trubble combining antenna and tv out from 622 on one coalial feed

[wayne Heim]

I have an antenna with a preamp booster on it for over the air hd-channels. I can hook it into the entire look feeding the house just fine and get good (75%+) digital and analog signal quality even on the farthest away tv. I want to take the moduated dish signal (via channel 60) and also feed that to the rest of the house. I was sold a "VHF - UHF combiner" to combine both signals into the same line. When ever I hook the dish output up to the combiner I loose channel 5-1 and 8-1. I unhook the dish feed and everything goes back to normal signal levels of around 80%. When it's hooked up the signal level on these two channels read zero. Funny the annalog versions of these channels work just fine. Any suggestions? Oh the combiner says 5-1100 MHZ and it's passive. Do I need some kind of filter or a different combiner or if it's a problem with the modulator, if I buy a channel 4 modulator to move the signal into the vhf band, would that help? Very confused.

Thanks in advance.

Wayne

 

[topcat0399]

I have an antenna with a preamp booster on it for over the air hd-channels. I can hook it into the entire look feeding the house just fine and get good (75%+) digital and analog signal quality even on the farthest away tv. I want to take the moduated dish signal (via channel 60) and also feed that to the rest of the house. I was sold a "VHF - UHF combiner" to combine both signals into the same line. When ever I hook the dish output up to the combiner I loose channel 5-1 and 8-1. I unhook the dish feed and everything goes back to normal signal levels of around 80%. When it's hooked up the signal level on these two channels read zero. Funny the annalog versions of these channels work just fine. Any suggestions? Oh the combiner says 5-1100 MHZ and it's passive. Do I need some kind of filter or a different combiner or if it's a problem with the modulator, if I buy a channel 4 modulator to move the signal into the vhf band, would that help? Very confused.

Thanks in advance.

Wayne

Try the simplest thing first like using a different channel number for the modulated output from the dish box. mess with it. try channel 22, ch 25, ch 33, etc, and see if that does the trick. otherwise post the details (make/model) of this combiner you are using.

 

[Barry Erick]

Let me guess. The RF channels for 8-1 and the other are UHF and you have that stuck on the VHF side. That would be by the analog CHF channel 8 comes through and the digital does not.

 

[boba]

What OTA channels are active including the digital broadcast channels in your area?

 

[KKlare]

Use a 2-input diplexer/multiplexer and not a UHF-VHF band splitter in reverse. The diplexer will cost a little in signal level but the Dish output is already raised. The diplexer many send a tiny amount of your Dish receiver's signal out of your antenna but unless someone aims their high-gain antenna at yours they will not see anything.

You could get 2 to 4dB less loss with a splitter but as you need UHF for the Dish signal (cable ch 23 up and OTA higher) the antenna would be useful only for VHF and most HD channels are on UHF now although a few may be on VHF. Some UHF digital signals may return to VHF after the transition to keep their identity and coverage, mostly a bad idea, and some digital signals are already on on VHF, especially very bad for low-band VHF 2 to 6.

5-1 does not mean the digital signal is on VHF as digital signals are remapped. For example, our PBS analog 5 has digital 35.1 mapped to 5.1, etc. Before selecting a channel, see what broadcast channels there are. The future OTA limit is 59 or 60 IIRC for broadcast. (OTA UHF channel 37 will be empty as it is saved for radio-astronomy. Do cable system obey that?)
-Ken