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Discussion Starter · #1 ·
I have an existing RS antenna for local channels mounted on my chimney. I get the 4 main networks on VHF pretty good. My UHF isn't so good. Channel 20 comes in very clear, but the higher I go up the scale, the worse it gets. Channel 50 is very snowy. 22 and 26 are a little less snowy.

I went to RS and got an amplifier and tried it, but it just made the VHF channels much worse, and did very little for the snowy UHF ones.

Here is my question. Given the information above, which of the following would most likely be the situation;


1) Good antenna, needs to be positioned better.

2) Not good antenna, need to have new one installed.

3) Just need better UHF antenna installed on same pole as existing.

4) Need to have a rotor installed on existing antenna.

5) Need to have new antenna with rotor installed.


The reason I'm so concerned about UHF is because my SAT HD100 is due to arrive tomorrow and I figure if I can't get the regular UHF stations well my chance of getting the HD's is not good.



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Dave B.

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The existing antenna you have probably has little gain at UHF frequencies. This will make it tough for reliable DTV reception.


Based on my experiences, I suggest using a separate UHF antenna. According to the FCC Table of Allocations for Washington DC DTV stations, you have all UHF channels - 27, 33, 34, 35, 36, 39, and 48. I don't know how long your mast is, but you may be able to install a UHF corner reflector. If you have about 48" of vertical clearance, why not try the Channel Master 4221? It works exceptionally well and is comparatively cheap at about $25 - $30.


If signals are still somewhat weak, add their accessory preamp - the Titan 2 #7775, which is UHF-only and costs about $69.95 MSRP. Maybe a second coaxial cable will be a pain in the neck, but I have found that DTV reception for now - is best with UHF-only antennas, not combos. (This of course applies only to areas with UHF DTV broadcasts.)


KC
 

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dmbatch,

The snow is due to the fact that your antenna has low gain on the UHF channels and particularly on the higher channels... this will affect reception of the HD signals. I would definitely go with the Channel Master 3021 or 4221 4 bow-tie config. Since you are relatively close to the DC transmitters, you will not need a preamp. The 3021/4221 is a UHF only antenna, but since all the HD signals are on UHF you will not need VHF any longer (look at Ken's post(6wpw)). If you want to get the Baltimore digital stations, you will need a preamp, the CM7775 is the best high gain, low noise, high capacity around. RS amps usually have high noise and some seem to oscillate (not stable).

So, I recommend just replacing your current antenna config with a CM3021/4221 (I bought mine at www.unclejoes.com ($24)). Mount it anywhere, attic, roof, back yard, porch. If you want Baltimore stations, buy the preamp ( www.starkelectronic.com ($69)), mount it on the roof or attic. With the preamp, you may also require an attenuator since the DC stations are close and Baltimore is further away (overload on DC stations so attenuate to optimize DC signals).
 

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Discussion Starter · #4 ·
indadogghouse,


Since you live very close to me, I'll assume you have done all the research work for me. Thanks!!

One more question, If I get the 3021 w/preamp and point it towards the Baltimore stations, will the signal from the DC stations be strong enough without the overload problem, or should I point the antenna at a neutral location between Baltimore and DC and get the attenuator? Looking at the map of station locations from www.antennaweb.org, the Baltimore stations seem to be in the opposite direction from the DC ones.


Also, you say to get rid of my VHF antenna. Does that mean that the HD stations are available all the time, whether they are in HD or not? If not, I would lose my ability to get my local channels when the rain interrupts my Sat reception.



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Dave B.

ODAT


[This message has been edited by dmbatch (edited 03-23-2001).]
 

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Quote:
Originally posted by dmbatch:


One more question, If I get the 3021 w/preamp and point it towards the Baltimore stations, will the signal from the DC stations be strong enough without the overload problem, or should I point the antenna at a neutral location between Baltimore and DC and get the attenuator? Looking at the map of station locations from www.antennaweb.org, the Baltimore stations seem to be in the opposite direction from the DC ones.
The stations shouldn't be opposite from each other, the Baltimore stations are ~45 degrees, the DC ~65 degrees, and PBS digital ~90 degrees. You can point at Baltimore and DC still comes in pretty strong (still overloaded), but then more susceptible to multipath (depending on what's around you). Also PBS digital may lose signal (don't know the beamwidth of 3021, maybe 45 degrees).


I have the DISH 6000 so subchannels may vary.

Channel mappings analog to digital:

2-52 (3 subs) WMAR ABC Baltimore

2.1 (14x9 1080i of SD, 720p HD)

2.2 (4x3 480i of SD)

2.3 (4x3 480i Doppler Radar Map Centered on Baltimore)

4-48 (1 sub) WRC NBC DC

4.1 (16x9 1080i of SD with black bars, 1080i HD(Just LENO?))

5-36 (1 sub) WTTG FOX DC

5.1 (16x9 1080i of SD with black bars, 480p 16x9 shows)

7-39 (1 sub) WJLA ABC DC (NO HD CONTENT or plans to broadcast)

39.2 (4x3 480i of SD) THEY SUCK!

9-34 (1 sub) WUSA CBS DC

9.1 (16x9 1080i of SD with black bars, 1080i HD(just 'bout every show)) Never watched CBS much, watch just about everything now (some of the shows I notice, they take the 4x3 content and crop and sample to display in 16x9 HD-mixed feelings 'bout this, trading content for resolution, but CBS still rocks)

11-59 (1 sub) WBAL NBC Baltimore (most troublesome station to lock onto)

59.2 (14x9 1080i of SD, 1080i HD)

13-38 (1 sub) WJZ CBS Baltimore

38.1 (same as WUSA)


END OF ALL VHF channels, all have digital carriers

22-42 ??? WMPT PBS Annapolis (Local analog 42 causes problems, never been able to tune in)

26-27 (2 sub) WETA PBS DC

26.1 (1080i HD from 7am-12am??, loops of weekly programs, IRELAND loop just recently on, really, really ROCKED!)

26.2 (4x3 480i of SD)

45-46 (1 sub) WBFF FOX Baltimore

45.1 (same as WTTG)

Quote:


Also, you say to get rid of my VHF antenna. Does that mean that the HD stations are available all the time, whether they are in HD or not? If not, I would lose my ability to get my local channels when the rain interrupts my Sat reception.
If you can get all the digital stations, as you can see above, there is no need for a VHF antenna. I've had mine for 3 months, with no problems receiving the DC stations(WJLA 39 went out on a couple days(signal but no content), but who cares?). When I first set up, I put my 3021 on my back porch on a 5 foot pole and pointed in general direction between DC and PBS transmitters, through the neighbor's oak tree (will see about leaves in summer)... rock solid, no significant drop outs, in rain, wind, or snow. I had issues with the Baltimore stations. I needed a preamp, I had to mount the antenna on the roof. Found out higher is not better, because of multipath and other signal interference, overloading, co-channel bleeding, EM interference, and the list goes on. I originally used a Winegard 4800 (29db), couldn't even attenuate the signal(up to 40db) because channel 56 (1.5mi away) oversaturated the input capacity of the preamp. Switched to a Winegard 4700 (19db), better but 56 still saturates a bit... looked to get more chicken wire to increase the rear rejection capabilities (56 is transmitting about 180 deg from the DC/Baltimore channels, probably different for you), couldn't find any. Still had trouble receiving WBFF and WBAL(definitely multipath and interference signal problems) moved up and down all and around the roof, and finally settled that if I wanted ALL the channels reliably, I would have to use 2 antennas, so now I have a 4248(Balt.) and 3021(DC) and 4700 preamp and attenuator... still experimenting; thinking 'bout getting CM 7775 or 0064 preamp (higher input capacity). Looks like 6wpw(Ken) is far enough away to get everything from his attic no less!


Short of it is... I don't know what will happen in your case, everyone seems to be a bit different. If you want, I can loan you my 3021 and one of my preamps for you to try out. Just email me [email protected], won't be able to do it this weekend... maybe on a weekday next week sometime or next weekend. Gotta be ready for NCAA final four!!


Tam
 

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Discussion Starter · #6 ·
Tam,


Man, when you give information you definitely get into some detail. Thanks, it is very helpful.


I hooked up my HD100 last night when it got here. I just put it in place of my old RCA, so I don't have the HD DirecTv channels yet. I also connected my roof antenna. I do get all of the DC area stations, with 48 being the only one that I see drop-outs on. That fits with the higher channels being the hardest to get. 26.1 was showing a special on the Outer Banks in HD and I just can't believe how good that looks. That is what I got my Sony KP61HS10 for in the first place.

I will start with implementing your suggestions by getting the CM3021 and pointing it towards Baltimore and seeing what happens. If need be I'll add the amp and attenuator.


Thanks again,



------------------

Dave B.

ODAT


[This message has been edited by dmbatch (edited 03-25-2001).]
 

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Discussion Starter · #7 ·
Tam,


I did some adjusting to my existing antenna and am able to get all of the DC channels at an 80 to 90 level. I still get dropouts on channel 4.1. If I watch the meter for a few minutes it will drop down to nothing every once in a while and then jump back up to 80 - 82. Is this due to my reception or is the station transmitter just not doing well yet?


I have ordered the CM4221A which is the same as the 3021. I wanted the 4228 but could not find it in stock anywhere, and then noticed it is no longer listed on CM's website. I will install the 4221 and see if it makes a difference. The CM data on the 4221 says that it has the best gain for the higher channels, except for the para-scope 4251 which I think would be overkill for my location.


I'll let you know how it turns out.


Thanks again,



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Dave B.

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Since you said channel 50 was very noisy, and 48 is the channel for digital NBC-4, it could be that there's just not enough signal to consistently lock onto. It could also be multipath.


Definitely, all you need is the 4221, it has good gain for all the UHF channels, good front to back and side ratios. Like I stated earlier, I can stick it in my back deck and get all the DC channels at 80%+ with no dropouts, staring into the neighbor's oak tree.


Stark Electronics www.starkelectronic.com is a good source for everything. You can also try our local fairfax antenna guys... but they may have to order it for you, ends up more time, more money. They could, however, do the installation for you.


Glad to see another person going HD.
 

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My location is Ravensworth Farm, off Braddock Road, just outside the beltway. My orientation is directly in line with Washington & Baltimore transmitters. I started with a Winegard 9095 and 4700 amp with rotor. It did great for Washington with no requirement to move the antenna. Wanting to receive Baltimore stations consistently, I installed a CM 4251 Para-Scope with CM UHF amp (currently no rotor). Using a Panasonic DST-50, I can receive all Washington & Baltimore stations with no reorientation. I have no capability to measure signal strength. Once the leaves appear on the trees it may be a different story, regarding Baltimore reception. I'm not convinced that too much signal (over saturation) is a problem, but I'm not an expert in that area. When the leaves come out or heavy rain, you want as much gain to draw in the strongest signal. Tom


[This message has been edited by Tom Harms (edited 03-27-2001).]
 

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Discussion Starter · #10 ·
Quote:
Originally posted by indadogghouse:
The stations shouldn't be opposite from each other, the Baltimore stations are ~45 degrees, the DC ~65 degrees, and PBS digital ~90 degrees. You can point at Baltimore and DC still comes in pretty strong (still overloaded), but then more susceptible to multipath (depending on what's around you). Also PBS digital may lose signal (don't know the beamwidth of 3021, maybe 45 degrees).


I have the DISH 6000 so subchannels may vary.

Channel mappings analog to digital:

2-52 (3 subs) WMAR ABC Baltimore

2.1 (14x9 1080i of SD, 720p HD)

2.2 (4x3 480i of SD)

2.3 (4x3 480i Doppler Radar Map Centered on Baltimore)

4-48 (1 sub) WRC NBC DC

4.1 (16x9 1080i of SD with black bars, 1080i HD(Just LENO?))

5-36 (1 sub) WTTG FOX DC

5.1 (16x9 1080i of SD with black bars, 480p 16x9 shows)

7-39 (1 sub) WJLA ABC DC (NO HD CONTENT or plans to broadcast)

39.2 (4x3 480i of SD) THEY SUCK!

9-34 (1 sub) WUSA CBS DC

9.1 (16x9 1080i of SD with black bars, 1080i HD(just 'bout every show)) Never watched CBS much, watch just about everything now (some of the shows I notice, they take the 4x3 content and crop and sample to display in 16x9 HD-mixed feelings 'bout this, trading content for resolution, but CBS still rocks)

11-59 (1 sub) WBAL NBC Baltimore (most troublesome station to lock onto)

59.2 (14x9 1080i of SD, 1080i HD)

13-38 (1 sub) WJZ CBS Baltimore

38.1 (same as WUSA)

Tam
Tam,


Here is the info I get from antennaweb.com as to the location of stations relative to my house. The numbers are in degrees with north being 0 and moving clockwise.


Channel mappings analog to digital:

52 (3 subs) WMAR ABC Baltimore 220


48 (1 sub) WRC NBC DC 220


36 (1 sub) WTTG FOX DC 220


39 (1 sub) WJLA ABC DC 220


34 (1 sub) WUSA CBS DC 43


59 (1 sub) WBAL NBC Baltimore 220


38 (1 sub) WJZ CBS Baltimore 220


27 WETA (looks like 2 locations) 48 and 73


42 WMPX 43


43 WPAX 235


So it looks like 27 and 34 are in the opposite direction than all the other stations. If I point my 4221 at the 220 direction, I should get everything but those 2 pretty well. The range on the 4221 is 45 miles, so I'm wondering if that's enough for Baltimore. Probably not.


I'm not sure what to do about 27 and 34. 27 is one of my favorites to use when showing off the HD picture. I don't think the 4221 is going to pick up stations in opposite directions. Maybe I could get 2 of them and multiplex them together on the same cable. I am worried that it would cause multipath problems.


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Dave B.

ODAT


[This message has been edited by dmbatch (edited 03-28-2001).]
 

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Quote:
Originally posted by dmbatch:
Tam,


Here is the info I get from antennaweb.com as to the location of stations relative to my house. The numbers are in degrees with north being 0 and moving clockwise.


Channel mappings analog to digital:

52 (3 subs) WMAR ABC Baltimore 220

48 (1 sub) WRC NBC DC 220

36 (1 sub) WTTG FOX DC 220

39 (1 sub) WJLA ABC DC 220

34 (1 sub) WUSA CBS DC 43

59 (1 sub) WBAL NBC Baltimore 220

38 (1 sub) WJZ CBS Baltimore 220

27 WETA (looks like 2 locations) 48 and 73

42 WMPX 43

43 WPAX 235
This makes no sense, it has to be wrong. You're in Falls Church right? Zip code 22042 or something like that? Baltimore and DC are north and definitely east of you... which means between 0 and 90 degrees bearing. Baltimore is around 45 miles away... all the signals should be coming in around the same bearing ~45 degrees or so. You have it as 220 which means that you're northeast of Baltimore, which puts you in Delaware.

With zip 22042, this is what I see:

DC digitals: 34,36,39,48 (CBS,FOX,ABC,NBC)~43-46 degrees (8 miles)

Balt digitals: 38,46,52,59 (CBS,FOX,ABC,NBC)~42 degrees (43 miles)

WETA digital: 27 (PBS) bearing 62 degrees (4 miles)


If you point your antenna at around 45 degrees, you should be aligned to pick up all the signals. The DC and WETA signal are strong enough definitely, the Baltimore's will be iffy without a preamp.


The www.antennaweb.org map is a bit cluttered and confusing, but believe me, if you are in Falls Church, VA, the above bearings are correct. Don't know why it has 27 transmitting from 2 directions?!


DO NOT point in the direction of 220, you will not be able to pick up any digital channels, you'll be in line with channel 66.


Did you get your 4221 in yet? You will need to align the side without the grating towards 45 degrees. I assume you have a RS yagi VHF/UHF combo now? The <-- end (tail of arrow) should point to 45 degrees.


Again these bearings are in regard to the 22042 zip code (center). It may vary a little from your actual location, but it should be between 40-60 degrees.
 

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Discussion Starter · #12 ·
Mat,


Of course Baltimore is northeast of me. Man, how could I believe that stupid antenneweb.com map. It didn't make sense to me, but I just blindly went by what it said. It even showed some DC stations in the same direction. Duh! I sent you a copy of the map in gif format, you will see what I mean. Your bearings make sense considering I'm slightly southwest of the mall area of DC and I know the transmission towers are all way up in NW almost to MD. And if you continue from there in a slightly more northern route, you run right into, you guessed it, Baltimore. Thanks for the voice of reason.

My antenna wont ship until tomorrow. If I had known how long these guys were going to take to process my order, I would have gone somewhere else. Don't order anything from LNL Distributing Corp.


Thanks again,



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Dave B.

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Yeah, that map is a little confusing... I think what happened is that all the channels were on that 45 degree bearing, but there is just not enough space to print all the channels out on that line bearing so the program printed it out the back end, and of course, coincidently, there was a bearing line completely opposite the 45 and it made it look like the channels were on that bearing. If you look at that 225 bearing line, you can see one of the channels overwritten with another (in blue, near the arrow peak). So the map is right, it just didn't present it well. You could also check www.titantv.com (there's no graphics, but they do give you bearings).

Bummer that the antenna is late in shipping.
 

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Discussion Starter · #14 ·
Mat,


I like the titantv site much better then antennaweb. It tells me that from my address I should set my antenna at 40 degrees. I think I'll start with that when I get my new 4221. It also says I should have a preamp, so I think I'll go ahead and order one. Did you say the CM7775 was the best one for me?


Thanks,



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Dave B.

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Evad http://www.avsforum.com/ubb/smile.gif ,

Since you're so close to the DC transmitters, any high gain preamp you get will probably overload the receiver... not a problem, signal will still be strong but probably less then optimum (you could also attenuate if needed). The real problem is the preamp's input capacity (Max volts it can handle until it saturates). Typically, the higher the gain, the higher the noise, and the lower the input capacity.

These are the preamps I looked at:

Winegard AP-4800 29db, 2.9db noise, 30 mV input

Winegard AP-4700 19db, 2.9db noise, 93 mV input

Channel Master 7775 26db, 2.0db noise, ~200mV input?

Channel Master 7778 23db, 2.2db noise, ~300mV input?


I may have done the math wrong on the Channel Master preamp input capacities. I've used the 4800 and 4700 and have the 7778 on order. The 4800 oversaturated from channel 56 (less than 1 mi from me, i can see it clearly). The 4700 seems to work better. I still have the 4800, you can try it and if it works for you, I'll sell it to you for what it cost me. $46 + $6 shipping, you can also try the CM 7778 when I get it, if necessary. Drop me email if you're interested. You can hook it up to your current RS antenna.


Tam http://www.avsforum.com/ubb/smile.gif
 

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Discussion Starter · #16 ·
Tam, (sorry about the dyslexia)


So, are you saying that the CM7778 with the low noise (2.2) and very high input capacity (~300mv) and 26db of gain provides the best combination of attributes for my situation?


Evad http://www.avsforum.com/ubb/wink.gif


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Dave B.

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Quote:
Originally posted by dmbatch:


So, are you saying that the CM7778 with the low noise (2.2) and very high input capacity (~300mv) and 26db of gain provides the best combination of attributes for my situation?
I think the CM7778 is good, 23db gain, 2.2 NF, high input capacity but unsure of exact number. I have the AP-4800(29db) on hand though if you just want to try it out, and if it works great, it's yours. I got the AP-4800 cheaper than the CM7778 ($46 vs $49).

I'm just saying from my experience, that you really don't need that much gain to catch the Baltimore stations, and the Gain to Noise Figure on these preamps are all very good. The only issue I ran into is the input capacity. For me channel 56 caused a lot of problems because it is soooo close(under 1 mile) to me. For you, I think it's over 2 miles away so it might not affect you as badly. I'm just offering the AP-4800 for you to try before you buy.

By the way, how are you enjoying your HDTV programming?
 

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Discussion Starter · #18 ·
Tam,


OK, I think I'll take you up on that offer. I could put it on my existing RS and see what it does. I still haven't gotten a shipping notice on my 4221. http://www.avsforum.com/ubb/frown.gif


I think 56 is truly in the opposite direction from all the other stations for me since it is between you and me, so I don't think it will be a problem. It is due west of my location.


As far as liking HDTV, her are some thoughts.

I love 26.1 (weta). Not just because the HD picture is so awesome, but because the programming is good too.

The loop on 199 has some things on it that just astound me as far as the picture quality. That whole little preview on the Eco-Challenge is incredible.

I even watched the Sopranos' for the first time last night just because it was on 509. Not bad.

Now I just want everything to be in HD. The only reason I want the Baltimore stations is because of NYPD Blue. You were right about WJLA, the FCC should fine them big time for non-compliance. I am getting 4.1 pretty good now, so I'm looking forward to Fridays Leno show.


Thanks for all the help. Maybe I can come pick up that preamp sometime this weekend, or meet you somewhere nearby.



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Dave B.

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Dave B. I live in Dunn Loring right next to 66 and I am using a Silver sensor antenna sitting about 2.5 feet off of the floor. I do have to move it to the other side of the table for 5 and 7 for DTV. I am using the new Hughes E-86 tuner. FC is lower I believe than where I live. That might be the difference.




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Joe Cole

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Hi dmbatch,


Welcome to the fold.


I live in the Dulles area and get DC and Balto with very good signal... solid around 85 on all channels on my DTC-100.


I have a roofmounted CM4248, a Winegard AP-4800 preamp, and a CM9521 remote controlled rotor. Yes, WETA is awesome for their incredible programs. I especially like the Nova programs. As a quick side note, I tuned to the Balto station for the Super Bowl because they didn't have the static station banner hovering on the left corner of the screen during the whole game. Don't like those things.


Got the antenna and preamp from stark. Got the rotor from consumerdirect which sells the antenna for about $30 ($15 cheaper than stark) and the rotor for about $65 ($25 cheaper than stark).


Looking forward to the Final Four this weekend. Not really a big college ball fan but HD programming has a way of pulling non-fans to the set. http://www.avsforum.com/ubb/smile.gif


Thanks,

Errol


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