Diplexer added but only OTA sig is a go

[vinnyv07]

Hello...I have a problem here. I have had two lines running one from my OTA Antenna to the receiver and one from the Voom Dish to the receiver. I wanted to combine the 2 sigs and use the other coax for a FTA receiver rather than run yet another coax. So I went up to my roof and connected a coax to the diplexer that combines the two sigs ...and then went inside the house to attach the combiner to the back of the VOOM receiver. Problem is the VOOM sat sig is 0 now and the OTA sig went down a bit but that was to be expected. OTA comes in and VOOM doesn't. I went back to my roof and disconnected the coax from the diplexer that was coming from the OTA Antenna. BOOM...the VOOM sig pops back on. What the heck am I doing wrong here? Which is bad the diplexer or the combiner. When I had the Stealth hooked up before I bought a newer OTA Antenna the combiner worked. But now...I have no sig when using the combiner. I have no preamp...just a straight run from the OTA Ant to the diplexer ...and then the one line into the Voom box in my house. Anyone have a clue what is going on?

 

[Sean Mota]

vinny,

it could be a bad diplexor.

 

[Ilya]

Look at the picture on the diplexer itself (the one on the roof) and make sure you connected it correctly and that you have the right type of diplexer. The diplexer must be able to pass voltage to the LNB.
In addition, if your OTA antenna has a built-in pre-amp, the diplexer must pass voltage to the antenna as well. On the other hand, if the antenna does not have a pre-amp, then the diplexer should not(!) pass voltage to the antenna!
In either case, make sure not to use any power supplies (power-inserters) between two diplexers!

Good luck!

 

[vinnyv07]

Look at the picture on the diplexer itself (the one on the roof) and make sure you connected it correctly and that you have the right type of diplexer. The diplexer must be able to pass voltage to the LNB.
In addition, if your OTA antenna has a built-in pre-amp, the diplexer must pass voltage to the antenna as well. On the other hand, if the antenna does not have a pre-amp, then the diplexer should not(!) pass voltage to the antenna!
In either case, make sure not to use any power supplies (power-inserters) between two diplexers!

Good luck!

Ok went back onto the roof...The diplexer that is up there came with the VOOM install. The Stealth Ant came with my install also. Since the Stealth wasnt cutting it for me , I replaced it with an non powered antenna. So....from what you are saying Ilya is that the diplexer I now need should not pass DC voltage as mine does now. So if they give me another diplexer they should give me one that doesnt pass any voltage...correct?

 

[Ilya]

Correct. Stealth usually comes with a built-in pre-amp. So, most likely you have a diplexer that passes voltage to the antenna. Your new non-amplified antenna might be short-circuiting that voltage, and as a result you are not getting any voltage to the LNB.
Yes, you can ask the installer to replace it for you, or just go to RadioShack and buy a replacement diplexer yourself. It is not that expensive.

 

[vinnyv07]

It says "DC Pass" on the diplexer....so when I disconnect the OTA Ant from the roof it allows the voltage to pass through to the lnb and in turn gets the sig to the Voom receiver. Correct? Why hasn't anyone else had this problem...I guess most people have 2 lines run to the receiver. I wanted to use the other line to set up a FTA receiver. The thought of running yet another coax to my living room frightens me.

 

[shaun-ohio]

i have had the same problem with mine since day one install, i could not use the diplexer either, the only way i could get and still get my local channels is to use an a/b switch and run one coax from the sat and the other coax from the ota antenna, it has been this way for me since my may install, its a real big headache, in order to watch voom you need to use a a/b switch, and when you want to watch the ota channels you need to get up everytime out of your recliner and switch it back and forth, i have had them here from install 3 times and they said as long as that worked,to continue to use it that way, this is a real big convenience for me on needing to use an a/b switch instead of a diplexer, because everytime i switch it to one side and watch the local channels it puts the rec in standby mode and then i lose the program info, try to figure this one out?

 

[Ilya]

It says "DC Pass" on the diplexer....so when I disconnect the OTA Ant from the roof it allows the voltage to pass through to the lnb and in turn gets the sig to the Voom receiver. Correct?

Correct. Basically, by disconnecting the antenna you eliminate the short circuit.
That diplexer passes voltage to both inputs at all times, but the short circuit caused by the antenna, effectively takes voltage away from the LNB...

Why hasn't anyone else had this problem...

When antenna is installed at the same time with the dish, the installer usually knows what type of diplexer to give you. In your case, the installation of the second antenna was done without diplexer present, so the installer didn't replace the diplexer, I guess.

 

[Ilya]

shaun-ohio,
Could you explain how is the A-B switch connected. I am confused...

 

[vinnyv07]

i have had the same problem with mine since day one install, i could not use the diplexer either, the only way i could get and still get my local channels is to use an a/b switch and run one coax from the sat and the other coax from the ota antenna, it has been this way for me since my may install, its a real big headache, in order to watch voom you need to use a a/b switch, and when you want to watch the ota channels you need to get up everytime out of your recliner and switch it back and forth, i have had them here from install 3 times and they said as long as that worked,to continue to use it that way, this is a real big convenience for me on needing to use an a/b switch instead of a diplexer, because everytime i switch it to one side and watch the local channels it puts the rec in standby mode and then i lose the program info, try to figure this one out?

WOW...thats pretty bad. I would have insisted that another coax line be run for the OTA Ant. I dont think anyone could expect you to get up everytime you switch from local OTA to VOOM ch's. Maybe this is your problem also. I called VOOM before and I told them about it....they were supposed to call me back with a date for a visit...but maybe I'll just go to Radio Shack and by a diplexer myself.

 

[shaun-ohio]

they did run a coax in from the ota and it wouldnt pick up anything, that was the only way i could get the local channels was to run a separate coax from the ota, into a a/b switch. an a/b switch is a thing for video where you can hook up 2 individual coax coming into it, it sorta acts like a splitter but its not a splitter, i hope the new dvr voom is coming out is better then my receiver now.

 

[Ilya]

Ok, let me make sure I understand it. You have two cables coming in: one from the antenna, another one from the dish. They are connected to the A/B switch which then connects to the diplexer attached to the back of your STB?
So, what happens if you remove the diplexer and connect each cable to its corresponding input on the back of the STB?
Also, what type of antenna do you have? Do you know if it has a built-in pre-amp?

 

[shaun-ohio]

yes i have 2 coaxes going into my a/b switch then one out to the main input of my voom rec. all i know is there is a square gray box like thing on the main input on the rec. thats where the coax goes into from the a/b switch, i have already tried to connect both coaxes to the appropriate inputs and all it will bring in is the sat part and no local channels, the only way to get the local channels to come in is with a a/b switch hooked up, i have a winegard i think its called looks like it has two wings on it, cant tell you if its pre-amp or not its the one that they installed on may 22nd of this year.

 

[Ilya]

all i know is there is a square gray box like thing on the main input on the rec.

That square gray box is a diplexer. If you remove it (make sure to unlock it by rotating a small black knob) you will see two coax inputs: one for OTA, another one for the dish. See pictures here. This is where you should connect your two cables instead of the A/B switch.

Also, since you seem to have an amplified Winegard antenna, you need to buy the PS-9370 power supply, like this one:


Of course, another option is to replace the A/B switch with a diplexer that passes voltage to the antenna. But since you already have two cables coming in, why bother with diplexers? I would just buy the power supply, if I were you. Call Winegard at 1-800-288-8094 and find a local reseller. Or get it cheap on Ebay.

Good luck!