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ke4pym
Premium
join:2004-07-24
Charlotte, NC
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reply to alkizmo

Re: Hopeless or possible? HDTV OTA

I think you can probably bring that station down with the a-fore-mentioned high gain antenna TheTechGuru posted.

Couple it with a proper in-line pre-amplifier (this would be a good one to start with - »www.solidsignal.com/pview.asp?mc···79001809 ) near the antenna and it'll be a wicked installation.

Remember, amplifiers amplify noise along with signal. So, if you have a crappy signal at the output of your antenna, that crappy signal is going to be worse after going through the amp.

Consider using quad-shield coax between your antenna, pre-amp and then your distribution block.

BUT - if you try to use this combination for any of your closer stations, you're going to overload the front end of your tuner section and probably won't have much to work with to get a station (too much signal is just as bad as not enough).

@Jack - Water and land have very different signal propagation characteristics - the two really can't be compared.


alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
said by ke4pym:

I think you can probably bring that station down with the a-fore-mentioned high gain antenna TheTechGuru posted.

BUT - if you try to use this combination for any of your closer stations, you're going to overload the front end of your tuner section and probably won't have much to work with to get a station (too much signal is just as bad as not enough).

Well, from all the info from you guys, what I might do is buy the 91XG for the far away stations, and a cheaper smaller UHF/VHF antenna for the local stations. They are basicall 90 degrees apart in direction, so instead of buying a motor, I'd just install two antennas pointed in two directions, and the signal strenght issue would be resolved.

I'm going to shop for where to buy them at the best price, and start reading up on baluns, pre-amps, and combining the two antennas.

ke4pym
Premium
join:2004-07-24
Charlotte, NC
Reviews:
·Northland Cable ..
·Time Warner Cable
·ooma
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If you wanna get really freaky:

Find a preamp with 300-ohm input. Then get some of the old school twin lead cable to run from the antenna to the pre-amp. Skip the balun all together. Switch to 75-ohm coax after the preamp on the mast.

Twin lead has some of the best signal interference rejection out there.

You *have* to use stand offs though. The cable can't come anywhere near your mast.

Careful with the extra antennas. Those can induce multipath issues. But most modern tuners are pretty well equipped to handle that kind of thing now.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to ke4pym
said by ke4pym:

@Jack - Water and land have very different signal propagation characteristics - the two really can't be compared.

Thanks but I didn't ask for a critique of my statement. I was just clarifying how I am presently using my setup which is only backup as I use Directv for my primary source. I know the performance very well is different land vs water.

The Channel Master CM4228 coupled with the Channel Master RM7777 RF Amp is a great combo. Good quality amps don't overload the tuners so that is a non-issue using a good amp and quality receiver.


TheTechGuru

join:2004-03-25
TEXAS
kudos:2
Reviews:
·HughesNet Satell..
·WesTex Connect
reply to ke4pym
said by ke4pym:

If you wanna get really freaky:

Find a preamp with 300-ohm input. Then get some of the old school twin lead cable to run from the antenna to the pre-amp. Skip the balun all together. Switch to 75-ohm coax after the preamp on the mast.

Twin lead has some of the best signal interference rejection out there.

You *have* to use stand offs though. The cable can't come anywhere near your mast.

Careful with the extra antennas. Those can induce multipath issues. But most modern tuners are pretty well equipped to handle that kind of thing now.

Meh, I prefer a inline line powered preamp screwed right into the matching transformer on the antenna.
--
CompTIA Network+ Certified


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
reply to alkizmo
That is almost exactly what I have done (two antennas at 90 degree angle to each other). Ideally those antennas should be spaced 2 * wavelength apart to prevent them from effecting each other in unpredictable ways.

That is usually not a problem for the short wavelength of UHF but the wavelength for VHF band III (VHF-Hi) is up to 1.7 meters (VHF band I or VHF-Lo would be up to 6 meters!).

I solved this by having one antenna on a roof antenna mast while the other antenna is on a chimney mount.

Don't sweat it too much if you can't separate them that far, just know that for best results you maintain some distance between them.

The other advise I read while planning my setup was to keep the length of the antenna cable from each antenna to the splitter/combiner exactly the same length (to keep signals arriving on both antennas in phase).
--
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Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to alkizmo
said by alkizmo:

Well, from all the info from you guys, what I might do is buy the 91XG for the far away stations, and a cheaper smaller UHF/VHF antenna for the local stations. They are basicall 90 degrees apart in direction, so instead of buying a motor, I'd just install two antennas pointed in two directions, and the signal strenght issue would be resolved.

I'm going to shop for where to buy them at the best price, and start reading up on baluns, pre-amps, and combining the two antennas.

With the changeover most stations are on UHF so a VHF antenna will do nothing for you. We have one station here that reverted to their original VHF Channel 13 but being it's so high I can receive it with my UHF antenna though the signal level is much lower than the other UHF channels.

Don't waste your money. Just get a good UHF antenna and amp.

Check these out and shop for price. Solid Signal has them or at least they did when I bought mine from them.


Channel Master 4228HD 8-bay HDTV/UHF TV Antenna (4228-HD)

Or better here:

»www.channelmasterstore.com/Outdo···s/20.htm


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to ke4pym
said by ke4pym:

If you wanna get really freaky:

Find a preamp with 300-ohm input. Then get some of the old school twin lead cable to run from the antenna to the pre-amp. Skip the balun all together. Switch to 75-ohm coax after the preamp on the mast.

Twin lead has some of the best signal interference rejection out there.

You *have* to use stand offs though. The cable can't come anywhere near your mast.

Careful with the extra antennas. Those can induce multipath issues. But most modern tuners are pretty well equipped to handle that kind of thing now.

Why would someone want to revert back to 1950's technology with 300 ohm twinlead? You'll have ghosting and multi-path freezes and blocking. The preamp goes right at the antenna so there's really no need for twinlead.


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
reply to Jack_in_VA
I have the CM 4224 (basically half of the CM 4228) and can recommend it but the antenna linked to by TheTechGuru See Profile has 4dB more gain then either the CM 4228 or the HD-8800. If those specs are correct it would be the better choice.
--
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Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
reply to leibold
said by leibold:

That is almost exactly what I have done (two antennas at 90 degree angle to each other). Ideally those antennas should be spaced 2 * wavelength apart to prevent them from effecting each other in unpredictable ways.

That is usually not a problem for the short wavelength of UHF but the wavelength for VHF band III (VHF-Hi) is up to 1.7 meters (VHF band I or VHF-Lo would be up to 6 meters!).

I solved this by having one antenna on a roof antenna mast while the other antenna is on a chimney mount.

Don't sweat it too much if you can't separate them that far, just know that for best results you maintain some distance between them.

The other advise I read while planning my setup was to keep the length of the antenna cable from each antenna to the splitter/combiner exactly the same length (to keep signals arriving on both antennas in phase).

What are you receiving on VHF? We have one channel that reverted to VHF-13 after the changeover at the request of the station and FCC to avert interference with another station. Otherwise everything is UHF.


alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
reply to leibold
Ok let's focus on getting to the 85 miles away stations on UHF only. I can deal with the local stations with a second smaller antenna placed away from the big one.

I'm still torn here on whether I go directional (XG91) or multi-element (HD 4228).

They are both available locally to me at the same price (100$).

TechGuru recommended directionals yagis.
Leibold recommended multi elements.
Then everyone else is on either camps.

What do?

Notes: Tree will not come down (if it makes a difference for either antenna).


fartness
computersoc dot com
Premium
join:2003-03-25
Look Outside
Buy both and return one?


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET

1 edit
reply to Jack_in_VA
said by Jack_in_VA:

What are you receiving on VHF?

KGO (ABC) and KNTV (NBC) are transmitting in VHF band III. Last time I checked there was even a pending application to transmit on channel 6 (VHF band I) but I don't see that any longer.

The furthest away station that I'm receiving is KRCB (73 miles) on UHF. All other stations are half that distance or closer.

Edit: I should probably add that neither of my two antennas has a pre-amp. I do however use a cheap amplified splitter inside the home.
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alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
reply to fartness
said by fartness:

Buy both and return one?

One of them is from a store with no return unless defective (exchange only) policy.

Also I'd rather not be playing on my roof switching back and forth between two antennas :P
AND, the tree doesn't have leaves anymore at this time of the year, so I wouldn't be able to test how they behave differently in summer time.


fartness
computersoc dot com
Premium
join:2003-03-25
Look Outside
Are you trying to pick up a station from Ottawa? Is it on satellite or cable?


leibold
Premium,MVM
join:2002-07-09
Sunnyvale, CA
kudos:10
Reviews:
·SONIC.NET
reply to alkizmo
said by alkizmo:

TechGuru recommended directionals yagis.
Leibold recommended multi elements.

Based on the specifications the XG91 is the clear winner. I just recommended what I have experience with.

Before purchasing the antenna also check the space requirements which are very different for those two types of antennas.

While I don't advocate cutting down the tree I do agree on avoiding the tree in the straight line between antenna and transmitter. Consider a different location for the antenna mast or using a taller one.
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resare

join:2012-11-07
Greenfield Park, QC
reply to alkizmo
trees DO matter !

I get better signal in the winter months (no leaves in the trees).


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
said by resare:

trees DO matter !

I get better signal in the winter months (no leaves in the trees).

Leaves play heck with the UHF signals. Mostly multipath problems.


alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
reply to leibold
said by leibold:

While I don't advocate cutting down the tree I do agree on avoiding the tree in the straight line between antenna and transmitter. Consider a different location for the antenna mast or using a taller one.

To go above the tree,I'd have to go a good 70 feet up.

HOWEVER, if I move the antenna away from the originally planned location, and put it over my garage, I could avoid the tree from the LOS. I'd go down to 10-15 feet elevation, but I guess losing 15 feet is better than having a tree in the way.

Jack_in_VA, that amp.... too TOO expensive, woah

ke4pym
Premium
join:2004-07-24
Charlotte, NC
Reviews:
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reply to Jack_in_VA
said by Jack_in_VA:

said by ke4pym:

@Jack - Water and land have very different signal propagation characteristics - the two really can't be compared.

Thanks but I didn't ask for a critique of my statement. I was just clarifying how I am presently using my setup which is only backup as I use Directv for my primary source. I know the performance very well is different land vs water.

The Channel Master CM4228 coupled with the Channel Master RM7777 RF Amp is a great combo. Good quality amps don't overload the tuners so that is a non-issue using a good amp and quality receiver.

Then you really shouldn't have brought the two up as they're irrelevant to the discussion at hand.

An amp's quality, while important, isn't the case here. If it amplifies a strong (read: local) signal too much, you're going to overload the front end of the receiver. While there are amps that have gain control, I don't know of any preamp based systems that offer AGC (that wouldn't compete with the tuner's own AGC circuit).

And just because you may have a quality display, it doesn't always mean its going to have a quality receiver on board. Which, again, if presented with too much signal (IE trying to amplify local signals) will overload. This is true for any receiver. Not just TV.

If the station's xmitter is indeed on a 3000 foot mountain, with say even a small 100' tower, I doubt a 30' tree is going to present much of an issue. Unless, it's like, 100' wide or something.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

2 edits
said by ke4pym:

said by Jack_in_VA:

said by ke4pym:

@Jack - Water and land have very different signal propagation characteristics - the two really can't be compared.

Thanks but I didn't ask for a critique of my statement. I was just clarifying how I am presently using my setup which is only backup as I use Directv for my primary source. I know the performance very well is different land vs water.

The Channel Master CM4228 coupled with the Channel Master RM7777 RF Amp is a great combo. Good quality amps don't overload the tuners so that is a non-issue using a good amp and quality receiver.

Then you really shouldn't have brought the two up as they're irrelevant to the discussion at hand.

An amp's quality, while important, isn't the case here. If it amplifies a strong (read: local) signal too much, you're going to overload the front end of the receiver. While there are amps that have gain control, I don't know of any preamp based systems that offer AGC (that wouldn't compete with the tuner's own AGC circuit).

And just because you may have a quality display, it doesn't always mean its going to have a quality receiver on board. Which, again, if presented with too much signal (IE trying to amplify local signals) will overload. This is true for any receiver. Not just TV.

If the station's xmitter is indeed on a 3000 foot mountain, with say even a small 100' tower, I doubt a 30' tree is going to present much of an issue. Unless, it's like, 100' wide or something.

Did I say I had a quality display with a quality tuner? I don't think so. The quality of my receiver/tuner is irrelevant. I haven't seen receivers overload on strong signals in maybe 40 years. I don't think the OP has to worry about that unless it actually happens to him. If it does it's easy to address.


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

2 edits
reply to alkizmo
said by alkizmo:

said by leibold:

While I don't advocate cutting down the tree I do agree on avoiding the tree in the straight line between antenna and transmitter. Consider a different location for the antenna mast or using a taller one.

To go above the tree,I'd have to go a good 70 feet up.

HOWEVER, if I move the antenna away from the originally planned location, and put it over my garage, I could avoid the tree from the LOS. I'd go down to 10-15 feet elevation, but I guess losing 15 feet is better than having a tree in the way.

Jack_in_VA, that amp.... too TOO expensive, woah

Not only that it comes from the UK and the exchange rate impacts it.

In my CB years one of the station engineers was a friend of ours put a CB antenna (Big Stick) 900 ft up their 1140 ft tower. 900 ft because we bought a 1000 ft reel of coax and needed 100 ft to get from the tower to transmitter bldg. As the old CBers used to say we could "Blow Smoke".

That said sometimes height is not the answer to good reception. In the early days of TV one of my neighbors worked for an appliance store (Wards TV) single store parent of Circuit City. He had an antenna mounted on a trailer with a crank-up tower. He would come to the home and crank the antenna up and down until the "sweet" spot was found. That's the height he would install the antenna.

At first we only had one station that carried all three networks then 3 stations that were not close together. They sold a "Richmond" special which consisted of 3 separate antennas for those who didn't want to invest in a rotator. One for channel 6, Channel 8 and channel 12. Each was mounted on a single mast with proper vertical spacing and aimed at the correct tower.

Here even with Directv they did not broadcast our locals in HD so the only way was to put up an antenna. For several years we experimented with the help of the station engineer from a LINTV station. It was very interesting and a lot of us including the stations learned a lot. Even now the PQ with the Antenna is a little better than that on Directv but I think my DVR is screwing up my main tv because my tv in the bedroom has much better PQ.

I look at 47 miles to the Hampton Roads stations and the Richmond stations are about 65 miles. Can only get Richmond with the leaves off the trees.

Bob4
Account deleted

join:2012-07-22
New Jersey
Reviews:
·Optimum Online
reply to alkizmo
Check the antenna pattern. You might be able to get the nearby stations through a sidelobe.

And that mountain is in the Green Mountains, not the Adirondacks. (Although there are TV transmitters on Whiteface Mountain [4865 feet] in the Adirondacks. They're frequently listed as being in North Pole, NY.)


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
said by Bob4:

Check the antenna pattern. You might be able to get the nearby stations through a sidelobe.

+1

telco_mtl

join:2012-01-06
reply to alkizmo
said by alkizmo:

said by fartness:

Buy both and return one?

One of them is from a store with no return unless defective (exchange only) policy.

Also I'd rather not be playing on my roof switching back and forth between two antennas :P
AND, the tree doesn't have leaves anymore at this time of the year, so I wouldn't be able to test how they behave differently in summer time.

you bought from that store near the bar b barn eh:P

over here on the south shore im able to get WPTZ, WCAX, WETK, WFFF and WVNY if i point my rotor at mount mansfield, I never looked on a map where the transmitters are but i can get WCFE when i point at the adirondacks, i think they are still at tupper lake, also on a clear day i can sometimes get WMTW if i play with the rotor