Best Real Time Cheap Spectrum Analyzer choices, 2021 Version

[RChadwick]

Wile I have LONG wanted a decent Spectrum Analyzer, over the years I've collected a few 'Wannabe' items, like an IM-ME that scans limited ranges, an old handheld analyzer with a 0.1Hz sweep rate, a HackRF Portapack, and various programs and RTL-SDR. I now have a job where it would help immensely if I could identify interference to Wifi and 4G. My budget is under $150, as it's out of pocket. I almost purchased one of these: https://www.ebay.com/itm/224369540898 or this one for under $100 https://www.ebay.com/itm/124720883296 , but I haven't seen any reviews, and similar ones seem to have slow sweep rates and significant artifacts. I considered a TinySA, but I need 2.5GHz or over. I looked at the RF Explorer line, but displays are tiny and they look like toys. While a single device is preferable, Satsagen looked interesting. I already have RTL-SDR, HackRF, LimeSDR, and a PlutoSDR. I remember seeing a project from around 2014 that used a Raspberry Pi, LCD and an RTL-SDR, and it updated pretty fast. Accuracy isn't as important as cheap and fast, giving a pic ture of what's going on around. What's everyone's favorite cheap Spectrum Analyzer these days? What's the best under $200 2.5GHZ+ Spectrum Analyzer?

[Bicurico]

With your budget of 150-200 £/$/€ you will not find any spectrum analyser that is better than the SMA/NWT/D6/LTDZ devices (these implement swept spectrum analysis and are too slow for WIFI analysis) or the HackRF One/ADALM Pluto (these could be used for WIFI analysis and you already own a HackRF One).

While the Portapack is a great add-on for the HackRF One, you would want to use it without the Portapack or in the HackRF One mode. Attach it to the PC and use it with this so ftware: https://github.com/pavsa/hackrf-spectrum-analyzer

This is the best you can do with your budget!

Next best thing would be the Arinst SSA-R2 TG (check my blog on the signature - I have recently written a test report on this device). It will cost you around 400 £/$/€ shipped + customs from Russia.

If you REALLY want a REAL-TIME Spectrum Analyzer, then your "cheapest" option would be the Siglent SSA3000-R Series. Depending if you want to analyse 2.4GHz and/or 5GHz Wifi, you might need the SSA3075-R model (not sure if the SSA3050-R would be enough). Note that it seems you can hack the SSA3032-R into an SSA3075-R, but better check it here on the forum.

Anyway, this option would probably be just about 20 times your budget! And yes, that is the cheapest option for a professional low-cost realtime spectrum analyzer.

You might want to check SignalHound, too, but I am not so familiar with their products and prices.

Regards,
Vitor

[RChadwick]

Thanks for the response! While a pro model with 3 or more 0s is off the table, I might just break down and get an Arinst, but I'll try the HackRF first.

A quick question. As far as quickly detecting Sub-GHz transmitters, would you recommend a TinySA? Would a RF Explorer be better?

[rfclown]

Nothing is free. From what I've worked with, the cheapest real time analyzer is the ADALM PLUTO. But it's just the hardware, not an out-of-the-box solution. You've got some software work to do. $150 at Digikey. I have two of these, but I'm still working on the software side. But it does do Tx and Rx with arbitrary signals. I can do WiFi Tx and Rx, both 2.4 and 5.8 GHz bands.

[joeqsmith]

I have been using the Signal Hound BB60C for the past five years but it's limited to 20MHz.  Tektronix has one that I think was 40MHz.   I posted some data for the Signal Hound here.  Sadly, at $150 I don't think you would find a used broken one.   

https://www.eevblog.com/forum/testgear/why-are-old-spectrum-analyzers-so-expensive/msg1093943/#msg1093943

[rfclown]

Thanks for the response! While a pro model with 3 or more 0s is off the table, I might just break down and get an Arinst, but I'll try the HackRF first.

A quick question. As far as quickly detecting Sub-GHz transmitters, would you recommend a TinySA? Would a RF Explorer be better?

For quickly detecting sub-Ghz transmitters you can use an RTL-SDR. They are dirt cheap. But you have to handle the software.

[Bicurico]

Thanks for the response! While a pro model with 3 or more 0s is off the table, I might just break down and get an Arinst, but I'll try the HackRF first.

A quick question. As far as quickly detecting Sub-GHz transmitters, would you recommend a TinySA? Would a RF Explorer be better?

For quickly detecting sub-Ghz transmitters you can use an RTL-SDR. They are dirt cheap. But you have to handle the software.

OP said he has a "Portapack", which is actually a add-on board for the HackRF One, that allows to use it independantly from a computer.

All OP has to do is to put the device in "HackRF One" mode and connect it to a PC running Windows. Then he just has to run the software I linked in my original reply (alternatively he could use Satsagen). This implements a pretty nice real-time spectrum analyzer (with some obvious limitations, though). This is the best he will ever get for his budget and in reality he does not have to spend any more money, as he ALREADY OWNS the required device!

Recommening an RTL-SDR does not make much sense, as it is worse than a HackRF One (2MHz RT span vs 10MHz RT span).

Also, why recommend an ADALM Pluto, if it is more or less similar to the HackRF in this application (I know it can simultaneously do RX/TX, while the HackRF is assynchronous RX/TX).

There are, IMHO, only two options:
1) Stick with what is already available
2) Increase the budget by around 20 times, to get something truly better