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Old 10-Sep-2013, 12:51 AM   #1
Pete Higgins
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Join Date: Apr 2013
Location: California, 58 miles @112 degrees from Mt. Wilson
Posts: 83
Winegard LNA-200 BoostXT Outdoor Ultra Low Noise Preamplifier

Winegard advertises their LNA-200 mast mounted preamplifier with some pretty impressive specifications : VHF (Low) Gain: 20 dB, VHF (High) Gain: 15 dB
Power Out (P1db): +15 dBm
Output IP3: +25 dBm
VHF Noise Figure: 3.0 dB

UHF Gain 18 dB
Power Out (P1db): +18.4 dBm
Output IP3: +35.5 dBm
UHF Noise Figure 1.0 dB

They also list its “Maximum Total Input (microvolts)” as “2,024,789”.


Since I have one local FM station on 99.9 MHz @ -13.4 dBm and a local TV station on RF channel 26 (24.1- .4) @ -15.6 dBm that overloads both my Winegard AP-2870 and HDP-269 models I had hoped this new amplifier would live up to its promise –so I bought one. Unfortunately, it didn’t!

I received my new Winegard LNA-200 late Wednesday afternoon (4 Sep 2013). Thursday morning I started to test it. I have a Solid Signal HDB-8X fix mounted on a pushup mast pointed towards Los Angeles. I was using just the UHF portion of an RCA TVPRAMP-1R (#2) configured for separate UHF/VHF inputs and the FM trap selected with the HDB-8X. I have a dedicated RG-6 run from the HDB-8X to a coax switch in my garage. Since it required the least amount of climbing to get at and only took swapping two cables I substituted the new Winegard LNA-200 for the HDB-8X’s RCA TVPRAMP-1R.

Before I took the RCA out of line I ran through the LA channels to verify everything was working. Then I swapped out the power supplies, went up on the roof and swapped out the amps, returned to the garage to power the Winegard and came in to check reception.

The new Winegard appeared to be working except KTLA RF channel 31 (5.1-.3) was missing. Since Winegard advertises this amp to withstand a “Maximum Total Input (microvolts)” of 2,024,789 ÁV which in a 75 ohm system, I believe, should be a signal level of about +17.38 dBm I wasn’t expecting this. Interesting! Both because the HDB8X shouldn’t have much response to the FM signal and the one strong TV station is almost 33 dBm below the advertised “Maximum Total Input (microvolts)”.

Above the HDB8X, I have a Radio Shack 15-1220 rotor turning a Channel Master CM-4228 and a Winegard YA-1713 High VHF antenna. I usually leave those antennas pointed towards the San Diego stations. I was also using an RCA TVPRAMP-1R (#2) configured for separate UHF/VHF inputs and the FM trap selected with that array. I decided to try the Winegard LNA-200 with the VHF/UHF array. I reconnected the HDB8X to its original RCA (#3). Since the LNA-200 only has one input I disconnected the separate VHF & UHF cables from the array RCA amp and connected them through a UVSJ. The output of the UVSJ went to the LNA-200 input and the LNA-200 output went through a separate RG-6 cable to the power inserter in the garage. I now had the HDB-8X/RCA’s power inserter and the CM-4228/YA-1713/LNA-200’s power inserter feeding opposite sides of the coax switch. The first difference I noted, when I substituted the UVSJ and the LNA-200 for the RCA, channel 26 was coming in with a very watchable SNR of ~18.5. With the RCA amp and the array pointed towards San Diego I don’t receive my local RF channel 26 at all. I am guessing this is due to the signal ingress issue ADTech reported on.

I rotated the array towards LA. As expected, RF channel 26’s SNR jumped to 30. That’s the highest my tuner cards register. When I tried RF channel 31 it was still gone! I went out in the garage and switched to the HDB8X/RCA and channel 31 popped back in with an SNR of 24.7.

Removed from its plastic case, the circuit board measures 3 15\32” X 1 5/8”. The 1 5/8” grows to 2 5/16” if you measure to the ends of the ‘F’ connectors.

Front


Back


It appears to have three active amplifiers (Q1-Q3)
Closeup


In all fairness, I’m reporting on one LNA-200 sample, tested at my unique location. I’m sure it is a good product that would work well for many people. It didn’t show the pronounced overload I experienced with my AP-2870 and to a lesser degree my HDP-269 but in spite of its advertised overload specifications it none the less appeared to be overloading. Additionally, unlike the RCA’s that at least have a metal plate shielding their circuitry, the LNA-200 is completely housed in a plastic case. I’m pretty sure it’s this lack of shielding that allowed local signal ingress when the antenna was pointed 125 deg. away from the received signal.

On the channels that both amplifiers receive clearly, it looked like the LNA-200 might have a few tenths of a dB SNR advantage over the RCA’s, but keep in mind I was comparing the $23.00 RCA’s, connected to a lower fixed mounted antenna, to the CM-4228/LNA-200 mounted 10’ higher, that I can peak for best SNR with a rotor.


When ADTech tested his sample he found: “On the LNA200, I measured an average of 4.7 dB NF on low-V, 5.6 dB on high-V, and 2.8 dB on UHF as computed by the NF meter software. Major spikes from ingress were evident, some as much as 8 dB.” His test results seem to correlate with the performance I experienced.
Attached Images
File Type: jpg LNA-200 Input Power.JPG (36.3 KB, 8122 views)
File Type: jpg LNA-200 Ckt Board Front 2.JPG (250.2 KB, 9089 views)
File Type: jpg LNA-200 Ckt Board Closeup.JPG (26.7 KB, 8157 views)
File Type: jpg LNA-200 Ckt Board Back 2.JPG (123.9 KB, 7976 views)

Last edited by Pete Higgins; 10-Sep-2013 at 12:55 AM.
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