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Discussion Starter · #1 ·
My apology if this question is somewhat off-topic for this board, but it doesn't fit perfectly anywhere.


I've got a rooftop mounted medium directional antenna w/pre-amp on a rotor, so my local OTA stations come in very nicely, at least when I connect directly to my TV, or to a VCR and then to the TV. However, when I route through the "antenna in" on my Satellite receiver, the reception is noticeably worse, so I don’t connect this way.


I'm switching from Dish Network to direct TV, and just got my Hughes E-86 HD receiver. New dish & service is not installed yet, but last night I connected my antenna signal to the HD receiver just to check out the OTA digital broadcasts.


Just like with my DishNetwork receiver, the OTA analog channels were noticeably worse, maybe even more. This is quite frustrating, since now I have to route the antenna signal through the SAT receiver if I want to see local digital channels, but I don’t want to ruin the reception on the many analog channels I still want to watch. I can probably split the antenna signal and connect one half direct to my TV & the other to the HD receiver, but splitting will probably diminish the quality of the picture anyway.


This doesn't make sense, particularly since routing the signals through VCRs doesn't seem to have the detrimental effects like on both Satellite receivers. I cant imagine the SAT receivers are made such that this is to be expected, so something must be wrong.


The only thing I can guess (a wild guess since I have no technical understanding that suggests this is the cause) is that maybe my SAT being ungrounded has something to do with it? The guys that did the Satellite installation several years ago never bothered to ground the dish or use a ground block where the coax enters my house, and I've always wondered what ill effects this might be producing? My SAT picture has always been quite nice, so you know - if it ain't broken don’t fix it.


I would really appreciate if anyone has any advice here, before I call DishNetwork or Direct TV and pray that I get a technician who knows something.


Thanks.
 

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I take it that your satellite receiver is connected to your TV using the channel 3/4 RF. Did you turn off your satellite receiver when you tried to watch local analog broadcast TV?


Grounding will have absolutely nothing to do with this. The insertion of your broadcast TV loop connection through your satellite receiver should be as miniscule as the loss through your VCR.
 

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Try a splitter. It works for me and my receiver is also built by Hughes but for Toshiba. If you get a drop in quality, a small distribution amp should take care of it. You didn't say what outputs you are using from the receiver. If you run the coax from the receiver to the TV, the receiver is sending a signal out through the coax on channel 3(4). If you have other outputs working as well, this may create a problem.
 

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Discussion Starter · #4 ·
AntAltMike


when it was routed thru the SAT receiver, the both the Satellite signal and antenna signals were connected to their respective "F" connector inputs, and the "F" connector "out to TV" coax from the Receiver was connected to the TV "F" connector input. Turning off the SAT receiver was the only way that the receiver would allow the OTA channels to pass thru to the TV.



greywolf,


when I temporarily connected the new HD receiver last night, I was outputting thru RGB component cables. I had my TV set configured to take the signal from the RGB colorstream inputs, so I believe everything was set up right.


I'm curious why you use the splitter - same problem as I am experiencing? Also, what is a "small distribution amp" ? Is this just a simple "in-line" amp (no power or adjustments, just a device about 2" long with male "F" connectors at each end) ?
 

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A distribution amp is like a powered splitter. It's plugged in to AC and has one RF input and 2 to maybe 8 RF outputs. A good one will have tilt compensation to account for differences in propagation of channel frequencies but even a cheap one will compensate for splitting loss. Try a splitter first. It often does the trick. With the receiver not connected to the TV with RF, all the channels from 2 to 999 act the same. I do nothing to the receiver except pick a channel. The TV is used as a monitor only and I only use its on/off, aspect ratio, and input choices. My receiver and and VCR get the split antenna signals. The TV has no RF input, just component from the DVD and satellite receiver and S-video from the A/V amplifier.
 

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You've never explained why you would leave your Sat/HDTV tuner box on when you desire to view local, analog broadcast programming, Nevertheless, there is often a good reason to leave it on. You may be recording satellite programming for later viewing while watching analog broadcasts live at the same time.


Splitter loss is not the same as the signal loss you experience when your Sat/HDTV receiver is on. Basically, your Sat/HDTV receiver has a relay or equivalent electronic circuitry inside of it that severs the antenna signals path from its input to its output.


The introduction of a splitter will only have visible effects if the result of the additional signal reduction lowers the input signals down to about -5dBmv or less. With any signal level above that, there will be no visible change in picture quality.


Since you are already using a preamp, it is highly unlikely that you would benefit from a distribution amplifier. If you are not well above the noise floor and tuner threshold at this point in your circuit, then the signal developed at your antenna output was probably already too weak to ever produce a good picture.


Tilt compensation is relatively unimportant and usually unnecessary for broadcast television signal distribution within a single home. Tilt compensation can be useful in distribution cable TV signals over a long distance, but with broadcast signals, you have no way of knowing which signals might be dangerously high or low, and even if your wiring has a tilt of a few dB, there is no benefit from arbitrarily reducing your lowband channels (2-6) from, say, 10dBmv down to 5dBmv. Try just the splitter, but if you see graininess in the analog reception, then we'll have to evaluate your reception situation, including likely signal levels of all of your broadcast channels, not just the problem ones.
 

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Discussion Starter · #7 ·
AntAltMike,


Just to clarify, in the past I never did leave on (or attempt to) my SAT Receiver while watching local analog channels. With my older (current set-up) Dish Network receiver, you simply must turn it off to watch the antenna signals if you have connected thru the receiver rather than direct connect to the TV.


With the new HD Receiver, it is designed to be kept powered up for viewing the antenna channels. It recognizes the channels and gives an on screen programming menu for all of the locals (analog & digital), just like for the satellite channels! It's really a great feature, so I definately want to view the OTA channels this way, rather than my current set-up with the antenna connected direct to my TV (where you have to surf to see what is on the antenna channnels).
 

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Does your new receiver have a TV/sat button that will allow it to pass through the antenna input without actually powering that receiver off? That may save you a few seconds in going back to the on screen programming menu.


I've never heard of anything that develops an on-screen program menu for the analog channels. Where is it getting this information from? Is one or more of your local digital signals furnishing it. Is it just the programming information for analog channels from license holders that are also transmitting digitally, or does it include programming information for the independent stations that are only available in analog at present?
 

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Discussion Starter · #9 ·
I have to tell the receiver my zip code. Then the receiver does a "search" for antenna channels (analog & digital) just like programming a TV or VCR with cable TV. DirectTV somehow knows what all the local channels are for a given zip code, and downloads the schedule along with the SAT channel schedule. Pretty cool huh?
 
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