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MetHerb
10-Feb-2011, 3:40 PM
I have a Winegard HD-9032 and a Radio Shack Pre-Amp and a generic rotor. I live in the hills of Northeast CT about 30 miles from Hartford, CT and Springfield, MA and about 70 miles from Boston.

Here is a link to my signal analysis:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3de07c16798dbdde

I'm kind of new to getting OTA signals and I'm impressed with what I've been able to get from multiple cities and I'd like to see if I can get additional channels. I can get most of the channels listed with a signal strength of -5.5 or higher. There are a couple that I cannot get due to local terrain and other issues.

Under ideal conditions, I can get signals as low as WSBK from Boston (signal strength listed as -14.9), but it hasn't been sufficiently strong enough to watch. I'd like to have a setup that would make that possible.

What I'm looking to do is revamp my whole setup from top to bottom to get the best possible reception. I'm going to put up a 40' wooden tower and place the antenna's up there. I'd like to add a VHF anntenna. I'm wondering what they optimum antenna setup would be. Separate VHF & UHF? What type of antenna is best? I've heard pros and cons of different antenna types. What about the preamp and cable? What would a dream antenna system look like? :D

My cable run goes from my existing 25' pole on top of a hill about 100-150' to my TV. That wouldn't change.

I'm hoping that experts here and others that have gone through this exercise will be able to help me.

Thanks in advance!

Dave

Tower Guy
10-Feb-2011, 5:42 PM
I have a Winegard HD-9032 and a Radio Shack Pre-Amp and a generic rotor.

What I'm looking to do is revamp my whole setup from top to bottom to get the best possible reception. I'd like to add a VHF antenna. I'm wondering what they optimum antenna setup would be.

Your UHF antenna is already doing very well. It could be improved by stacking a second HD-9032 above the existing antenna or replacing the single HD-9032 with a pair of XG91 antennas. This article talks about stacking a pair of 4228 antennas, but the theory is valid for any UHF only antenna. http://www.hdtvprimer.com/ANTENNAS/16bay.html

The addition of a high band VHF antenna would be helpful. Consider either a Y10-7-13 or YA1713.

It's possible that a Channel Master 7777 would be slightly better than the Radio Shack amp that you have. There is a switch inside the 7777 that allows you to add the antennas together internally using circuitry in the 7777. To use your existing preamp purchase a UVSJ.

These items can be purchased on-line or perhaps in Worcester at Stark Electronic.

The extra height may not offer much improvement unless it helps you clear nearby trees.

MetHerb
10-Feb-2011, 7:08 PM
Your UHF antenna is already doing very well. It could be improved by stacking a second HD-9032 above the existing antenna or replacing the single HD-9032 with a pair of XG91 antennas.

The addition of a high band VHF antenna would be helpful. Consider either a Y10-7-13 or YA1713.

The extra height may not offer much improvement unless it helps you clear nearby trees.

Thanks for the input. Good to hear that I'm getting good reception as it is. The extra height is to clear some trees and a house a little ways up the street to get Springfield (and potentially Albany) channels better. If I clear that, I have a clear shot since I'm sitting on a hill in the middle of town.

I was looking at a 91XG and placing a YA1713 about 5' below it. Based on my 'radar', there is only one channel below the YA1713's range at channel 6 but I don't think that channel is important enough for me.

I also want to replace the coax so that it is one piece from the preamp power supply inside the house to the preamp on the antenna mast. It is two connected pieces now. What guage coax would you recommend?

I have one other question about the Boston channels I receive. The three channels listed first are WCVB, WBZ then WGBH. Why is WGBH my strongest Boston channel? It takes really clear weather to get WCVB. I also have an LP channel (WRNT- ch. 48) that I can't seem to get at all.

Thanks - Dave

MetHerb
11-Feb-2011, 1:21 PM
Your UHF antenna is already doing very well. It could be improved by stacking a second HD-9032 above the existing antenna or replacing the single HD-9032 with a pair of XG91 antennas. This article talks about stacking a pair of 4228 antennas, but the theory is valid for any UHF only antenna. http://www.hdtvprimer.com/ANTENNAS/16bay.html

The addition of a high band VHF antenna would be helpful. Consider either a Y10-7-13 or YA1713.

The extra height may not offer much improvement unless it helps you clear nearby trees.


Tried posting a reply yesterday, but it did not show up so I'm trying again.

It's good to know that I'm getting good performance, but I'd like to have an "optimum" setup to know that I'm doing all that I can. I'm thinking about replacing the HD9032 with a 91XG and adding a YA1713. I'd connect those through a CM7777.

One other thing that I'd like to do is replace the existing coax with one run from the preamp to the preamp power supply in the house. It's currently two pieces connected outside. I'm wondering guage coax I should use for a 120-150' run?

The extra height I'm considering is to get over a house that's a little higher than my house down the road.

Thanks, Dave

John Candle
11-Feb-2011, 2:08 PM
RG-6 coax is the standard. You can install RG-11 it has less loss then RG-6. The next step up is 'hard line' like the cable company uses from pole to pole or underground.

John Candle
11-Feb-2011, 2:52 PM
With the 91XG and the YA1713 you are pretty much at the end of the rope. Beyond that , you are getting into antenna stacking like stacking like stacking 2 , 8 bay bow tie antennas and quad stacks of YA1713 type antennas and quad stacks of UHF antennas , and the dollar amount goes into a steep climb. There are DX web sites for this sort of thing , Tv and Radio Dxing. DX means D= Distance and X= Unknown. Here are commercial antennas , http://forum.tvfool.com/showthread.php?t=491

MetHerb
11-Feb-2011, 5:59 PM
With the 91XG and the YA1713 you are pretty much at the end of the rope. Beyond that , you are getting into antenna stacking like stacking like stacking 2 , 8 bay bow tie antennas and quad stacks of YA1713 type antennas and quad stacks of UHF antennas , and the dollar amount goes into a steep climb. There are DX web sites for this sort of thing , Tv and Radio Dxing. DX means D= Distance and X= Unknown. Here are commercial antennas , http://forum.tvfool.com/showthread.php?t=491

I think I'll stick with the pair for now and see what I get. I'm thinking that the 91XG will allow me to get a better signal on those that I already get and using a signal line should prevent some loss (at least I would think so). I posted another forum question about the antenna height and maybe playing with that I could get some additional gain as well. I didn't think that lowering and antenna would improve the signal!

Let me ask a hypothetical - what does it take to get a station that a NM of -19? Is that for execptionally clear air where signals travel well? Would I ever be able to get such stations by stacking antennas? At 10', I could make a pole that comes down easily and add antennas as time goes on. I'm thinking that 2 or 4 YA1713's would be my limit. Not sure if I can double up on the 91XG's and have them both pointed in the same direction or not.

Thanks again for the advice!

Dave

Tower Guy
11-Feb-2011, 6:43 PM
Let me ask a hypothetical - what does it take to get a station that a NM of -19?


Theoretically, an antenna with a gain of 22 db and a preamp with a noise figure of 2 db; preamp gain of 23 db or more, and coax plus splitter losses of 6 db or less. This calculation allows for a receiver noise figure of up to 7 db.

Such antennas are impractical, but if you can eek out 6 db of ground gain it's not as bad. Even then, expect frequent dropouts.

MetHerb
11-Feb-2011, 8:20 PM
Theoretically, an antenna with a gain of 22 db and a preamp with a noise figure of 2 db; preamp gain of 23 db or more, and coax plus splitter losses of 6 db or less. This calculation allows for a receiver noise figure of up to 7 db.

Interesting. I can see from the equipment that I will have that the only thing I would not have is an antenna with a gain of 22 db.

Let me ask the question another way, with a UHF antenna with a gain of 16.7 db (the 91XG) and a preamp gain of 26 db and coax and splitter losses of 6 db or less, what would be the "weakest" signal that I could expect under ideal conditions? -15 NM?

What about the same setup with a VHF antenna with a gain of approx. 10 db?

Thanks again!

Tower Guy
11-Feb-2011, 9:47 PM
Let me ask the question another way, with a UHF antenna with a gain of 16.7 db (the 91XG) and a preamp gain of 26 db and coax and splitter losses of 6 db or less, what would be the "weakest" signal that I could expect under ideal conditions? -15 NM?

What about the same setup with a VHF antenna with a gain of approx. 10 db?

Thanks again!

On UHF the tvfool NM level that works with that set-up would vary between -6 db and -22 db. The wide variation occurs because of the way that the receive antenna interacts with the surroundings, plus transmit power variables that occur due to antenna pattern scalloping. However, the likelihood that you'd stumble on the optimum antenna location and height for -22 db NM reception is small.

On VHF with 10 db antenna gain the variation would be between -2 db and -18 db.

There is a ray tracing program called HFTA that can be used to determine what heights are more likely to work well. While intended for frequencies below channel 2 I've used the DOS based predecessor to HFTA (YT) for antenna height calculations for both VHF and UHF TV. The key is to find a height where the main lobe is aimed at the horizon. Other than height, the biggest variable is the slope in front of the antenna.

MetHerb
17-Jul-2012, 7:40 PM
It's been a little over a year since I opened this thread and I've been doing a lot of research on the best value in equipment without going too overboard and I'm getting ready to "pull the trigger" and order what I need.

Before I do, I want to make sure that there aren't any other "tweaks" that I could make from the experts here.

Here's an updated radar plot:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d990081e212f92d

Based on my research, I'm going to go with a 42' guy-wired mast about 35' closer to my house with a rotar and mast that has an Antennas Direct 91XG on top and a Winegard YA-1713 5' below that or just above the rotar. That should put my UHF antenna at 47'.

I'm also going to use a Kitz Tech KT-200-COAX pre-amplifier to minimize noise.

I plan on using RG11 to connect everything with only one splitter to combine the UHF & VHF antenna's to the pre-amp. The total length from antenna to my receiver should be about 100'.

Based on that, I should have a 9db signal reaching my pre-amp, correct? The KT-200-COAX has a 24db gain with <1db in noise. I figure then that I should have a 32db signal reaching my receiver so I'm hoping that I might be able to pull in all of my target stations (down to -15db) and perhaps some of the other ones down to -20 as a bonus from time to time.

Am I being realistic and are there any other ways that I can "tighten" up my system to maximum gain?

Dave

teleview
17-Jul-2012, 8:03 PM
Here is an option , http://www.palcoelectronics.com/pe300.aspx.

Light Weight Aluminum Lay Over Tower that uses no guy wires. Tv antenna mounting and adjustments are done standing on the ground.

GroundUrMast
17-Jul-2012, 8:25 PM
Take a look at these examples of how to use the data in your TV Fool report: http://forum.tvfool.com/showthread.php?t=109

The equipment you've spec'd is at the top of the list of high-gain, low noise & low loss respectively.

Bear in mind that in addition to signal strength (measured as total power delivered to the tuner), you need to take into account interference from stations on the same frequency and adjacent channels.

As an example... When I run the numbers for WCTX, real CH-39 (with some assumptions) I get a net NM of 15.2 dB (a descent fade margin). But you also need to consider the interference from WSBK on the same channel and WGGB on real CH-40. WSBK is about 16 dB lower in level and roughly in the opposite direction. The relatively high front to back ratio of the 91XG should keep enough of the WSBK signal out to allow reception of the WCTX signal. The stronger signal from WGGB is well off to the side, so you are still in fair shape. You won't know for sure until you point the antenna for real. (attached screen shot)

The bottom line is, you've got some of the best directional antennas on your list. These are going to give you the ability to maximize reception of the station you're aiming at while receiving less of the signals to side or rear. To beat this would require custom built antenna arrays.

It's time to hang some metal in the air. :)

Billiam
18-Jul-2012, 2:11 AM
Go with the Antennacraft Y10-7-13 instead of the Winegard Y1713. I set up both on the same mast at the same spot and the Antennacraft was able to get a lock on a very weak Ch. 7 while the Winegard could not. Someone actually modeled these antennas on another board and his spectrum analyzer photos showed the Antennacraft antenna has a solid 2 db higher gain across the entire VHF hi spectrum. Bottom line. If you need more gain then go with the Antennacraft antenna.

GroundUrMast
18-Jul-2012, 2:22 AM
Go with the Antennacraft Y10-7-13 instead of the Winegard Y1713. I set up both on the same mast at the same spot and the Antennacraft was able to get a lock on a very weak Ch. 7 while the Winegard could not. Someone actually modeled these antennas on another board and his spectrum analyzer photos showed the Antennacraft antenna has a solid 2 db higher gain across the entire VHF hi spectrum. Bottom line. If you need more gain then go with the Antennacraft antenna.

And another possible reason to consider the Antennacraft is, it has a balanced 300Ω output (no integral matching transformer / balun) which makes it a better candidate for use in a low loss stacking arrangement where 450Ω open wire or ladder line is used as the phasing harness. Something one may consider doing if getting deep into the DXing hobby or if trying to make a difficult signal more reliable. http://forum.tvfool.com/showthread.php?t=1024

No static at all
18-Jul-2012, 12:27 PM
Go with the Antennacraft Y10-7-13 instead of the Winegard Y1713.I agree. I have found that the Antennacraft Y10-7-13 outperforms the Winegard YA-1713 in real world situations as well.

Billiam
18-Jul-2012, 12:31 PM
Yep. He may actually be able to watch WPRI in Providence with the Y10-7-13.

MetHerb
20-Jul-2012, 8:31 PM
I agree. I have found that the Antennacraft Y10-7-13 outperforms the Winegard YA-1713 in real world situations as well.

I like the fact that the Antennacraft is actually cheaper...thanks for the tip!

Yep. He may actually be able to watch WPRI in Providence with the Y10-7-13.

I'm curious why you say "actually be able to watch WPRI". The TV Fool report list the db at 4.1 and regularly can get stations now the -4 range and as low as -14. My new setup should have an antenna with higher gain (actually, I don't even have a VHF antenna now) and shorter and better cabling for less signal loss. Do VHF signals work differently? My only distant VHF station that I'm hoping to pickup is WRGB from Albany which is listed at 1.5.

Also, I wanted to ask about a low noise spliter/combiner. What does everyone recommend? I have a couple of ideas but I'm just wondering.

Thanks again everyone for your thoughts as I put everything together!

No static at all
20-Jul-2012, 9:16 PM
I would personally use a pre-amp like the Winegard 2870 with separate inputs instead of using a combiner. You will never get back the 1/2 to 1 db gain lost with a UVSJ antenna combiner. Not sure if the low noise figure of the Kitztech amp will make much difference at the end of the day, so maybe others can comment.

GroundUrMast
20-Jul-2012, 9:55 PM
You are certainly approaching, if not already in the area of diminishing returns.

If the goal is optimize to the 'nth' degree, then equip each antenna with a dedicated preamp. Combine downstream of the preamps thus avoiding the NM hit due to the insertion loss of the combiner.

Only if I had a marginal signal that I wanted to make more stable would I consider spending time and money on such a plan.

GroundUrMast
20-Jul-2012, 10:18 PM
...
I'm curious why you say "actually be able to watch WPRI". The TV Fool report list the db at 4.1 and regularly can get stations now the -4 range and as low as -14. My new setup should have an antenna with higher gain (actually, I don't even have a VHF antenna now) and shorter and better cabling for less signal loss. Do VHF signals work differently? My only distant VHF station that I'm hoping to pickup is WRGB from Albany which is listed at 1.5.
...



You've got at least two TV Fool reports posted, so it's not clear which one is most representative of your situation.

Using the NM value of 4.1 dB for WPRI I get an estimated net NM of just under 10 dB at the TV, see attachment.

WRGB on real channel 6 is lower in level (using your NM value of 1.5 dB) and there will quite likely be more RF noise and interference to contend with at that frequency range. Finally, neither the 91XG or Y10713 are designed to receive real channels 2 through 6. Using a Winegard HD5030 to estimate the results I get an estimated net NM of -6.5 dB, see attached.

A net NM of less than 0 dB strongly suggests that you can't expect the tuner to lock on the signal. IMO, a net NM of 10 dB or greater is a reasonable goal when designing for 'reliable' reception.

GroundUrMast
20-Jul-2012, 10:44 PM
Also, I wanted to ask about a low noise spliter/combiner. What does everyone recommend? I have a couple of ideas but I'm just wondering.

Splitters are passive components. They don't produce noise beyond the low level thermal noise. http://en.wikipedia.org/wiki/Johnson%E2%80%93Nyquist_noise

The gain of the preamp is going to elevate the signals well above the noise of any passive component.

Ideal brand splitters from Home Depot have served me well. Others recommend Holland brand.

A splitter with 5 to 1000 MHz of bandwidth and 3.5 dB (2-way), 7 dB (4-way), 10 dB (8-way) insertion loss is representative of the specification ideal for OTA use.

GroundUrMast
21-Jul-2012, 12:16 AM
In the first post of this thread, you expressed a desire to receive WSBK. Are you willing to custom build a very large antenna dedicated to that task? http://forum.tvfool.com/showpost.php?p=14240&postcount=3

Realistically, signals that weak and subject to co-channel and adjacent channel interference are unlikely to be reliable. But some folks have fun chasing after them anyway.

Billiam
21-Jul-2012, 2:11 AM
I like the fact that the Antennacraft is actually cheaper...thanks for the tip!



I'm curious why you say "actually be able to watch WPRI". The TV Fool report list the db at 4.1 and regularly can get stations now the -4 range and as low as -14. My new setup should have an antenna with higher gain (actually, I don't even have a VHF antenna now) and shorter and better cabling for less signal loss. Do VHF signals work differently? My only distant VHF station that I'm hoping to pickup is WRGB from Albany which is listed at 1.5.

Also, I wanted to ask about a low noise spliter/combiner. What does everyone recommend? I have a couple of ideas but I'm just wondering.

Thanks again everyone for your thoughts as I put everything together!

If you are in Stafford Springs then you have a lot of large hills and forests between you and the tower. And I think this is a 2 edge signal. VHF signals are tougher to catch when they are weak compared to UHF signals.

In my current location I have a Ch. 7 with a NM of around 1.0 and it is also a 2 edge. I also have to receive it through several small hills and lots of trees. And I need a pre amp to even see it for a few hours during the day because I have a very large Oak tree in an adjacent yard that directly blocks the path of the signal to my antenna at its current location. But if I moved the antenna to the middle of the roof where a chimney sits, then I would be able to watch it continuously if I added a little more height than its present 22 feet above ground.

I suspect you will run into a similar problem at your location. Every bit of extra gain will count. I've tried several VHF antennas at this location and to date the best one at getting this signal is the Antennacraft HBU 55. I tried the HD Stacker, YA 1713 from Winegard, Y10-7-13 from Antennacraft and 7084p from Winegard in this very spot and NONE of this could even detect a signal on CH. 7 at any time during the day or night while I tested them out. But the HBU 55 is actually able to at least receive it during some night time hours and early morning around daylight and beyond for a couple of hours past sunrise before it fades. BTW. The HBU 55 has about .5 db more gain on Ch. 7 than the Y10-7-13 according to the Antennacraft Tech Support desk. And the UHF section on this antenna is better than expected. It actually outperforms the MXU 59 and 91XG from Antennas Direct on most of the middle range UHF signals at my location. And on the following 2 edge, weak signals, the HBU 55 is slightly weaker on Ch. 45 (NM of minus 12) and also Ch. 17 (NM of minus 8 but comes in sporadically) but stronger on Ch. 15 (NM of around 9) . Overall it gets the nod over the other two UHF only antennas.

Billiam
21-Jul-2012, 2:16 AM
I should add. I swapped out my RG6 for RG11 (100 foot run) and even though I am using a Pre amp (8275 from Winegard) I saw a 1.5 to 2 db gain across all channels. Whoever claims you don't need both for improving the strength of a weak signal is uninformed. It worked for me. If you see some signals breaking up after you install your new antenna or antennas and believe that another db or two will stabilize the picture, then I recommend trying RG 11 in place of RG 6 cable.

teleview
21-Jul-2012, 2:55 AM
I agree with Billiam. On the issue of using RG-11 coax.

Reception situations that require squeezing more of signal strength out , 2 to 4 dB more signal. RG-11 has less loss then RG-6.

RG-11 coax is good to use.

Here are Ultra low noise amplifiers that will squeeze out a few more dB of cleaner signal.

http://www.kitztech.com

http://www.researchcomms.com/hdtv.html