RTL Dongle Upgrade From V2 To V3 Worth It?

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Is there any performance improvement from the version 3 dongle over version 2 on VHF / UHF? They say version 3 has less noise. Will it actually work any better than version 2? I don't use HF, but better sensitivity and a lower noise floor on VHF / UHF would be great.
 

slicerwizard

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I picked up a couple of v3 dongles plus the monster 58 inch telescoping magmounts and the FM filters. The combination of those three items is working better for me than the v2 dongles did with some dual band VHF/UHF magmounts. I can monitor stuff from the couch that used to be unworkable.
 

princessthelus

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V3, I think allows the bias-tee to work without having to solder any thing and has a resetable fuse
 

SCPD

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HB - some antennas have a pre-amp that is powered by DC (say 5 - 12 volts) provided though the antenna coax.
 

mancow

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Bias is basically DC voltage riding on the same path as AC. T meaning the DC joins the AC path in a T junction. It's a simplified way of saying that they are injecting DC power up the same connection as the antenna. That way the Preamp near the antenna can be powered without the need for a separate DC cable.
 

thewraith2008

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V3, I think allows the bias-tee to work without having to solder any thing and has a resetable fuse
The resettable fuse is only available in the 2nd batch of V3 dongles.

Make sure it's the 2nd batch of V3 dongles you get. As mentioned below, that's is supposed to be the one shipping now.

Worth noting about V3 batch 1. The text below from here: RTL-SDR Blog V.3. Dongles User Guide - rtl-sdr.com

Known V3 Batch 1 Issues:

Increased sideband noise on very strong narrowband signals. This should not be a significant problem as it only affects very strong signals. The hardware fix is to add about 100-220uF of capacitance on the 3.3V power line. Batch 2 will reduce this noise.
The bias tee when turned on adds a large spur in direct sampling HF mode. This may be problematic only if you intend to use a bias tee powered HF LNA in direct sampling mode. This can be fixed by adding about 2.2uF of capacitance to the output of the LDO, before the inductor. Batch 2 will fix this.
The bias tee can be damaged by accidentally short circuiting the output for a few seconds while it is on. This damage only occurs on USB3.0 and USB2.0 ports that can provide up to 1A or more or current. Batch 2 will add a resettable fuse to prevent damage.

Batch 2 and newer (Shipping Now):

No known issues.
 
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I went ahead and got 2 version 3's last week and they're working fine. So hopefully they are the 2nd batch. But the receive and noise performance have been exactly the same as the version 2's I had.

Now this bias-tee thing sounds cool and makes we wanna get a couple pre-amps to try. But don't pre-amps have mixed results in the scanning hobby? There's a lot of threads where people say the pre-amp makes it worse, causes interference, or maybe messes up digital decoding. So is there a good pre-amp that anyone makes that works well with these dongles?
 

thewraith2008

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Probably depends on your intended receiving signal and if your surrounded by strong signals which will cause greater frontend overload with a pre-amp. Pre-amps may work better with ADS-B signals and those that are by nature weak.

LNA4ALL is one that's available. Not sure if it's good or not:
LNA4All Low Noise Amplifier Review - rtl-sdr.com

The guy who makes them also has a some YouTube videos explain some stuff about it and its benefits.

search YouTube "adam 9a4qv lna"

Cheers
 
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