HiLetgo 0.1-2000MHz RF WideBand Amplifier 30dB High Gain Low Noise LNA Amplifier

This amplifier is perfect for increasing the reception of an RTL-SDR dongle. It just about covers its entire tuning range, and then some. I've mainly been using it for shortwave where it has dramatically increased the number of channels received. It's also proven itself well on FM (just don't overdrive the SDR frontend!) and other bands.Just one caveat: you'll need to BYOP (Bring Your Own Power) as its DC-blocking capacitors prevent it getting power from the coax. A nine-volt battery should do the trick however. Interestingly enough though, the amplifier ("N02" INA-02186 perhaps?) is designed to take bias-T power on its output pin (7V max), meaning that those adventurous enough to make some slight modifications might just be able to power the amplifier straight from the RTL-SDR!As mentioned before, this amplifier performs quite well and can in fact attain its advertised +30dB gain. However, do note that, like any other LNA, it will amplify the noise floor somewhat as well.In summary, this amplifier is ideal for anyone wanting an inexpensive upgrade for their RTL-SDR.

This preamp works fine, but I think you have to apply it correctly. It's a GaAs Rf amplifier chip, similar to unit such as the Avago 82563, but not that -- possibly a Chinese clone or variant of a different chip. This one appears to run with a current of about 35 ma to deliver its full gain, and is intended for 5V operation. The sellers have adapted it to run at 9-12 volts by adding the 220 ohm resistor, to drop the voltage down. If the voltage is reduced too much, its gain goes down. In fact, this is a good way to make a variable gain preamp - by driving it with different voltages (without a dropping resistor), say between 3V and 5V. At the lowest voltages, it actually becomes an attenuator. Of course, the current consumption is fairly high for that application -- you might do better in your attenuator circuit by just using a PIN diode. The 220 ohm resistor permits full output when connected to 12V, but at 9V the gain will be much less, which may be why some reviewing it here have had mediocre results with it. If you intend to use it at 9V, you best reduce the resistance. In my application, using two Lithium Ion batteries (3.2-4.2V each) I found a good choice was to change the 220 ohm resistor to 120 ohms. However in my circuit, I also added a 1 mH choke as shown, which has 33 ohms series resistance, so my resistor is actually 100 ohms. The lower the voltage you run it from, the more the inductor is necessary for best output. Check that it is drawing at least 25-35 ma. Also note that it's good to mount the unit in a grounded metal box. Traditionally, the hobbyist mounts these kinds of devices inside an Altoids tin. In my case I used some copper tape lining inside a plastic box. The seller has stripped down their product here to the bare minimum, and I think they could have done a better job making it usable over a wider voltage range. But with care, it will give excellent results. I have two cautions. First, don't try to run this from 5V -- unless you make the modification I suggest (small resistor + RF choke). Second, be careful soldering around this, because GaAs circuits die very easily when treated roughly. If you're not comfortable making changes to the circuit, perhaps it would be better to get one of the other units. Or, get a transistor-based (Jfet) preamp. Those would be more costly, though. Only the very low cost justifies this circuit.

Bought it thinking thinking at this price if it don't work no big deal. Wow!! did it ever work.. In combo with a DIY long wire antenna Full bars on stations I couldn't hear and still can't without it.Great product.

I am usually skeptical of negative reviews but I had high hopes for this amplifier even though my optimism was not deserved. I needed a small preamp for a shortwave receiver I am building. I have already built my own preamplifier but I wanted to purchase a commercial one to compare my homebrew one against. I soldered power wires onto the board and hooked it up to my oscilloscope and tracking generator and swept from 0 to 30 MHz. The Bode plot showed no appreciable gain across the spectrum. I get the same response from the amplifier whether power was applied or not. Looking at the power output of my lab grade power supply, it showed it was consuming 0.00 watts. It should show even a small amount of power being consumed. The power supply can show the power usage all the way down to a 100th of a watt. Seeing no power being used was a very bad sign. Next I pulled out my magnifying glasses and started probing around on the board. There are a total of 6 components on the board (excluding the SMA connectors). When I touched the IC in the middle, it wiggled. I inspected it further and saw that the right hand side was not soldered to the board. I pulled out my soldering iron and reflowed solder on all the ICs pins and the other 5 components as well. I really thought that was going to fix it but nope, still no gain. It is possible that I just got a bad one and maybe others will have better luck, but I am a little disappointed to say the least. I don't even feel like dealing with the hassle of trying to return it. I will just accept the loss and see it as a fun little $10 experiment on a Saturday morning.

I bought this amp to boost the signal level from my small receiving loop antenna for Amateur Radio. I use that antenna as a noise source for my MFJ 1026 Noise Cancellation unit. I had a 10 dB preamp on there before, and it just didn't provide enough noise for the MFJ to work effectively. With this unit, I can amplify the noise to the point where it's even louder than the main antenna, even with the built-in preamp in the MFJ turned off. The MFJ now cancels all of the noise from my immediate neighbor's house almost totally. I am powering the from an old 6VDC wall wart that puts out 9V with this minimal load. This is probably the best $10 I ever spent.

Used this inline with a FM band pass filter and RTL-SDR to receive NOAA satellite apt signals. Seems to help. Wired a 9v battery to it. Read a bunch of the way more in-depth reviews and figured for 15$ it was with a try. Not 100% sure this is making a big difference for what I’m trying to do but it’s not making it worse, so there’s that.

Cleans up background thanks guys