I was told that the main thing about the SDR IQ but It doesn´t record the espectrum, it has an ADC of 14 bits to 190KHZ and it costs $525.00 USD.
You think this price is good? I just have a $450.00USD Budget to buy one.
The SDR-IQ is getting a bit old now, it is pretty far behind the technology of today. That does not make it a bad receiver at all. It is as good today as it ever was, and it was something of a trend setter when it was introduced. But looking at the RFSpace web page the SDR-IQ is no longer advertised on the front page so I suspect it is either at or near end of life.
The SDR-IQ does record spectrum (I have several TB of spectrum files from the SDR-IQ that I have recorded over the years), however as you noted it only records up to 190 kHz of spectrum at one time. All SDRs have some limitation on the width of the I/Q data they can record. At the hobby level you can get up to 32 MHz of recorded bandwidth, but at a significant cost ($5000 for the WinRadio G35DDC). Most hobby oriented SDRs record 5 MHz or less of bandwidth.
Several hobby SDRs can display wider spectrums than they can record. For example the RFSpace SDR-14 can only record 190 kHz of spectrum, but can display 30 MHz of spectrum. The RFSpace NetSDR can record up to 1.6 MHz of spectrum, but can display 35 MHz in "real" mode. The WinRadio G31DDC and G33DDC can display up to 50 MHz of spectrum, but the G31 records up to 2 MHz and the G33 records up to 4 MHz.
Realistically I find I almost never need to record more than about 200 kHz of spectrum (and most frequently only 50 kHz), although I often display much wider than that. Very occasionally I will record something big, say at the WinRadio G33DDC 4 MHz width or the Elad FDM-S2 4.95 MHz width. But such recordings make up less than 0.1% of all of the recordings I have ever made. I can, however, see where a MW DXer might want to record say 1.3 MHz of width pretty often.
Keep in mind the bigger the recorded spectrum the larger the file. A 4 MHz wide WinRadio DDC recording is about 2.3 GB per minute.
The WinRadio G31DDC is an excellent radio, one of my favorites, but is well over your cost range. The G33DDC is my favorite radio, but again well over your stated price range. A close second for my favorite is the RFSpace NetSDR, very capable and a great tool.
At the lower cost end of the spectrum I would have to say the Elad FDM-S2 is about the best value. Good performance, moderate cost, wide bandwidth (both record and operate). I own one, but to tell you the truth I am not really a fan of it.
But, if I myself were looking at buying a hobby SDR today I would wait a bit. The RFSpace CloudSDR should be on the market soon, and promises to be a great value and performer. It has been suggested that the base model will be in the price range of the SDR-IQ, however will have at least 1 MHz of spectrum I/Q record at 24 bits (does this mean it can record wider at lower bit depth?) and will be able to display up to 56 MHz of spectrum. It also looks like there will be VHF options and transmit options for it. Assuming it performs as it has the potential to it will be slightly less expensive than the Elad FDM-S2 and potentially have excellent performance in the HF range. Adding the VHF/UHF option would likely push the price up above the Elad, but with potentially better VHF performance and a much wider operating bandwidth than the Elad is capable of.
T!
