, the diplexer only passes DC on the sat side to allow the receiver to send the DC control voltage. I can only guess that since the Terk utilizes the receiver voltage then the diplexer to use would need to pass power on both legs. What the DC blockers are for is someone elses guess to answer. Unless they are needed at the TV end.

[Human123]

Right! Diplex after the switch.

I'm not familiar with the Terk antennas. Typically, the diplexer only passes DC on the sat side to allow the receiver to send the DC control voltage. I can only guess that since the Terk utilizes the receiver voltage then the diplexer to use would need to pass power on both legs. What the DC blockers are for is someone elses guess to answer. Unless they are needed at the TV end.

Thanks Again!

The Terks do pass DC on both sides. I believe the blocks are only intended to be used on the antenna side, but it is not clear to me when to use and when not to. I will give it a try first with a block at the TV end only. If I don't get signal I will remove it. I just don't want to damage a tuner or anything since the Terks do pass DC.

[JimSpence]

I would run separate coax from the OTA splitter to the TVs needing it. This way you won't have a problem with damaging anything.