The New R820T2 NooElec Mini 2

[KE4EST]

I got and have been using it for a couple of weeks but don't see a real big improvement in sensitivity or gain as I read about.
Does anyone else have one? Thoughts on it?

 

[KE4EST]

I guess I should say improvement over the first one from NooElec.

 

[Cham]

I got a new R820t2 version about a week ago. First thing I notice is better frequency stability... Don't have to re-calibrate the readout every time I plug it in or re-boot the computer. Also frequency stays fairly linear across the band(s), only out a few ppm (Hz) just about anywhere. The original could be out by several MHz at 800MHz while almost right on frequency in the FM broadcast band.

Sensitivity might be a bit better than the original... but conditions might have been enhanced on VHF the other day, picking up more NOAA weather channels than usual...

I have a feeling the original one I had might be a dud though... maybe the crystal was unstable.

For some reason my HF downconverter board has stopped working. Always something to fix!

 

[Titanium]

My NooElec mini 2 DVBT dongle and aluminum case arrived today. The frequency does seem to be more stable, but my original was pretty close and linear. Not seeing any significant difference on the sensitivity when A/B switching. Tried to match the base noise level by eye and compare a few carriers throughout the frequency range. The biggest difference was when I removed the plastic case and installed the tuner in the sweet aluminum case. The noise floor dropped noticeably.

The antenna is now a 6 section, 18", telescoping with swivel and magnetic base. Looks to be slightly more useful length than the shorty stubs supplied with most dongles.

I will be a little more technical in future testing, but quite happy with the new model and the case! I have ordered another case for the original dongle as it certainly looks better than my tin foil RF shield wrap...

 

[wallyhts]

How much do they cost? Case looks cool.

 

[KE4EST]

$26 Bucks just for the dongle.
http://www.ebay.com/itm/151463446342?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT

 

[spongella]

Purchased one of those cases a while back, very nicely made, and fits the dongle like a glove. Nooelec is always coming out with great gadgets and accessories.

By the way,you can boost your signal for frequencies above 900 MHz by using one of those in-line satellite preamps. The LA-9520 covers 900 - 2150 MHz and I use that when receiving ADS-B signals on 1090 MHz, it makes a difference. You need 12 - 18V to power the preamp, so an in-line power source (sometimes called a bias-T) is needed.

Sponge

 

[Titanium]

Be careful using inline amps as they will increase the noise and can bury threshold signals. For me, it's 50/50 with an amp. If the signal is weak, but has some level above the noise the amp may help. On other signals, the amplifier just increases the noise without improving the signal to noise ratio.

 

[spongella]

Yes, you have a great point Brian. Those in-line pre-amps never worked for me with FTA satellite. But with ADS-B signals it made quite a difference. ADS-B is on 1090 MHz. Was able to almost double the miles I could track planes in the area.

By the way, for those living in places where an outdoor antenna isn't allowed, you can build small VHF/UHF Yagis with a lot of gain, and turn them by hand inside your shack. I call it the arm-strong method. Hi Hi.

 

[KE4EST]

Strong arm is what I have called it for years.

 

[wallyhts]

Anybody try this software yet?
http://wiki.radioreference.com/index.php/Digital_Speech_Decoder_(software_package)

It allows you to decode p25

SDR then you use Virtual Audio Cable. I'm looking for my SDR and can't find the dam thing.

 

[Titanium]

Here is an article comparing the original R820T to the R820T2:
http://www.hamradioscience.com/rtl2832u-r820t-vs-rtl2832u-r820t2/

 

[Jim S.]

My T2 does have a significantly lower frequency error than the original (in fact, near 0!) but it also seems to take a significantly longer time to warm up. I don't know whether this is typical, I haven't seen anyone else mention it.