RTL-SDR.COM Wideband Amplifier (Real World Results?)

[Omega-TI]

I've been eyeballing the RTL-SDR wideband amplifier at Amazon (pictured below) << HERE >>. I've been wondering, does anyone here use one? If so, what are your real world results. Does it appreciably elevate the noise floor? Since I live in a rural setting, I'm thinking this may be "just the ticket", but figured it may be wise to inquire with you experts & users here first.

 

[PDXh0b0]

Myself I have the Nooelce Lana , but I am in suburban hell, so it makes more problems than it help. On facebook groups, allot of folks in the rural & islands use them for weather satellite imagery

 

[prcguy]

I don't have one of these amps but I did look up the specs posted below.

• Frequency range of 50 MHz to 4000 MHz
• Noise figure = 0.6dB @ 900 MHz
• OIP3 = 39.5 dBm @ 900 MHz
• P1 Saturation = 22.7 dBm @ 1960 MHz
• Gain = 18.7 dB @ 900 MHz

The specs are not terrible and this amp could work ok for some people connected to a wide band antenna in a low RF environment. For others like myself this amp would fold up and die connected to a wide band antenna due to lots of super strong signals here that would nearly saturate the amp and at the very least create lots of IMD raising the noise floor and creating lots of ghost signals.

This type of amplifier would be best served right at the base of the antenna to make up for feedline loss.

 

[PDXh0b0]

I don't have one of these amps but I did look up the specs posted below.

• Frequency range of 50 MHz to 4000 MHz
• Noise figure = 0.6dB @ 900 MHz
• OIP3 = 39.5 dBm @ 900 MHz
• P1 Saturation = 22.7 dBm @ 1960 MHz
• Gain = 18.7 dB @ 900 MHz

The specs are not terrible and this amp could work ok for some people connected to a wide band antenna in a low RF environment. For others like myself this amp would fold up and die connected to a wide band antenna due to lots of super strong signals here that would nearly saturate the amp and at the very least create lots of IMD raising the noise floor and creating lots of ghost signals.

This type of amplifier would be best served right at the base of the antenna to make up for feedline loss.

Always grateful you are still here

 

[amusement]

Owned wideband LNA for a while. Using SDRSharp I can see an increase of 'floor' noise. Wanted to show the difference between preamplifier and non. Then...well..wideband LNA doesn't work. I've had it for a long time, but it's dead cold. Here's the difference between a dead cold wideband LNA and a RTL-sdr.com v3 without. Sorry I couldn't be any more help. Guess I will be using my very old but, reliable GRE Super Amplifier. edit: Ordered another Wideband LNA from RTL-SDR.com

 

[waynedc]

Owned wideband LNA for a while. Using SDRSharp I can see an increase of 'floor' noise. Wanted to show the difference between preamplifier and non. Then...well..wideband LNA doesn't work. I've had it for a long time, but it's dead cold. Here's the difference between a dead cold wideband LNA and a RTL-sdr.com v3 without. Sorry I couldn't be any more help. Guess I will be using my very old but, reliable GRE Super Amplifier. edit: Ordered another Wideband LNA from RTL-SDR.com

Did you turn on the bias-t?

 

[Omega-TI]

Did you turn on the bias-t?

About this, I'm assuming it's safe to use the bias-t when using the dipole software that comes with the device, correct? Sorry for the super basic question, but I'm assuming (possibly in error) that it's not a "shorted" antenna like a J-Pole. I think I read somewhere that there could be damaging results if used on the wrong type of antenna.

 

[waynedc]

About this, I'm assuming it's safe to use the bias-t when using the dipole software that comes with the device, correct? Sorry for the super basic question, but I'm assuming (possibly in error) that it's not a "shorted" antenna like a J-Pole. I think I read somewhere that there could be damaging results if used on the wrong type of antenna.

Probably best to use a DC-Block between the LNA and the antenna just in case if you are unsure.

 

[Omega-TI]

Probably best to use a DC-Block between the LNA and the antenna just in case if you are unsure.

Do you have a link to a "GOOD" SMA version? I see numerous ones on Amazon, but don't want to end up with junk. Thanks.

 

[a417]

Do you have a link to a "GOOD" SMA version? I see numerous ones on Amazon, but don't want to end up with junk. Thanks.

Limiting your selection to SMA might leave you in that cheap chinesium range which might sour your taste.

If you decide to not make the connector the limiting factor, there are many more widely known brands (Stridberg, etc) that use different connectors. A simple jumper to SMA from whatever the LNA uses (BNC, N Type...) can accomplish your SMA needs at the last possible connection point.

 

[waynedc]

Do you have a link to a "GOOD" SMA version? I see numerous ones on Amazon, but don't want to end up with junk. Thanks.

I use this one:

https://www.nooelec.com/store/sdr/sdr-addons/attenuators/dc-block.html

 

[Omega-TI]

I use this one:

https://www.nooelec.com/store/sdr/sdr-addons/attenuators/dc-block.html

THANKS! I've saved that link and will order it at the same time I order an LNA. It's adding up fast.

 

[Omega-TI]

Limiting your selection to SMA might leave you in that cheap chinesium range which might sour your taste.

If you decide to not make the connector the limiting factor, there are many more widely known brands (Stridberg, etc) that use different connectors. A simple jumper to SMA from whatever the LNA uses (BNC, N Type...) can accomplish your SMA needs at the last possible connection point.

Thanks, but I'm going to have to take my chances. I've spent as much over the past couple of weeks on adapters, gender changers and cabling as I did on the dongle. I don't want to add any more adapters into the mix, but I think I financially committed myself to SMA already. If this was a primary hobby setup, it would be a different story.

 

[waynedc]

THANKS! I've saved that link and will order it at the same time I order an LNA. It's adding up fast.

You can check out the Nooelec LNA's at that link as well.

 

[amusement]

Did you turn on the bias-t?

Yes, the t-bias was enabled.

 

[wgbecks]

I've been eyeballing the RTL-SDR wideband amplifier at Amazon (pictured below) << HERE >>. I've been wondering, does anyone here use one? If so, what are your real world results. Does it appreciably elevate the noise floor? Since I live in a rural setting, I'm thinking this may be "just the ticket", but figured it may be wise to inquire with you experts & users here first.


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Put your money into a good outdoor antenna.

 

[rabbit108]

About this, I'm assuming it's safe to use the bias-t when using the dipole software that comes with the device, correct? Sorry for the super basic question, but I'm assuming (possibly in error) that it's not a "shorted" antenna like a J-Pole. I think I read somewhere that there could be damaging results if used on the wrong type of antenna.

If you are using the RTL-SDR dongle with a dipole, but without the LNA, there is no need to turn on the Bias T.

If you are using the dipole and the LNA with the RTL-SDR dongle, when you turn on the Bias T, it will power the LNA, but the voltage should not appear at the antenna input of the LNA.

 

[rabbit108]

I don't have a diagram for the LNA, but the board shows that the power doesn't go to the LNA ANT input.



From Amazon review by Cobra176. He mentions storm damage:
https://www.amazon.com/RTL-SDR-Blog-Wideband-Amplifier-Powered/dp/B07G14Q6XX/



This is what the back of the board looks like:

 

[rabbit108]

Radio Shack made some in-line amps that had voltage on the antenna input. It was necessary to use a DC block.

 

[prcguy]

7.5dB noise figure, wow! That and the roughly 10dB gain gives you basically nothing useful.

Radio Shack made some in-line amps that had voltage on the antenna input. It was necessary to use a DC block.

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