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FFT analyzer recommendations

Started by Phil Hobbs February 16, 2018
Hi, all,

I need another FFT analyzer.  I really like my HP 35660A, but it only 
goes up to 100 kHz (50 kHz for two-channel measurements).  I'd really 
like one that goes up to at least 10 MHz, and can do the same sorts of 
stuff, especially display noise spectral density in different units on 
different scales and perform frequency response testing easily.

There are a bunch of USB-style things, which might be okay as long as 
they have Linux software available.

What I really want is a smallish boat anchor with two channels, 14-16 
bit resolution, > 50 MS/s sampling, FFT analysis, a nice display, and 
that can talk to USB sticks.

Any faves?

Thanks

Phil Hobbs

-- 
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Friday, February 16, 2018 at 9:59:38 AM UTC-5, Phil Hobbs wrote:
> Hi, all, > > I need another FFT analyzer. I really like my HP 35660A, but it only > goes up to 100 kHz (50 kHz for two-channel measurements). I'd really > like one that goes up to at least 10 MHz, and can do the same sorts of > stuff, especially display noise spectral density in different units on > different scales and perform frequency response testing easily. > > There are a bunch of USB-style things, which might be okay as long as > they have Linux software available. > > What I really want is a smallish boat anchor with two channels, 14-16 > bit resolution, > 50 MS/s sampling, FFT analysis, a nice display, and > that can talk to USB sticks. > > Any faves? > > Thanks > > Phil Hobbs > > -- > Dr Philip C D Hobbs > Principal Consultant > ElectroOptical Innovations LLC / Hobbs ElectroOptics > Optics, Electro-optics, Photonics, Analog Electronics > Briarcliff Manor NY 10510 > > http://electrooptical.net > http://hobbs-eo.com
I think you should buy one of the Rigol SA's and report back. Specifically the cheap DSA815-TG. https://www.rigolna.com/products/spectrum-analyzers/dsa800/ George H.
The Rigols are RF spectrum analyzers, and I already have three of those. I'm looking for a more modern version of the HP 89410A, basically. 

Cheers

Phil Hobbs
On Friday, February 16, 2018 at 12:35:18 PM UTC-5, pcdh...@gmail.com wrote:
> The Rigols are RF spectrum analyzers, and I already have three of those. I'm looking for a more modern version of the HP 89410A, basically.
Oh are the Rigols OK? I want a SA that goes above 100k Hz too. ~10 MHz would be enough for lots of stuff. Are the Rigols any use in the 1 MHz - 10 MHz range? George h.
> > Cheers > > Phil Hobbs
On 02/16/2018 01:48 PM, George Herold wrote:
> On Friday, February 16, 2018 at 12:35:18 PM UTC-5, pcdh...@gmail.com wrote: >> The Rigols are RF spectrum analyzers, and I already have three of those. I'm looking for a more modern version of the HP 89410A, basically. > > Oh are the Rigols OK? I want a SA that goes above 100k Hz too. > ~10 MHz would be enough for lots of stuff. Are the Rigols any use > in the 1 MHz - 10 MHz range? > > George h.
Entry level SAs are all SDR-based these days, so they make nice pictures and are pretty flexible compared with traditional ones, and in the low-frequency range they're probably fine. I hang on to my 8566es because their close-in phase noise is unbeatable due to their YIG-tuned oscillators and filters, but that really only becomes important above ~100 MHz. If you're OK with a noise floor around -80 dB from full scale, the Rigol is probably fine, and it's not at all a bad price. Cheers Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net https://hobbs-eo.com
On Friday, February 16, 2018 at 3:22:51 PM UTC-5, Phil Hobbs wrote:
> On 02/16/2018 01:48 PM, George Herold wrote: > > On Friday, February 16, 2018 at 12:35:18 PM UTC-5, pcdh...@gmail.com wrote: > >> The Rigols are RF spectrum analyzers, and I already have three of those. I'm looking for a more modern version of the HP 89410A, basically. > > > > Oh are the Rigols OK? I want a SA that goes above 100k Hz too. > > ~10 MHz would be enough for lots of stuff. Are the Rigols any use > > in the 1 MHz - 10 MHz range? > > > > George h. > > Entry level SAs are all SDR-based these days, so they make nice pictures > and are pretty flexible compared with traditional ones, and in the > low-frequency range they're probably fine. I hang on to my 8566es > because their close-in phase noise is unbeatable due to their YIG-tuned > oscillators and filters, but that really only becomes important above > ~100 MHz. > > If you're OK with a noise floor around -80 dB from full scale, the Rigol > is probably fine, and it's not at all a bad price.
Thanks Phil, 80 dB is better than the 50 dB I get with my 'scope FFT. GH
> > Cheers > > Phil Hobbs > > > -- > Dr Philip C D Hobbs > Principal Consultant > ElectroOptical Innovations LLC / Hobbs ElectroOptics > Optics, Electro-optics, Photonics, Analog Electronics > Briarcliff Manor NY 10510 > > http://electrooptical.net > https://hobbs-eo.com
Okay, so I put in an eBay 'best offer' on an HP 89441A vector signal analyzer with the two-input option. We'll see!

Cheers

Phil Hobbs 

-- 
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC / Hobbs ElectroOptics 
Optics, Electro-optics, Photonics, Analog Electronics 
Briarcliff Manor NY 10510 

http://electrooptical.net 
http://hobbs-eo.com 


Feb 16
Am 18.02.2018 um 01:44 schrieb pcdhobbs@gmail.com:
> Okay, so I put in an eBay 'best offer' on an HP 89441A vector signal analyzer with the two-input option. We'll see! >
I have written a program that controls that thing over the network and measures spectra from 0.1 Hz to 1MHz, one FFT per decade, reads the results, combines them and plots them with gnuplot. One needs a converter box from coax ethernet to contemporary network, then one just opens port 5000-something on 192.168.178.111 and simply reads and writes GPIB-strings. And the coax needs 2 terminations, even when the "cable" is only 5 inch long. :-) No need for GPIB cards and semi-supported drivers. These measurements of voltage regulator noise have been done with it: < https://www.flickr.com/photos/137684711@N07/24070698809/in/album-72157662535945536/ > Just in case you win it and are interested. cheers, Gerhard
>I have written a program that controls that thing over the network >and measures spectra from 0.1 Hz to 1MHz, one FFT per decade, reads >the results, combines them and plots them with gnuplot.
>One needs a converter box from coax ethernet to contemporary network, >then one just opens port 5000-something on 192.168.178.111 and simply >reads and writes GPIB-strings. And the coax needs 2 terminations, even >when the "cable" is only 5 inch long. :-)
>No need for GPIB cards and semi-supported drivers.
>These measurements of voltage regulator noise have been done with it:
< https://www.flickr.com/photos/137684711@N07/24070698809/in/album-72157662535945536/ &nbsp; &nbsp;>
>Just in case you win it and are interested.
Hi, Gerhard, I did, and I am. I'll have to gin up a nice low-1/f-noise preamp for it, but that'll be fun. Thanks Phil Hobbs -- Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC / Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics Briarcliff Manor NY 10510 http://electrooptical.net https://hobbs-eo.com
On 21/02/2018 01:29, pcdhobbs@gmail.com wrote:
>> I have written a program that controls that thing over the network >> and measures spectra from 0.1 Hz to 1MHz, one FFT per decade, reads >> the results, combines them and plots them with gnuplot. > >> One needs a converter box from coax ethernet to contemporary network, >> then one just opens port 5000-something on 192.168.178.111 and simply >> reads and writes GPIB-strings. And the coax needs 2 terminations, even >> when the "cable" is only 5 inch long. :-) > >> No need for GPIB cards and semi-supported drivers. > >> These measurements of voltage regulator noise have been done with it: > < > https://www.flickr.com/photos/137684711@N07/24070698809/in/album-72157662535945536/ > > > > >> Just in case you win it and are interested. > > Hi, Gerhard, > > I did, and I am. I'll have to gin up a nice low-1/f-noise preamp for it, but that'll be fun. > > Thanks > > Phil Hobbs >
Note that the software options can easily be unlocked on these (although they would be of little use for your intended application).