Ono Sokki CF-910 FFT Analyser - Page 1
Forum section: electronics / general

author: dexters_lab
author_rank: Unknown
timestamp: November 11, 2012, 04:07:13 pm
content: been a long while since i wandered around here!i picked up a Ono Sokki CF-910 FFT Analyser off ebay for, well... no particular reason other than it looked interestingand was cheap enough that if it didn't work or wasn't that exciting i wouldn't be that bothered.Well it is working just fine, weighs about 20Kg (!) but it seems to be intended for audio usage as its response is 1Hz to 40KHzSo i have it here in my pink lab, it dates from 1985 going from the IC dates. I have pulled most of it apart except the front panel (which does contain a few more boards) and its rammed full! It's all through hole, few Zilog 8000 CPUs, floating point processor etc.Anyway, i was interested in looking up the spec of the A/D converter, i'm guessing its going to be about 80ksps () given the 40khz fft response but i cant seem to find any datasheet on the two MA6197A converters. Any ideas?There should be some pics attached, can post more & videos if anyone is interested?The pic of the board on it's own is one of the analog front-end boards, i'm not sure but i dont think they used enough relays on it, it needs more!This board is paired with another board that has the A/D converter.

author: dexters_lab
author_rank: Unknown
timestamp: November 27, 2012, 08:10:06 am
content: No interest?I was hoping to learn a bit more about what area of work this unit was intended for, it does have some interesting maths functions (i have no idea what they are though, maths isnt my strong point!)I was thinking maybe do a teardown of some description as i need to replace some damaged bnc's on the rear panel

author: EEVblog
author_rank: Unknown
timestamp: November 27, 2012, 09:43:41 am
content: I used to have a CF-350 OnoSoki DSA. Not the most user friendly beast!Dave.

author: dexters_lab
author_rank: Unknown
timestamp: November 27, 2012, 03:11:25 pm
content: Looks a very similar unit, have figured out most of its functions (well those i understand!) With a little help from a crib sheet provided by ono sokki.

author: T4P
author_rank: Super Contributor
timestamp: November 27, 2012, 05:44:34 pm
content: "Portable"AwesomeReminds me of the Tek scopes discussed quite a long time ago here that was advertised as "Portable" Weighing over 10kg!

author: dexters_lab
author_rank: Unknown
timestamp: November 27, 2012, 06:38:01 pm
content: I guess they had to make a portable one, the 910 checks in at 27kg!

author: vk6zgo
author_rank: Super Contributor
timestamp: November 28, 2012, 01:29:43 am
content: Quote from: T4P on November 27, 2012, 05:44:34 pmI can't believe how wimpy modern EEs & Techs are!That's a lot more portable than a Tektronix 524AD!

author: T4P
author_rank: Super Contributor
timestamp: November 28, 2012, 06:35:04 am
content: Quote from: vk6zgo on November 28, 2012, 01:29:43 amWell that's why old Techs are always so buff and such from carrying the 524AD! My analog scope i got the other day didn't even weigh in near 10kgJoking aside i am logically capable of carrying around 10kg but i have a bad shoulder todayProbably from hauling a 30kg box the other day (God knows what it is but it was marked "ANALYZER")

author: EEVblog
author_rank: Unknown
timestamp: November 28, 2012, 10:53:34 am
content: Quote from: dexters_lab on November 27, 2012, 08:10:06 amThis is what is also called a "Dynamic Signal Analyser" (DSA), and they are primarily used in the sound and vibration measurement industry.In the seismic industry I worked in, a DSA like this was used more often than a scope, it was the tool of choice.Powerful features like cross-correlation allow you to tell how much of a signal if due to (correlated to) the input signal, and how much is due to noise etc, among much other stuff.I've had two in my lab over the years, and wish I had kept one, but I sold both on ebay due to space. The other one was a Rockland.HP/Agilent make the industry standard DSA, and the Stanford Research one is nice too.Dave.

author: dexters_lab
author_rank: Unknown
timestamp: November 28, 2012, 05:14:37 pm
content: Thanks Dave, this unit seems to have come from a truck / van manufacturer (leyland daf), we speculated it might have been for measuring noise in the drivers cab, but i guess it could also be used for more mechanical measurement in the driveline/engine.Once i fix the busted bnc connectors on the back a friend wants to use it for some audio work, then i will probably sell it on, i just dont have the room to keep something this big and heavy!