Blocking VHF in favor of UHF

Reception, channel detection, network issues, CableCARD setup, etc.
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sporterco
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Blocking VHF in favor of UHF

Post by sporterco »

Is there a way to block a VHF channel when there is also a UHF channel available for the same broadcast station on the Duo?

I live on the fringe of reception (some pixalation) for channel 4.1 VHF (69Mhz) but have been able to get perfect reception on channel 4.1 UHF (527mhz) in the past. When the system is scanning it seems to lock on the VHF channel and ignores the UHF channel. Can I block the VHF channel when scanning which would effectively force the system to recognize the UHF channel instead?

Thanks!

signcarver
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Re: Blocking VHF in favor of UHF

Post by signcarver »

When it comes to the scan (and software reliant on the scan) it is not if same virtual channel number... if different you can disable one.

Channels get added first by resolution if the same it drops down to signal quality. In most instances it should be fairly easy to reduce quality of such a low vhf channel (assuming it is where you say it is) but it may have a higher resolution.

NedS
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Re: Blocking VHF in favor of UHF

Post by NedS »

In other words, in the official HDHomeRun app, when both are the same virtual channel then there is no way to manually select the frequency. If using a third party application, then it might be possible (under the hood, the HDHomeRun will happily tune based on virtual channel number or frequency).

ebo
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Re: Blocking VHF in favor of UHF

Post by ebo »

If there are no other VHF channels you want to receive you could switch to a UHF-only antenna and/or add a UHF/VHF splitter/joiner (a.k.a. UVSJ) to your antenna line as a splitter, using only the UHF output with the VHF out terminated.

Another possibility is to temporarily install an attenuator (a splitter or 2 or more in series will do) until 4 isn't recognized but your other channels are, then do a rescan. If that lists all the channels you want but not 4, then remove the terminator.

527 MHz is channel 23. On RabbitEars I looked up all locations for channel 4 in the US. The only one I found with the same broadcast on 23 was KVOA in Tucson. So if you're in the US I'm guessing that's where you are. 4 is the only low VHF channel in the area but KGUN is on 9 (and 27) and KOLD is on 13 (and 32). 4 and 13 are on Tower Peak on the west side of Tucson, and 27 is on the nearby Tumamoc Hill. They're all repeaters for the broadcasts on Mt. Bigelow on the NE side. So you don't need 13 but you probably do need 9.

signcarver
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Re: Blocking VHF in favor of UHF

Post by signcarver »

There are a couple of lte filters out there that also block everything under 80Mhz that might help.

sporterco
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Re: Blocking VHF in favor of UHF

Post by sporterco »

Thank you all for your input!

Ebo hit on the problem (and I would like to apologize for not being more clear in my request for assistance). I live north of Tucson and have been receiving OTA broadcasts from Mt. Bigelow. I have been receiving all channels on UHF frequencies with the exception of KGUN 9 (vhf for me) but then KVOA 4 got in the mix somehow.

I'm thinking I will try to filter the low vhf signal from the antenna per Signcarver's suggestion. That should block KVOA 4 (vhf) but still allow me to recieve KGUN 9 (vhf).

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