We now sell RTL-SDR’s with the R820T2 Tuner and 2x Telescopic Antenna + R820T2 Tests

We now sell R820T2 RTL-SDRs on Amazon.com (currently for US customers only sorry!) and are currently running a $2 off promotional sale which will expire January 31, or until the first batch of stock runs out. Compared to the other choices our RTL-SDR Blog branded units come with several improvements which we list below.

  • Use of the R820T2 tuner which has been shown to have slightly better noise performance and give better SNR compared to the standard R820T chip.
  • Use of improved component tolerances which help the circuit to operate at its optimum.
  • Use of a surface mount 28.8 MHz oscillator instead of the “can” type. We believe this will reduce the PPM offsets to below 30 in most dongles, but note we can not guarantee this.
  • Improved “full braid” coax cable on the antenna base which has significantly lower loss compared to the coax used on other brand RTL-SDR stock antennas.
  • Comes with 2 x telescopic antennas. 1 x 9.5 cm to 31.5 cm telescopic antenna and 1 x 20 cm to 1.5 m telescopic antenna. Great for beginners to receive a wider range of frequencies without buying extra antennas.
  • No IR LED. The IR LED is useless for SDR operation and the long legs on the LED may pick up interference.

We currently have two options for sale that are shown below. The dongle only unit is perfect as a replacement dongle or for those who just want to try out the R820T2 chip. The unit with the two telescopic antennas is great for beginners who don’t have any good antennas already.

We also have limited quantities of some MCX male to various female adapter sets for sale which work out to be much cheaper than when buying them individually. Buying a set will have you ready for almost any antenna connection you need. The pigtail adapters come with 20cm of RG316 cable and the straight adapters don’t use any cabling.

Pigtail Adapters SetMCX -> Various Female Pigtail Adapter Set – $19.99

Straight MCX Adapters SetClick here to buy a MCX -> Various Female Straight Adapter Set – $16.99

Currently because of the way Amazon works, we can only ship to US customers, but we may ship overseas in the future. Shipping from Amazon is fast and free if you spend over $35 or are a Prime member. Returns from faults are also easy and welcome. If you are overseas and can’t buy from us, the alternatives for R820T2’s are the Nooelec R820T2 (US shipper), the Cosycave R820T2 (ships from Channel Islands, UK) and there are also some Chinese R820T2 (Chinese shipper) models available on ebay.

We also offer unofficial support over on our forums. If you do buy from us we hope that you will consider leaving a product review on the Amazon page as that will really help us out as small time Amazon sellers.

As an added bonus, we will also have our e-book on sale from January 16 to January 23 at $6.99 USD, reduced from $9.99 USD.

We also performed some simple performance tests on the R820T2 which we show below.

R820T2 Tests

The first test was a noise floor test. We used rtl_power and ran a noise test with maximum gain and a 50 Ohm terminator connected for 15 minutes over the entire receivable frequency band. We averaged the results over three different R820T dongles and three R820T2 dongles to remove dongle to dongle variances. The results show that noise floor on the R820T2 is around 2-3 dB lower at most frequencies.

R820T2_NoiseFloor

Next we tested the SNR with the gain set to zero using a HackRF as the signal source. The results show that the R820T2 is about 2-5 dB more sensitive depending on the frequency. Also, compared to the R820T, the sensitivity seems to be significantly better at 1.5 GHz to 1.8 GHz as all tested R820T units could not even detect the test signal above 1.5 GHz without increasing the gain.

R820T2_SNR

Oliver Jowett HF Driver Test

The R820T2 should have better performance at HF frequencies when using the experimental Oliver Jowett drivers. We tested an R820T and R820T2 on broadcast AM reception. At broadcast AM frequencies the R820T starts with a very high noise floor after starting it for the first time, but after about 5 minutes seems to settle down to a lower noise floor shown in the right image below. In comparison the R820T2 starts at a low noise floor almost immediately. We are unsure why there is a settling time in the first place. Even after the settling time the R820T2 had better reception and SNR as shown in the comparison image below. Both dongles were set to the second highest gain setting.

R820T2vR820T_BAM

At 15 MHz international broadcast AM can be clearly heard with Oliver’s drivers. The R820T2 gets clear reception with a very low gain setting, whilst the R820T can obtain similar SNR with a higher gain setting. Though with a higher gain setting used on the R820T more noise seems to appear as can be seen in the comparison image below.
R820T2vsR820T_14MHz

Low Loss Coax

We also tested the low loss coax cable used in our RTL-SDR Blog branded antenna bases and found that it had approximately 3 dB less loss compared to the standard cable when used at most frequencies above 100 MHz. The test used a 1M length of each coax, with the HackRF as the signal generator. The direct connection test used a straight MCX->SMA Male adapter to directly connect the HackRF and RTL-SDR together.

Low_Loss_Coax

19 comments

  1. Peter

    Cute little package, but not very sensitive using either whip antennas. It could barely hear the local PD about a mile away on VHF high using either whip.

  2. JUAN

    omnidirectional antenna connect it 118-136 with 50 Ohms coaxial cable that brings the same RadarBox ComStation.
    With negative air band reception

  3. Gabe

    HI;
    I want to purchase the RTL-SDR Blog R820T2 RTL2832U in Canada (Ontario) and Shipped there as well. Amazon won”t ship the item to Canada – no idea why. Can you please send me a link to a Canadian source. ’73

  4. Prototype

    Looks like this kit is sold out on Amazon. Do we know when and if there will be more restocked?

    • admin

      We’re working on the next version which will have some more improvements. They’re in production now, but still about 2 months away unfortunately.

  5. JMG

    The tuners R820T and R820T2 both have the same sensitivity: a noise figure of NF=3,5dB.
    The noise level N of S/N is NOT the noise of the ADC. That is what you measured. It is the noise of the tuner.
    S/N can be measured in the spectrum display. Increasing the gain from zero should bring the noise floor roughly 10dB above the ADC noise. Applying a defined signal will give you the correct S/N ratio then.
    There are new gain settings in the R820T2. This lowers the indicated noise floor at zero gain. It gives some improvement in the dynamic range.

  6. Pat

    I might as well ask here, that experimental driver does absolutely nothing for me.

    http://i.imgur.com/Ykbofdt.png

    Maybe it is working but I have heavy interference? My antenna is the default telescopic one but I added a portable clip on antenna that I use with my portable shortwave.

    • Joe Brown

      Since a few days you can get those in Europe from this guy in the UK (Jersey Island)
      https://www.cosycave.co.uk/product.php?id_product=320
      The guy even does a quick test and resolders the antenna connector – what a service!
      He also offers very good prices on adaptors and USB powered LNAs.
      I just ordered a few bare R820T2s and they should get here without the usual tax on top when buying stuff from China. They are even cheaper than buying them directly from the manufacturer (Newsky) in China. Seems like my price negotiation skills are not the best?!
      Two years ago I bought a few R820T based sticks from him and they got here (Germany) in a flash, very fast delivered and very well packed with attention to the detail – outstanding service.

      When asking for the latest specs and data sheet with the tuner manufacturer “Rafael” on the differences there reply was as follows: “… Allow me to explain to you that R820T2 is the same spec and function as R820T” which is total BS and then they attached the R820T datasheet :-(.
      What would else be the point in creating a new one – just to keep the R&D department busy?! Probably not!
      I guess we all have see these weird spurious oscillations that run through the spectrum even when no antenna is connected and I still wonder if they are coming from the internal DC/DC switched voltage regulator or from the oscillator on the tuner chip?!

      Anyway I am glad to see there is a difference and now I am anxious to try my R820T2 in a few days and will report how they do in real life.

      Many thanks to the RTL-SDR site editors – you do a great job – love this site!

      • Graham

        I can confirm the quality of the service. I have two LNAs from there. The chip on one failed and he repaired it very quickly. He deserves all the trade!

      • Dave

        Cosycave are great to deal with and I’d recommend them to anyone looking for an SDR bargain and fast, friendly, efficient service.

    • admin

      RG174 has a standard impedance of 50 Ohms. The mismatch between 75 and 50 Ohms is negligible, so the impedance doesn’t really matter for RX.

      The coax is the same as on the standard antenna base, but with a “fully braided” coax shield and a stranded inner wire. You can see the difference on the last image in the Amazon listing.

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