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-   -   LNA 200 Tech Test (http://forum.tvfool.com/showthread.php?t=13583)

ADTech 26-Aug-2013 3:58 PM

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

GroundUrMast 26-Aug-2013 5:17 PM

Thank you. Now I feel bad for having suggested the LNA-200 recently.:o

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...

ADTech 26-Aug-2013 8:29 PM

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.

GroundUrMast 26-Aug-2013 11:22 PM

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.

Pete Higgins 30-Aug-2013 2:55 AM

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?

pointer 21-Aug-2014 7:37 PM

Quote:

Originally Posted by GroundUrMast (Post 37924)
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.

Jason l 8-Apr-2015 11:48 AM

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

WIRELESS ENGINEER 26-Jan-2017 8:55 PM

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


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