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Old 26-Aug-2013, 4:58 PM   #1
ADTech
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LNA 200 Tech Test

Reality check time.

I posted some data over at AVS a few days back. Other posters also highlighted the obviously incorrect marketing data in preceding posts.

http://www.avsforum.com/t/381623/the...#post_23632553

http://www.avsforum.com/t/381623/the...#post_23636098
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Old 26-Aug-2013, 6:17 PM   #2
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Thank you. Now I feel bad for having suggested the LNA-200 recently.

Any news on a replacement for the CPA-19? Last time we spoke it sounded as if it was in the works, but preliminary stages at best...
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Old 26-Aug-2013, 9:29 PM   #3
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Look, the LNA isn't a "bad" pre-amp, it's actually a somewhat decent one with several limitations. It just simply isn't anywhere near as good as claimed.

* VHF noise figure is poor.
* UHF noise figure is fair, averaging in the 2 db range, which is better than any previous Winegard I've tested by 1-4 dB.
* Marketing claims of overload tolerance are preposterous.
* Technical specs for overload appear to be "generous".
* Stray Signal Ingress

If they put it in a metal box to eliminate ingress, and cleaned up the internal filters to reduce the obvious signal attenuation (and bought a new noise figure meter), it would be a pretty good amp.

The new pre-amp is still plodding along. I don't know what is characteristics are going to be as we've gotten multiple iterations of prototypes. The most recent samples went straight to the contract engineers due to time constraints so I haven't seen them.
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Last edited by ADTech; 26-Aug-2013 at 9:40 PM.
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Old 27-Aug-2013, 12:22 AM   #4
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I presume the ingress issue could be dealt with by enclosing the mast head unit in an RF tight enclosure. That would add $10 to $20 worth of hardware though.

Given the pleasantly positive review of the RCA preamp, It's hard to justify starting with an amplifier that costs more and lacks the separate UHF/VHF inputs.
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Old 30-Aug-2013, 3:55 AM   #5
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ADTech & All,

For what itís worth, I bought one of the Winegard LNA-200ís from Solid Signal for $32.99 + $5.95 shipping with promo code AMP25 Ėjust to try. It is scheduled to be delivered on Wednesday August 4th.


I have a -13.4 dBm FM signal and a -15.6 dBm TV signal both of which overload my Winegard AP-2870 and HDP-269.

Thanks to ADTech, I also have 4 of the RCA TVPRAMP1R amplifiers that donít show any signs of overload and work better than anything else Iíve tried.

When I get the new LNA-200, Iíll substitute it for one of the RCAís to see if it overloads at my location. Provided it isnít 100 deg. out Iíll try to run a comparison test to see if it improves my SNRís.

ADTech,

Congratulations. Does your boss expect the community to chip in for the new equipment?
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Old 21-Aug-2014, 8:37 PM   #6
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Quote:
Originally Posted by GroundUrMast View Post
I presume the ingress issue could be dealt with by enclosing the mast head unit in an RF tight enclosure. That would add $10 to $20 worth of hardware though.

Given the pleasantly positive review of the RCA preamp, It's hard to justify starting with an amplifier that costs more and lacks the separate UHF/VHF inputs.
Instead of a metal box, I have found that wrapping a module with metal foil tape was inexpensive shielded more effectively. This was deep inside some old computer equipment with strong digital interference. Some tape is made with conductive adhesive, but that's really not necessary as long as the tape is one continuous piece, overlapped where necessary. My tape was 2" wide copper, but wider or narrower would do. I soldered it to the module's ground pin directly. On a mast, the tape could be extended to the cable's coax shield with a large overlap. Capacitive coupling dominates at high frequencies.
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Old 8-Apr-2015, 12:48 PM   #7
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I purchased this Lna-200 because I had great success with their 8275 that is no longer available. It basically didn't inprove any of my channels I actually lost channels compared to the old high gain preamps they sold. For me I use a high gain preamp to get channels over 70 miles away with the high gain amp I get the channels without the high gain 8275 I just don't get the channels. With a 25 foot cable hook to my antenna straight no amp I am down nine channels if I hook up the high gain Winegard I get nine more channels.when I hoped up the boost 200 it was basically just like running a straight cable to my antenna without amp. I contacted Winegard I sent the amp back two days after I purchased it and ask Winegard why they are pushing this one single preamp that doesn't work
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Old 26-Jan-2017, 9:55 PM   #8
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Very little has changed in TV reception technology in the past 50 years.

What HAS changed is slick marketing

Since both the noise floor present and the noise figure of the average TV tuner is far above that of most preamps, I challenge anybody to see the difference in the reception.

And the "overload" figures are also very deceptive these days.

My winegard ap-8700 was rated at 93000 microvolts on UHF and 105 microvolts on vhf and it was a better amp than the LNA 200 and had a 2.8 db noise figure

Long held standards for the amount of gain a particular antenna design produces is also out the window these days.

With gain figures using a theoretical non existent reference
Becoming the norm.

All done to make THEIR product APPEAR to be better than the other guy

Its done because it works

Today's consumers believe anything they see on YouTube and as seen on TV hucksters

Last edited by WIRELESS ENGINEER; 7-Feb-2017 at 4:11 AM.
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Old 12-Apr-2019, 1:34 PM   #9
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LNA 200. Let's get this thread going again!

Quote:
Originally Posted by Pete Higgins View Post
ADTech & All,

For what itís worth, I bought one of the Winegard LNA-200ís from Solid Signal for $32.99 + $5.95 shipping with promo code AMP25 Ėjust to try. It is scheduled to be delivered on Wednesday August 4th.


I have a -13.4 dBm FM signal and a -15.6 dBm TV signal both of which overload my Winegard AP-2870 and HDP-269.

Thanks to ADTech, I also have 4 of the RCA TVPRAMP1R amplifiers that donít show any signs of overload and work better than anything else Iíve tried.

When I get the new LNA-200, Iíll substitute it for one of the RCAís to see if it overloads at my location. Provided it isnít 100 deg. out Iíll try to run a comparison test to see if it improves my SNRís.

ADTech,

Congratulations. Does your boss expect the community to chip in for the new equipment?
Hi all, I was just wondering whatever happened with this thread?, It just seemed to die off. AD Tech offered some real world testing results and his opinion, which we value here.

Pete Higgins is a enthusiast, and I know he must have done the testing that he was planning to do. I'm just wondering how it turned out?

Also, has anybody else to used this Winegard LNA 200 ?

I am presently using a LNA 200, but plan to do some testing. I want to get a Kitz Tech pre-amp and see if it will add to my signal strength, what I read it would be helpful addition to my set up I am working on right now.
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Old 12-Apr-2019, 3:43 PM   #10
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Quote:
Originally Posted by bobsgarage View Post
Hi all, I was just wondering whatever happened with this thread?, It just seemed to die off. AD Tech offered some real world testing results and his opinion, which we value here.

Pete Higgins is a enthusiast, and I know he must have done the testing that he was planning to do. I'm just wondering how it turned out?
Pete Higgins gave a report of his LNA200 tests on another forum. He wasn't any more impressed with its performance than ADTech was: it's an OK preamp, but not as good as Winegard says it is.
https://www.highdefforum.com/local-h...amplifier.html
Quote:
I am presently using a LNA 200, but plan to do some testing. I want to get a Kitz Tech pre-amp and see if it will add to my signal strength, what I read it would be helpful addition to my set up I am working on right now.
The Kitztech KT-200 has a low noise figure that might improve the reception of weak signals, but it is not likely to make your signals stronger. If you buy it, get the KT-200 with the outdoor enclosure.

Quote:
Also, has anybody else to used this Winegard LNA 200 ?
I am planning to make some tests, if I have the time. My concern is about the voltage to the preamp since it uses a 5V power supply. A long coax run might cause the voltage to drop too low for proper operation.

I tested the CM7777HD for voltage drop. It can go as low as 4V measured at the preamp. I don't like the enclosure for the 7777HD; it doesn't seem like a good design for outdoor use. I use it indoors as an instrumentation amp for testing.
https://www.highdefforum.com/1410662-post23.html
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Last edited by rabbit73; 12-Apr-2019 at 4:01 PM.
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Old 12-Apr-2019, 5:56 PM   #11
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Ok channel master&johansson amp

Quote:
Originally Posted by rabbit73 View Post
Pete Higgins gave a report of his LNA200 tests on another forum. He wasn't any more impressed with its performance than ADTech was: it's an OK preamp, but not as good as Winegard says it is.
https://www.highdefforum.com/local-h...amplifier.html

The Kitztech KT-200 has a low noise figure that might improve the reception of weak signals, but it is not likely to make your signals stronger. If you buy it, get the KT-200 with the outdoor enclosure.

I am planning to make some tests, if I have the time. My concern is about the voltage to the preamp since it uses a 5V power supply. A long coax run might cause the voltage to drop too low for proper operation.

I tested the CM7777HD for voltage drop. It can go as low as 4V measured at the preamp. I don't like the enclosure for the 7777HD; it doesn't seem like a good design for outdoor use. I use it indoors as an instrumentation amp for testing.
https://www.highdefforum.com/1410662-post23.html
With the channel master amp/the Johansson amp kit 24 volts.With it's uhf/vh f
Witch one of those amp's tested too WIN the best AMP too use or is it the hi price blonder toung AMP ??
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Old 13-Apr-2019, 1:16 PM   #12
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K T 200 Vs. L N A 200

Quote:
Originally Posted by rabbit73 View Post
Pete Higgins gave a report of his LNA200 tests on another forum. He wasn't any more impressed with its performance than ADTech was: it's an OK preamp, but not as good as Winegard says.

The Kitztech KT-200 has a low noise figure that might improve the reception of weak signals, but it is not likely to make your signals stronger. If you buy it, get the KT-200 with the outdoor enclosure.

I am planning to make some tests, if I have the time. My concern is about the voltage to the preamp since it uses a 5V power supply. A long coax run might cause the voltage to drop too low for proper operation.

I tested the CM7777HD for voltage drop. It can go as low as 4V measured at the preamp. I don't like the enclosure for the 7777HD; it doesn't seem like a good design for outdoor use. I use it indoors.
Hello Rabbit,

I'm glad I revived this thread. I'm hoping that others can learn from your comments and the original testing. It would also be great to see your updated testing of the LNA 200.

So, how do you test those? Will you be testing for overload and Noise?

You may have seen my posts about the pc-based Spectrum analyzer that Pete Higgins introduced to these groups. I'm wondering if I can use it to compare the LNA 200 to the KT 200?

It doesn't surprise me that Winegard overstated the overload and noise figures. Isn't that the same company who came out with their 7 through 69 series of antennas right after we went to 51 channels? Sorry I couldn't resist that!

When I bought my LNA 200 I wasn't a member of this forum yet, otherwise I probably wouldn't have purchased it. I had seen it on Amazon and Solid signal but my local electronics store had one on the shelf for a surprisingly lower price, I think I paid $30 for it. Impulse Buy!

I actually never used it until recently when I set up my new array and since I had 50 ft of cable I figured I would use it to boost the signal through all the losses of the cable, splitter etcetera.

So, staying on topic, if the KT 200 has .4 DB of noise and LNA-200 is somewhere around 2 to 3 DB of noise, wouldn't that help a little?



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Old 13-Apr-2019, 4:03 PM   #13
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Originally Posted by bobsgarage View Post
It would also be great to see your updated testing of the LNA 200.

So, how do you test those? Will you be testing for overload and Noise?
Measuring the noise figure of a preamp is not easily done; I don't have the proper equipment to do it accurately. It requires an expensive calibrated noise source. I depend upon the measurements done by Calaveras. The attachment is the result of his preamp measurements.

I can get a rough idea by monitoring the SNR of a weak signal. The preamp that gives the higher SNR of a weak signal should have the lowest NF.

Quote:
You may have seen my posts about the pc-based Spectrum analyzer that Pete Higgins introduced to these groups. I'm wondering if I can use it to compare the LNA 200 to the KT 200?
A spectrum analyzer can be used to make an overload test by measuring IP3, Third order intercept point, which is what Calaveras does.

The way I make a preamp overload test is to increase the signal input to the preamp until the SNR of a weak signal starts to fall. This is the point when the IMD products from the stronger signals create spurious signals that raise the noise floor to reduce the SNR of the weak signal.
Quote:
It doesn't surprise me that Winegard overstated the overload and noise figures. Isn't that the same company who came out with their 7 through 69 series of antennas right after we went to 51 channels? Sorry I couldn't resist that!
An antenna manufacturer isn't going redesign an antenna unless they can make a profit doing it.
Quote:
When I bought my LNA 200 I wasn't a member of this forum yet, otherwise I probably wouldn't have purchased it. I had seen it on Amazon and Solid signal but my local electronics store had one on the shelf for a surprisingly lower price, I think I paid $30 for it. Impulse Buy!
It's an OK preamp, but it isn't as good as their marketing description says it is.
Quote:
So, staying on topic, if the KT 200 has .4 DB of noise and LNA-200 is somewhere around 2 to 3 DB of noise, wouldn't that help a little?
A preamp with a lower NF should make a marginal weak signal a little more reliable. The tests by Calaveras say:
Kitztech KT-200 NF
VHF 0.6 dB
UHF 1.2 dB
Winegard LNA200 NF
VHF 5.7 dB
UHF 3.0 dB
Attached Images
File Type: jpg Preamp_Summary3S.jpg (362.3 KB, 190 views)
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Last edited by rabbit73; 13-Apr-2019 at 4:06 PM.
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Old 13-Apr-2019, 7:05 PM   #14
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An extremely low nose figure in a preamp, such as the Kitztech, has very little effect on TV reception. This is because the antenna is aimed at the horizon. Only when an antenna is aimed up at a satellite or celestial body will a noise figure less than 3 dB offer much improvement.

The exception is that a lower nose preamp can be located further from the antenna, after some feed line loss, or after a band pass filter, and still offer an advantage.

https://www.spaceacademy.net.au/spacelink/noise.htm
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Old 13-Apr-2019, 7:08 PM   #15
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Norton blocked that link for me; said it was dangerous......might have been interesting.

OK, I was able to read the Google cache. Extract here:

NOISE TEMPERATURE, NOISE FACTOR and NOISE FIGURE

Noise is ubiquitous in all communication systems. This noise may originate in the receiving system itself, and it is also present throughout the universe. It has a Gaussian or Normal distribution (bell-shaped curve), and can be characterised by a quantity we call the noise temperature Tn, which has the units of absolute temperature (Kelvin).

If the receiver is connected to an antenna that is pointed to the sky then the noise at the output of the receiver is a mixture of noise generated within the receiver itself and the sky noise collected by the antenna and transferred to the input of the receiver.

If the receiver is not connected to an antenna then the noise measured at the receiver output is only due to the noise generated in the receiver itself. This noise is usually referred to the receiver input and this input power is associated with a noise temperature that is called the receiver system temperature Tsys. This temperature is what sets the limiting sensitivity of the receiver. The lower this temperature the better the receiver.

A poor receiver may have a system noise temperature of several thousands of degrees Kelvin. A medium quality receiver may have a system temperature of several hundred Kelvin, and a good receiver a noise temperature below 100 K.

Note that if a communications receiver is pointed to a region of the sky near the galactic centre where the sky noise may be several thousand Kelvin, then there is no point in striving to have a receiver noise temperature below 100 K, because in this case the system noise temperature will be determined by the background sky noise, not the receiver noise.

ENGINEERING NOISE UNITS

Receiving systems that require a very low noise temperature often employ a low noise amplifier (LNA) that is placed very close to the antenna (to avoid cable losses). These amplifiers are characterised by two quantities: their noise performance and their overall gain. Often the internal noise is specified by a noise factor F or a noise figure nf. These are units used by engineers. However, there are simple formulae that relate F, nf and Tn.

The following graph allows easy conversion between noise figure and noise temperature.



SKY NOISE TEMPERATURE

Astronomical radio sources in the sky are a source of noise for receivers with antennae pointing skyward. It is often useful to know the value of the effective sky temperature and how it varies with frequency. The graph below left shows the effective sky temperature for a wide beamwidth antenna.

By far the greatest noise generator in the sky lies at the center of the milky way, and if this lies in the beam of the antenna the noise temperature will be greater than when the galactic center and most of the galactic plane lies below the horizon. The two lines at the extremes of the hatched region indicate the minimum and maximum noise temperatures to be expected for these two extreme conditions. The actual noise temperature experienced will thus lie in the hatched region between these two conditions.



END Extract

Thank you.
Attached Images
File Type: jpg Noise Figure vs Noise Temperature_1.jpg (129.5 KB, 895 views)
File Type: jpg Sky Noise Temperature vs Freq MHz_1.jpg (87.4 KB, 841 views)
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Old 13-Apr-2019, 8:45 PM   #16
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Signal strength vs signal quality

Quote:
Originally Posted by rabbit73 View Post
Measuring the noise figure of a preamp is not easily done; I don't have the proper equipment .I depend upon the measurements done by Calaveras. The attachment is the result of his preamp measurements.

I can get a rough idea by monitoring the SNR of a weak signal. The preamp that gives the higher SNR of a weak signal should have the lowest NF.

(LNA200)
It's an OK preamp, but it isn't as good as their marketing description says it is.
A preamp with a lower NF should make a marginal weak signal a little more reliable. The tests by Calaveras say:
Kitztech KT-200 NF
VHF 0.6 dB
UHF 1.2 dB
Winegard LNA200 NF
VHF 5.7 dB
UHF 3.0 dB
Well, that's quite a big difference (in noise) between those two amps, I might buy the KT 200 just to experiment with.

I do have some issues pulling in some stations. I have to establish a baseline though because I'm looking at these different signal meters at random. I like the signal meter on my Toshiba TVs . They have a couple of different types of information including a graph.

I don't like the signal meter on the Channel Master or the Homeworx tuners. They use signal quality which may or may not be accurate. They use the same software.

At any rate, as you say, if I have a marginal signal that low noise Kitz preamp could help.


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Old 13-Apr-2019, 11:29 PM   #17
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Not all ways.
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Old 16-Apr-2019, 1:08 PM   #18
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Tower guy and Rabbit, thanks!

Tower Guy and Rabbit,

Thanks for the article and explanation about noise and noise in the universe. I'm kind of a space buff,I like to watch My Science Channel other channels, one of my favorite shows is "The Universe".

On one particular show about the Big Bang, they were talking about leftover energy after the big bang.They actually used the static seen on an old analog TV set when there is no signal. As an example they showed the TV screen with that random static said that was energy / noise left over from the Big Bang it's all around us.

Anyhow, the article made for some good reading. I'll probably have to read it and several more times to even get a grasp on it.

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Old 17-Apr-2019, 12:27 PM   #19
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Noise yes if you're antennas installed 10ft up and not over power lines will help with your noise.And the AMP you buy to day helps
Sometimes to keep the noise being out of control.

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