# How much signal strength needed to lock OTA DTV?



## 0db (Jan 10, 2005)

I'm just getting around to experimenting with OTA reception; I'm in a potentially sketchy area but should have a straight line to the towers in Los Angeles even though they're 60 miles away. I'm getting up to a steady 70 strength in the "point antenna" screen, but even though the channels show "locked" the scan DTV isn't picking them up, and manually adding doesn't make them show up. Is it because the 70 just isn't enough signal, or is this the same bug I've heard of others having? I've seen a couple other people have trouble manually adding DTV stations.


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## ClaudeR (Dec 7, 2003)

I haven't had any luck under 100. Signal comes & goes. Those over 100 are OK.


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## Mark Lamutt (Mar 24, 2002)

I'm able to successfully lock Denver stations in at 65 and above. If you're having problems with higher levels than that, you may be running into a 921 bug, or you may be running into multipath problems.


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## Ron Barry (Dec 10, 2002)

I am in SoCal and I am able to lock on as low as 60 based on the 921 numbers. Wonder if you are possible getting some multipathing?


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## Cyclone (Jul 1, 2002)

I still wish that they would change the units of the Signal Strength meter to a 0 - 100 scale instead of this 0 - 125 that they are using now. It is not very intuitive.


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## 0db (Jan 10, 2005)

But as long as it indicates "locked" (which it does) it should show up on the program guide when I hit "save" if I'm manually adding it, right? No matter how good a signal I'm seeing, it won't let me manually add anything! I've tried full reboot, and restoring factory settings... it adds analog just fine and it will add the one station it spots when i scan DTV stations. I'm thinking about trading this in for a replacement and if it's not better, I'm going back to DTV and I'll just have to wait until the HD10 drops in price.


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## invaliduser88 (Apr 23, 2002)

Only station I consistently have problems with is PBS (low power VHF band) 60-65 signal will give me lock with intermittant loss.


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## 0db (Jan 10, 2005)

OK, I guess i just answered my own question; I CAN manually add the one local station I get at 125 signal strength; it just won't touch the others in the 70s. Kind of disappointing, I guess it's time for me to try something a little bigger than a Silver Sensor.


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## Harkonen (Jan 5, 2005)

I am successfully locked in on anything around 65 or so. As earlier posters have mentioned, the HD OTA offering is plenteous here in the Bay Area.

Interestingly, channels that were slow to lock or difficult to maintain with my 811 are rock solid with the 921. This has been a pleasant surprise.


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## invaliduser88 (Apr 23, 2002)

Yeah, my 921 handles OTA much better than my 6000 did here.


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## JM Anthony (Nov 16, 2003)

Not that I'm an expert, but I don't think what we're seeing on the readout is signal strenght, but rather signal to noise ratio. Or at least that was the lecture I got earlier today from the guy who did my antenna install. Whatever you call it, I'm also one of those guys who can get a consistent lock on locals in the low 80's.


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## ClaudeR (Dec 7, 2003)

Mark Lamutt said:


> I'm able to successfully lock Denver stations in at 65 and above. If you're having problems with higher levels than that, you may be running into a 921 bug, or you may be running into multipath problems.


Good point Mark. My Yagi is not pointed at the stations with lower than 100, so I must be picking up a multipath signal. The 921 tends to brain fart with poor signal.


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## 0db (Jan 10, 2005)

It seems that my signal isn't actually steady at 70, it's bouncing 70-66-74-0-70 (I was in the attic, with a spotter downstairs). It doesn't vary much within about a 30 degree azimuth, so I think I'm picking up a stray reflection rather than the actual signal from the towers. My attic location is somewhat near my metal central heater - is it possible that this amount of metal is causing reflection issues right inside my attic? I have no large structures anywhere near that could be doing it.


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## Mark Lamutt (Mar 24, 2002)

Absolutely possible, and probably likely, 0db. With my original antenna setup, I was actually receiving a channel by picking up a reflection off of my Dish. When I moved the dish, I lost the channel until I moved my antenna to a different location.


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## madbrain (Dec 10, 2004)

This week many channels out of SFO were operating at half power due to the transmitter failing. Not a good week to install my 921 . Yet, it had no problem locking the stations (KQED and KGO) even at only 70 signal strength. There weren't any dropouts.

However, the 921 can't stay locked on KCSM which is at about 60 strength. There is a lot of dropout on that channel (43.1 and .2) . My Samsung SIR-T165 on the other hand does not get any dropout. Both are hooked up to the same antenna (Channel master 4221) .


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## 0db (Jan 10, 2005)

Thanks guys, this reinforces my opinion that I likely need to extend my RG6 into attic #2 (over the garage) where there's nothing else to interfere. Also I think I'll end up stepping into a Channelmaster 3020 or something similar, I need all the help I can get. The Silver Sensor seems to be out of its league pulling in distants at 60 miles.

Appreciate all the positive feedback! Tomorrow is another day!


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## flmilkfarmer (Nov 14, 2004)

Is there a way to keep the signal strength displayed instead of the short few seconds you see it when you tune to the channel?


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## 0db (Jan 10, 2005)

only through the "point dish" or "add DTV" menus.

Picked up a Channelmaster 3020, may put it up tonight and see how things look. No success thus far with the silver sensor.


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## bolco (Jun 11, 2002)

On mine, while doing a manual add, it doesn't matter if it says "locked" or not. It wont work unless the OTA DT station shows "LOCKED AND ACQUIRED." Just my experience.


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## ibglowin (Sep 10, 2002)

If your 60 miles away from the towers you need an antenna rated for "deep fringe". The tiny set top box antenna's are meant for people right in the city and or near the source more or less. (YMMV as they say) I wouldgo for the antenna that has the highest signal gain, and then buy a good, high quality pre amp as well such as those made by channel master or winegard. Expect to pay $50-60 for one. It will make all the difference in the world in those stations you are having problems locking and holding on to.


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## flmilkfarmer (Nov 14, 2004)

0db said:


> only through the "point dish" or "add DTV" menus.
> 
> .


 I tried this but get no signal on any channel even though they are at 100+ when you tune to that channel and get the signal indicator in the upper right corner.


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## Mark Lamutt (Mar 24, 2002)

You need to enter the actual broadcast channel number, not the remapped channel number. You should be able to get that list from www.antennaweb.org


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## flmilkfarmer (Nov 14, 2004)

Mark Lamutt said:


> You need to enter the actual broadcast channel number, not the remapped channel number. You should be able to get that list from www.antennaweb.org


 I advanced 1 channel at a time and never got any signal.


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## Mark Lamutt (Mar 24, 2002)

I don't know what to tell you, then. Try rebooting and then doing it again. If the browse banner is showing signal strength for your channels, both the Add DTV entry box and the Point Dish screen will as well.


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## 0db (Jan 10, 2005)

ibglowin said:


> If your 60 miles away from the towers you need an antenna rated for "deep fringe". The tiny set top box antenna's are meant for people right in the city and or near the source more or less. (YMMV as they say) I wouldgo for the antenna that has the highest signal gain, and then buy a good, high quality pre amp as well such as those made by channel master or winegard. Expect to pay $50-60 for one. It will make all the difference in the world in those stations you are having problems locking and holding on to.


I'm an idiot. I put up the CM3020 (massive, deep fringe rated) and still got no locks except the one that's 7 miles from home. After pondering the situation I came to the shocking realization that I'm putting up my antenna in my attic of a STUCCO HOUSE which naturally has wire mesh wrapped all the way around it. :nono2:

I'll be exploring rooftop options in the next 24 hours or so.


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## TVBob (Dec 19, 2003)

flmilkfarmer said:


> Is there a way to keep the signal strength displayed instead of the short few seconds you see it when you tune to the channel?


Yes. Press the *BROWSE* button (right arrow).


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## TVBob (Dec 19, 2003)

0db said:


> I'll be exploring rooftop options in the next 24 hours or so.


That's the way to go. Outdoors will be _much_ better. Good luck and let us know how it works.

If your local UHF _analog_ signals are pretty solid and free of major ghosts (mulitipath), you should have no trouble receiving the digital stations that are nearby in frequency. On the DVR-921, any signal falling below 60 (on a 0-125 scale) will cause an immediate drop-out. On a Dish 6000, any signal below 50 (on a 0-100 scale) will do the same. The 921's OTA receiver is much better than the 6000's, but still not as solid or as quick to lock on as the integrated HD tuner in my Sony TV (which was manufactured over 3 years ago!)

BTW, homeowners associations cannot stop you from putting up an ordinary outdoor TV antenna (12' above the roof line max), even if they publish restrictions that say "no outdoor antennas." Any such restrictions are preempted by the FCC's Over-The-Air-Reception-Devices (OTARD) Rule. See this FCC fact sheet.

I'm 50 miles from the tower in San Francisco , and the little TV antenna pictured in my Avatar just would not cut it. I recently replaced it with a Winegard PR-9032 UHF-only high gain antenna, and this made a huge difference. I also picked up the Channel Master CM-7775 UHF mast-mounted pre-amp, but I haven't installed it yet and it seems I may not need it. Yeah, I still get a few momentary drop-outs when a plane flies overhead or a big truck rolls by. I doubt a pre-amp will help with that problem, though.


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## ibglowin (Sep 10, 2002)

That could attenuate the signal a bit!


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## 0db (Jan 10, 2005)

ibglowin said:


> That could attenuate the signal a bit!


Even if it's not directly in the path of the signal (antenna is pointing out through the sloped plywood-ceramic tile roof at the moment), I suspect it's going to create some crazy reflections in between all the walls!


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## Michael P (Oct 27, 2004)

flmilkfarmer said:


> I advanced 1 channel at a time and never got any signal.


I've been trying to add a station that I get a lock on bet never acquires. The signal strenght fluctuates from 70 to 0 to 100 and back to 65. It's probably those dips to 0 that blows the acquisition. The station is only a few miles away from here but they are on an "STA" licence at only 1000w on a short tower at their studio. I have an outdoor omnidirectional "saucer" antenna on a 20' mast on my chimney. I get too much multipath with this antenna - but I can't change it until spring.

Anyway, I found from my numerous attempts to get this station acquired that the "Add DTV" screen is made to get only one station at a time (i.e. entering several channels one after the other returns "0" readings even though you know for a fact that at least some of these channels have strong signals). Also there is a delay in the readings if you should enter a second channel - the readings from the first channel entered "sticks" on the bar graph longer than the channel number displayed. (I gave myself false hope by entering a weak channel after a strong one).


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## The Guv (Dec 14, 2004)

ibglowin said:


> If your 60 miles away from the towers you need an antenna rated for "deep fringe". The tiny set top box antenna's are meant for people right in the city and or near the source more or less. (YMMV as they say) I wouldgo for the antenna that has the highest signal gain, and then buy a good, high quality pre amp as well such as those made by channel master or winegard. Expect to pay $50-60 for one. It will make all the difference in the world in those stations you are having problems locking and holding on to.


I also live 60-70 miles from the broadcast towers in my main TV market (Quad Cities IL/IA) and I get consistently strong signals (115-125) from the HD channels offered locally (NBC, ABC, PBS, FOX, WBNet).

A year ago, before I got my HD monitor and my 921 receiver, I had a large directional Winegard antenna with rotor put on my tower. Besides recieving TV from the Quad Cities market to the north of me, I can also recieve signals from the Quincy IL market and also sometimes from Peoria IL and also sometimes from other areas in Northern Missouri and Cedar Radids IA. It's all working great Beav!

Now, if only my local CBS affiliate will go to HD, I will be set! But then, I really don't care for or watch CBS anyway (except for the ocassional must-see sports game), since left-wing biased Dan Rather is still there. :nono2:


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## Skyburn (Nov 30, 2004)

I thought since I have been through all this very recently, I'd post my findings for the good of the community:

- I live just on the northern fringes of Fort Collins Colorado, 55 miles due north of Denver.
- I have a 921, and decided to try to get OTA stations with it, so I started out by buying a small UHF/VHF antenna from Walmart for $30 -- that didn't do anything good, so I decided to get crazier.
- Bought a RatShack Model: VU-90 XR antenna, 80" boom for about $55.
- Just as a quick test, I opened it up in my basement, unfolded the elements, and could actually lock a couple of channels (inconsisently) from Denver (I think at the time, I could lock the WB (KWGN) and FOX (KDVR) -- both DT channels.
- I decided to try an attic installation, and this worked better than in the basement, but still somewhat inconsistent --I'd get signal strengths in the 50-60 range, but they would bounce up and down a lot. I also had a cable-run issue, and based on that decided the thing had to go on the roof. Plus, someone pointed out to me that your roof has A) lots of shingles and B) a million nails to hold those shingles down, in a nice, symmetrical pattern that would seriously introduce multipath problems.

So, I made the jump to mounting it on the roof -- all-in-all I probably spend a little over $150 for the antenna, mount, mast, cable, weatherproof F connectors, diplexers etc.

My house is a typical bi-level with gable-roof style construction. I mounted the antenna in a fixed position (no rotor or anything yet), and pointed it due south.

After I did this, I receive 4 different signals -- KWGN-DT/WB 4 out of Denver; KDVR-DT/FOX 31 out of Denver; KBDI-DT/PBS 38 out of Denver (or maybe Longmont) and some channel 15 which I can't figure out what it is yet -- it's locked, but nothing on the channel.

I diplexed the antenna signal onto one of the 3 outputs I have coming out of my Dish DP-Quad LNBF. The other 2 cables are 1: for my 510, and other for the 2nd input into the 921. Un-diplex with another diplexor at the 921 to bring in the 2nd 921 feed and the OTA feed. Other than whatever is inside the DP Quad LNBF, I have no switches whatsoever.

My experience (from having it in the basement, then the attic, then on the roof) is as follows:
- This particular antenna (I was new to all this so didn't really understand it before, others here surely would have at the time) is very directional. Since I live due north of Denver, and that's where most of the OTA Digitals are out of, it would seem the best thing to do is point it due south to get the greatest number of signals. In my case, I didn't even really try other directions. I'm most interested in obtaining FOX anyway...so that works for me 
- One thing that seems to get people really confused is the way the 921 acquires the OTA stations. I was no exception. It was very frustrating when the signals would lock at one point, then not lock at all, or get badly pixelated signals. I finally started to get comfortable with how the signal meter relates to signal acquisition etc. and found that if the antenna wasn't pointed just right, or the antenna wasn't on the roof, I'd see the meter go up to 50 then say 64 then 76, then drop to 0, then back up to 50 etc. and go on and on like this. In this situation, without exception, I wouldn't lock a signal -- just as reported by other people, it seems that if the signal meter pops all the way down to 0, even if just for a split second, the signal wouldn't ever lock.

- Putting the antenna on the roof boosted all of these signals that I'm receiving up to over 100, and they all stay pretty constant -- it made ALL the difference in the world. The picture is absolutely stunning on my Panasonic 42" Plasma -- it's just awesome. HD content from both WB and FOX is exceptional. I don't know how people live without HD! 

I'm a little disappointed that I can't get all the locals this way -- I'd love NBC/CBS/ABC also (oh, and UPN!) -- I'm sure sooner or later I'll see these as well.

Oh -- and to the poster who mentioned that the 921 would only lock onto a signal and actually display a picture from an OTA digital when the "ADD DTV" screen stated "Locked And Acquired" as opposed to just "Locked" -- that's my exact experience as well -- seems it has to say both to actually get a picture that is viewable.

That's my story -- it's an evolving thing for me, but overall it's pretty cool that I can get these Denver stations all the way up here, and with such high quality. I almost can't watch SD channels anymore!

I've recently been having some odd recording issues with the 921, like timers not firing (some OTA, some DBS) -- I'll see a message after the time to fire has come that states something like the timer/channel to record is not authorized or something like that. Last night I set a manual timer to record SciFi off Dish, extend time for 15 minutes or something after event ends; this morning it was still recording -- 900 some minutes of a recording. Couldn't even stop the recording via the DVR menu, had to power-button reset the 921, then it stopped recording. Ah well...at least it works most of the time!

- Joe


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