![Microvolts to dbm](https://kumkoniak.com/73.jpg)
![microvolts to dbm microvolts to dbm](https://www.pdffiller.com/preview/227/845/227845337.png)
How do these receivers perform when connected to an outside antenna? In my previous post I showed that the RSPduo performs better than the RSP1A in the LF band under lab conditions. Tests were also done using on-air signals and these are in the next post. You can see screenshots showing test results on my Google Drive >. Results were very close to those published by SDRplay RSPduo Tuner 1 HiZ 0.16 microvolts (-123.2 dbm) **** Normalized to 50 ohm RSPduo Tuner 1 SMA 1.97 microvolts (-101.1 dBm) Tested Sensitivity for SSB/CW signal kHz, - 1.8 kHz. In order to verify these figures I did some tests on my own equipment using a signal generator. RSPduo Tuner 1 HiZ 0.18 microvolts **** HiZ port is 1000 ohms but microvolt sensitivity has been normalized to 50 ohm Published Sensitivity for SSB/CW signal kHz, - 1.5 kHz. In my post above I gave the following specs for sensitivity below 500 kHz. High noise in LF MW blotted out.jpg (196.33 KiB) Viewed 20153 times My preliminary humble opinion is that the main problem of Sabrina lies with antenna coupling to the receiver and spurious generation due to strong MW Broadcasting stations.
#Microvolts to dbm Pc
Furthermore I am not sure that the RSPduo or (even more unlikely) the RSP2 should deliver such performance at LF, nor convinced that a sensitivity of -135 dBm would make any difference (tests pending) at a receive frequency of 300 KHz, because of antenna noise, see PC screen below taken from:
![microvolts to dbm microvolts to dbm](https://www.rlocman.ru/i/Image/2011/12/21/Fig_03.jpg)
Looking at these figures one sees that the sensitivity advantage between High Z and 50 Ohm inputs would appear to be in the order of 35 dB and not of 10/12 db, as would look more likely and confirmed by experience. The HiZ port and the built-in MW rejection filter give the best weak signal reception below 500 kHz. For serious LF DXers the duo is the best choice. It is the lowest cost member of the family but offers great value. The RSP1A is a good SDR receiver but it has some limitations compared to the RSP2 and the RSPduo. SDRplay do not publish detailed NF specs for the RSP2 but in my experience I find slightly worse performance than the RSPduo but better than the RSP1A. **** HiZ port is 1000 ohms but microvolt sensitivity has been converted to 50 ohm Sensitivity for SSB/CW signal kHz, - 1.5 kHz.
#Microvolts to dbm mod
Sensitivity for AM signal 136 kHz, - with 60% Mod - 12 dB SINAD
![microvolts to dbm microvolts to dbm](https://www.teich-filter.de/media/images/solar-inselanlage-12v-100w-stoer-kl.jpg)
This data is from the SDRplay data sheets for each product. Here are some specs comparing the RSPduo with the RSP1A. SDRplay has published data that shows the 50 ohm ports of the RSP1A, RSP2 and RSPduo have about a 10 dB higher noise floor than the HiZ port of an RSP2 or RSP duo at 1 MHz. The lower the Noise Figure the better when looking for weak signals under these conditions. However there is only so much you can do with a receiver that has a high noise figure (NF) below 500 kHz when you use a poor antenna. I made a few suggestions like using Low IF, Setting the LO to 1000 kHz and using external MW reject filters and preselectors.
#Microvolts to dbm how to
Sabrina1984 was wondering why the performance of the RSP1A was not doing as well as the NRD525 and looking for tips on how to improve performance. Better compare 50 ohm of all sets to have best idea. Sdrom33 wrote:Hi z inputs cannot be compared with 50 ohm in of rsp1a.
![Microvolts to dbm](https://kumkoniak.com/73.jpg)