# 942 and Digital tuner,(ugh)



## Jeff McClellan (Apr 22, 2002)

Well I like everything about this receiver except one thing, the digital tuner. I have a Sony kdf-42we655 and a Channel Master 4228 with a pre-amp and rotor mounted on the house. Going through the set I get all my local digital stations around 95 or higher. I can even pull in the digital from Spartanburg SC, and Greensboro NC. But going through the 942 everything drops by 10 percent. It even has issues holding stations at around 80 percent. I have a PBS 23 miles from here that the Sony give me a 91 percent on, and the 942 a 78 percent. This stinks. At this point we are using the Sony for our ota. I dont think this is a problem that is fixable. I really hate this.


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## Mark Lamutt (Mar 24, 2002)

Jeff, you're not comparing apples to apples. There isn't a single signal strength indicator that measures exactly the same thing on exactly the same scale across manufacturers. Meaning, there's no correlation between your Sony television's scale and the 942 scale.

My 942 locals start breaking up below 62. If you're breaking up at 80, there's something else going on somewhere.


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## Jeff McClellan (Apr 22, 2002)

All I know is on channels that showing a stenght of less than 90, with the 942 I get lots of drop outs and pixing. The Sony holds strong. Mark, I dont know if it is software or what, but I have done alot of testing this weekend with it. The tuner is just not as strong. The proof is the distant citys I can pull in with the Sony at around 55 percent and the 942 shows 30 with no picture.


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## Mike Johnson (Jan 16, 2005)

Jeff,
How do you split your antenna to feed your TV and 942 at the same time? What kind of splitter? How many ports? It is amplified?

I also use a preamp, but I had to do away with my 4-port amplified splitter it was using (at least for the digital tuners.) I now use a passive splitter and all is well. 

My 942 tunes in locals with signals as low as 56 without trouble. If you are having trouble with signals in the 80s & 90s, I would suspect a multipath problem, or even just too much signal.

Also, the Sony TVs do appear to have better equalizers than the Dish tuners which means they handle multipath better.


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## Jeff McClellan (Apr 22, 2002)

Mike, the cm 4228 is a very directional antenna. You literally have to aim within 10 degrees of the tower to get it. I even climbed up on the roof and reinstalled my Winegard Ghostkiller and got the same results. As for the splitter. I disconnected it and first piped it directly into the Sony, the the 942. Same results everytime. Mid level to weaker stations will drop quicker with the 942 before the Sony.

Mark, I have also found that any digital station here above .1 doesnt get any guide info, it just says digital station.


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## S.C. Am (Jul 27, 2004)

Your results are rather typical. I have heard of the same scenario with someone who has the Samsung T151 and a 942 - same results.


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## Jeff McClellan (Apr 22, 2002)

My concern is this something that can be addressed with a software update, or, it it hardware related and we will just have to live with it.


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## dougmcbride (Apr 17, 2005)

Mike - I was just getting ready to post a question with regard to using an OTA antenna with a preamp as I'm going to help a friend put in a CM 4228 with a CM 777 preamp. Can you or others help me here?

There will be a 942 and a 811 in the house (new install yet to be performed so there are no existing LNBFs or multiswitches in the mix yet). 

* Would we use the power supply with the CM 777 to power the preamp, or does the 942 or 811 provide power? 

* Since there is only a single coax running to the locations where the 942 and 811 are, we were assuming a DPP44 multiswitch would be needed and that a separator would be used at the 942. Is this correct? Does a DPP Twin LNBF come into play here at all or does the DPP44 provide the desired functionality?

* Where in the line would the preamp power supply go if the receivers do not provide power? Would it be between the DPP44 and the separator if on the 942 leg? Or would it be better to put the power supply on the 811 leg? 

* If on the 942 leg, does the diplexer sit between the DPP44 and the separator or between the separator and the 942?

Thanks in advance for any info you can provide. This is all new to me but I'm interested in learning.

Doug


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## Mark Lamutt (Mar 24, 2002)

Doug, I'm not sure you can use a diplexor in line with a DishPro separator. You may be able to, but I've not come across anyone doing it.


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## Mike Johnson (Jan 16, 2005)

Well, it looks like I'm having some issues with the 942 OTA tuner as well. I've been trying to watch my NBC affiliate tonight (KTIV-DT 41 Sioux City) and the signal is constantly pixelating. Signal is 89. My 811 and Sony TV are receiving the signal fine.

Jeff may be on to something, here. If I deliberately mis-point my antenna, I can get the signal to come in without breaking up. I'm also using a Channel Master pre-amp and antenna. Could the 942 just be more sensitive to multipath?


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## Mike Johnson (Jan 16, 2005)

dougmcbride said:


> Mike - I was just getting ready to post a question with regard to using an OTA antenna with a preamp as I'm going to help a friend put in a CM 4228 with a CM 777 preamp. Can you or others help me here?


Doug-I haven't been a big fan of using diplexers. For me, I've always just run another piece of cable because cable is cheap. I would doubt that you can run antenna preamp power through a diplexer.

Anyone else care to comment?


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## Mark Lamutt (Mar 24, 2002)

I'm pretty sure that the 942 OTA tuner is more susceptible to multipath than other tuners. But, I'm also convinced that it's something that can be tuned in software.


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## dougmcbride (Apr 17, 2005)

mike_johnson said:


> Doug-I haven't been a big fan of using diplexers. For me, I've always just run another piece of cable because cable is cheap. I would doubt that you can run antenna preamp power through a diplexer.
> 
> Anyone else care to comment?


Mike - thanks and I agree on the separate cable (which is what I do at my place). In my friend's case, it would require fishing quite a bit of cable through the walls and I was trying to keep it simple by using the existing runs. We'll keep plugging and see if other's have had experience with this type of setup. Worst case, we'll have to go fishing... 

Doug


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## Rob Glasser (Feb 22, 2005)

You can add me to the list of 942 users with OTA tuning/multipath problems

My FOX affliate is brodcasting from about a 45 degree angle from the rest of my locals. I am using a CM4221 which has a pretty wide reception path and it was great with the 921, but not with the 942. I can see that the problem doesn't appear to be strength per se but rather stability. I'm guessing because of some multipath issues my signal strength bounces between about 83 - 91, with an occasionaly dip as low as 78. Only this station has this much range in the signal strength and only this station has audio lose and video pixelization. I have other stations that are solid at say 88 - 89 and they don't have issues. I am going to try tweaking my antenna, hopefully tonight, and see if I can lock things in. 24 was almost unwatchable last night.


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## shanewalker (May 4, 2005)

Likewise, add me to the list here in Chicago.

While my 811s get all 15 digital locals, my 942 will only reliably and artifact-free get the big three networks and channel 11 PBS. Two techs have been out, checked wiring, done A/B compares by swapping out an 811 into the 942s spot, even pulling sat from the loop and just having a straight antenna run, no change. Hope its software as has been suggested elsewhere here. And that a fix is coming soon...


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## dmodemd (Jul 5, 2002)

Big suggestion for ya:

I found on my 6000 (and still on my 811) that if I attenuated the signal I could pick up another 10 points on the scale. The best thing to do is get a variable attenuator at Radio Shack and put it on the cable. That way you can adjust the dial and see if you get any improvement. I first discovered the improvement when I was using a splitter that had a -5db attenuation on it and found a couple stations just wouldnt come in WITHOUT the splitter!

You may find that it will make some stations better, others worse, but I was able to get a happy medium that made an overall improvement. Some other people have tried this and noted no improvement so your results will vary.

Now, usually you need to do this if you live too close to the tower and the signal is too strong but I live 40-50 miles out so you wouldnt think I need to do this but it helped. Its something to try...

If it doesnt work return it, its only like $5-$10.

Lee


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## shanewalker (May 4, 2005)

Done. Thanks for the suggestion. For $10, I'll give it a try. My wife called and she was only a couple of blocks from Radio Shack, so I had her pick one up on her way home. We'll see if it makes a difference...

Their variable attenuator is listed as a TV/CATV Attenuator, hopefully that'll work for satellite/antenna. I'm putting it on the post-diplex lead that runs into the 8VSB antenna in port, right?


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## Rob Glasser (Feb 22, 2005)

[email protected] said:


> Done. Thanks for the suggestion. For $10, I'll give it a try. My wife called and she was only a couple of blocks from Radio Shack, so I had her pick one up on her way home. We'll see if it makes a difference...
> 
> Their varialble attenuator is listed as a TV/CATV Attenuator, hopefully that'll work for satellite/antenna. I'm putting it on the post-diplex lead that runs into the 8VSB antenna in port, right?


I'd be curious to know if this works for you. I tried an attenuator with my 921 and it did not help my reception strength at all. This was when I had a CM4228 and we not able to lock in all channels due to the more narrow reception path of the CM4228. Switching to a CM4221 widened my reception and I was able to lock in everything, on the 921.


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## shanewalker (May 4, 2005)

A big thanks to dmodemd!

Follow-up on my OTA issues...a $9.99 variable attenuator from Radio Shack seems to have done the trick. Seems things were overmodulated, when set to medium strength, bingo, I get good artifact-free lock on all the channels. I'm watching 32.1 Fox ("House") right now, and though the signal has cut out for a split second and there were some hints of audio drop-out, that might just mean I need to do some minor tweaking (or when the mandate kicks in the broadcast power might jump and I'll have to reset this whole thing anyway).

So, I guess the 942 has a tuner much more sensitive to overpowered/overmodulated signals coming down the wire. I'm going to call E* tomorrow and let them know, as many folks might benefit from the same relatively simple fix (until they can [hopefully] provide a permanent remedy via software update, etc.). Might be that certain markets/locations are more prone to 8VSB overmodulation and that's why it seems to be affecting only pockets of 942 owners...but again, I'm no expert on these matters, so my language or logic could be way off.


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## DRJDAN (Apr 28, 2002)

Does the overpowered/overmodulated signals come over the air from the TV stations or from the type of antenna being used?


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## Bichon (Jun 5, 2003)

I'm not sure you are coming to the right conclusion when you assume your signals were overpowered or overmodulated. My guess would be multipath. Multipath happens when TV signals reflect off of buildings and other objects; the weaker reflected signal reaches your antenna a fraction of a second later than the original. On an analog TV, it causes ghosting. On a digital signal, it can cause dropouts, glitches and other problems. An attenuator might help (a digital signal only) by lowering the reflected signal to a point where it is no longer detected by the receiver. The direct signal would also be reduced, but presumably it is still strong enough to be received properly.


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## dmodemd (Jul 5, 2002)

Well here is what I think happens...

We didnt talk about the amp. Make sure you use a fairly high powered amp with a variable adjustment. Turn the attenuater (which is AFTER the amp of course) all the way down. Then turn up the amp gradually and watch it get stronger and stronger until it all of a sudden falls apart, then step it back a notch. Then start to turn up th attenuator until things get the best. Its trial an error. THEN you will find you may have hosed some other channels, so start with your favorite channel and adjust from there so you get them all the way you want them.

I think what happens here is the amplifying then the attenuation helps filter out the week multipath signals. Thats my guess. Also explains why it works for some and not others. Some people may just not be having multi path issues and instead have obstructions or just weak signals.

Glad it helped! Everyone needs to at least try it. (but you need an amp of course too!)

Lee


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## dmodemd (Jul 5, 2002)

Another trick I learned....

If you dont have a rotor but have stations in two main directions (live near two cities), you CAN splice two antennas together! I had my main antenna and amp, then after the amp used a common splitter and spliced in the basic bow tie antenna from Radio Shack. After strategically placing it I was able to get both my sets of channels in adequately. The splitter actually HELPED the signal because it added in the attenuation. his is how I discovered the above trick. I found when I took out this splitter things got WORSE! it was weird... Your signals wont be as good as a good antenna on a rotor with a good amp, no splitter, and a variable attenuator, but it is a good hack if you dont want to use a rotor.

Lee


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## dmodemd (Jul 5, 2002)

I had troubles with my local Fox station first. They are notoriously behind on getting up to full power so be patient and that should get better over time, it did for me.


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## Bichon (Jun 5, 2003)

Combining two UHF antennas together with a splitter (called a combiner when hooked up that way) willy-nilly is not a recommended practice. The problem occurs when a station is strong enough to be received on both antennas. Since the antennas are not stacked, the received signals will be slightly out of phase with each other. The interaction of the two signals causes an effect similar to multipath. I'm glad it worked for you, but others should be aware that it isn't an accepted practice; results will vary based on the relative position of the two antennas and the amount of cable between each antenna and the combiner. Folks who don't want to play roulette with their signals would be better served with a rotor or an A/B switch.


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## shanewalker (May 4, 2005)

I went down the overmodulation road because of the high signal strengths of a couple of the affected channels...they were pegging at 94-100% pre-and-post attenuator. The Winegard antenna set-up I have has no pre-amp other than the power provided by the E* boxes. I know that 12V comes from the 942, not sure about the 2 811s...my V* boxes (also 3) provided power to the line as well, but supposedly in a different manner than the Dish hardware. Again, not clear on the specifics. I agree that multipath was probably part of the problem--I have several large condo/apartment buildings nearby (though nothing really much taller than our 4-story unit) and we're 7 miles due north of downtown Chicago, likewise Lake Michigan is only 2 blks away, which could account for some 'bounce' interference. The signal strengths are all rock solid and always have been, however, so, again, that's where my thinking that overmodulation might have been adding to the problem. I have the attenuator set at 3/5 to max and reception seems quite solid across the board...we'll see what happens with any further software updates and when all the channels go full power.


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## srbigbutt (Apr 25, 2005)

Everytime I think its going to start working steady it starts having issues again. Let us know if it works strong for a week or so.


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## Rob Glasser (Feb 22, 2005)

Just to update my situation. I too went and bought an antenuator last night, hooked it up and was able to get my local FOX affliate locked in without drop outs. It caused my "signal" on that station to drop about 10% but it was more stable. The downside, is it dropped 2 other stations as well, and they started expierencing regular dropouts. I'm going to have to play with this and antenna location some more to try and lock everything in. I can definetly see now that the 942 is way more suseptible to multi-path and I really really hope this is something that can be fixed via a software update and SOON.


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