WTB: used old OSA (optical spectrum analyzer) - Page 1
Forum section: electronics / general

author: masterpj55
author_rank: Contributor
timestamp: January 15, 2021, 12:33:56 pm
content: Hello Everyone,I am looking to buy an used OSA (optical spectrum analyser). I don't have an exact budget but I'd be looking around 1200 USD (which I known isn't that big budget for an OSA)Range I'm looking for is about 600nm to 1400nm or betterIt can be an old one and data storage is not required as long as i can read out the wavelengths.I'm trying to measure the wavelengths 808nm and 1278nm of a laser light source.I have a hene to calibrate this unit to and some known laser light sources if needed.I'm aware these units are big so shipping can be a pretty penny (like 250~300 USD) easily but I'm willing to pay that (parcelmonkey is a good place to arrange that through).Happy for offers or leads! Tried ebay but sadly it's either broken + sold at a really high price.

author: mjs
author_rank: Regular Contributor
timestamp: January 15, 2021, 04:57:45 pm
content: Some time ago I got HP 70950 and 70004 mainframe separately for around 2000€. Great machine with good resolution.Unfortunately it seems that one company that borrowed it has broken it - I'll see on Monday. Be careful when shipping or moving these, apparently there are some delicate moving parts with enough mass to break themselves. If it's really broken, there will be teardown.

author: _Wim_
author_rank: Super Contributor
timestamp: January 15, 2021, 08:02:40 pm
content: Quote from: masterpj55 on January 15, 2021, 12:33:56 pmWhat kind of resolution you need? Are those fiber coupled lasers? Many OSA have a single mode fiber input, which can make life difficult if you want to couple other light sources into it. Do you need the spectrum, of just the peak wavelength (in which case a wavelength meter might also be an option)?

author: masterpj55
author_rank: Contributor
timestamp: January 15, 2021, 08:04:14 pm
content: I want to measure one range of wavelength at a time.For example i'd like to verify a 808nm laser if its really doing close to the 808nmor I wanna verify if at a further stage in the optical train the conversions are taking place at the "aproximate correct wavelengths" so about 5nm worst case range.The lasers are not fiber coupled.. i would put a fiber close to the beam and measure scatter from it.. because the power from the lasers would be too much for the sensor.just peak wavelength by the way!

author: masterpj55
author_rank: Contributor
timestamp: January 15, 2021, 08:06:40 pm
content: Quote from: mjs on January 15, 2021, 04:57:45 pmgood to know. If shipping damage occurs.. how likely is fixing it?The weight is most certainly going to make things move in most situations and I wonder how the pandemic and package handeling have come together.I will be interested if it works and does not generate an error perhaps!2000 euros however is quite high above my budget.. but worst case something I'd consider.. that is a good machine indeed!Edit: where are you based country wise?

author: _Wim_
author_rank: Super Contributor
timestamp: January 15, 2021, 08:32:00 pm
content: Quote from: masterpj55 on January 15, 2021, 08:04:14 pmFor that kind of resolution I would be looking for a CCD based spectrometer, but 1400nm will be too high, these typically max out around 1100nm (unless ingaas based sensor, but then they start only around 900nm). Thinks of brands like Ocean Optics and Avaspec. These typically work with large diameter fiber inputs, which make is very easy to couple light into it. These are also usb based, light and small, so shipping is not an issue. Prices are around 500€ to 700€. Resolution varies depending on range and slit size (typically between 0.5 and 10nm)Quote from: masterpj55 on January 15, 2021, 08:04:14 pmYou will be surprised how difficult it is to get this right with a single mode fiber input. Your signal will be too high or too low. I own an Anritsu MS9710C, and it quite difficult to test anything that is not single mode fiber coupled to start with. There are some free space optic OSA's, but these tend to be even more expensive due to their versatility. As you found out, these can be expensive. I bought mine broken, but still paid around 700€ for it, which was a big gamble.Quote from: masterpj55 on January 15, 2021, 08:04:14 pmThen a wavelength meter is the ideal tool. Very high accuracy and high sensitivity. I own an Anritsu MF91A with a 0.6µm to 1µm plug-in. It has about 0.01nm resolution. It was around 200€ on Ebay (which was probably a good deal).

author: masterpj55
author_rank: Contributor
timestamp: January 15, 2021, 08:48:31 pm
content: Quote from: _Wim_ on January 15, 2021, 08:32:00 pmCorrect the regular ccd spectrometers don't go higher then 1100 to even 1000nm max.I really need to reach that 1278nm.The problem I found with the more common usb spectrometers is that the regular ones go to that 1100nm at best and the deep IR ones go to a minimum of 900nm.,. on top of that the deep IR ones are a rare find.. new 50~60k and never seen them show up on ebay.. so OSA was my second consideration.The wavelength meter is a GREAT idea! Sadly I haven't been able to find any any on ebay it's still in the thousands.. amazing deal on yours though!I noticed good deals for OSA's that have "slit errors" which seems like a high price gamble for something that might not be repairable.Open for wavelength meter suggestions!

author: _Wim_
author_rank: Super Contributor
timestamp: January 15, 2021, 09:26:08 pm
content: Quote from: masterpj55 on January 15, 2021, 08:48:31 pmJust had a look on Ebay for wavelength meters, it is indeed not a cheap option for the moment also. Mine doesn't cover you range, so it is of no help (doesn't get used here very often, as in the meanwhile I acquired quite a bit of other options...)About repairing an OSA, it is indeed a big gamble. Mine was quite an easy fix (reseating all connector is I remember correctly), but that is off course no guarantee.Another option could be a monochromator, on which you install a silicon photodiode or ingaas photodiode, depending of which laser you are testing. I am currently working on one, which I am automating with an arduino cnc shield. I have calibrated it using the spectral line of both a neon bulb and mercury vapor lamp, and achieved a wavelength accuracy of about 0.3nm, and similar resolution. With the installed grating (1200mines/mm 500nm blaze) I can achieve this from +-250nm to 1200nm, but with a different grating it would easily cover your required range (using higher or modes with an optical filter at the input is for high power light sources also an option).Monochromators are quite affordable on Ebay (200€ to 500€), but are always a project and not ready to use. For computer controlled ready to use versions expect to pay quite a bit more

author: pico61
author_rank: Contributor
timestamp: January 17, 2021, 09:03:02 am
content: I want to sell my Anritsu MS96A optical spectrum analyzer. The analyzer is in good working order. I want 520 euro + sc. The only problem is that it weighs a lot, about 30 kg.If you are interested, please send me a PM.

author: masterpj55
author_rank: Contributor
timestamp: January 17, 2021, 11:23:51 am
content: Intestested! send you a message.Parcelmonkey is really the best way to ship during these times especially with big packages.Hopefully you have a box that fits this thing though.Willing to pay the hefty shipping cost.

author: mjs
author_rank: Regular Contributor
timestamp: January 18, 2021, 08:06:46 pm
content: I'm based in Finland - now visible in my profile, too.Looks like you're getting a nice deal for the Anritsu - looks very similar performance to the HP unit!

author: _Wim_
author_rank: Super Contributor
timestamp: January 19, 2021, 06:20:40 pm
content: Quote from: mjs on January 18, 2021, 08:06:46 pmWhere did you find a datasheet? Somehow I cannot seem to find it online. The only info I can find is "0.6 um - 1.75 um Wavelength Resolution: 0.1 nm Additional Information:The MS96a is the predecessor of the MS9710A"

author: masterpj55
author_rank: Contributor
timestamp: January 19, 2021, 07:42:50 pm
content: Bought the anritsu from pico!Great price and extremely honest seller! Very happy.Will take some days to ship but this will do exactly what I want!I'm working on an OPSL laser hence I required these deep IR wavelength (they are comparible to how DPSS lasers function but with more odd wavelengths and more stages in the optical train).I could also not find a datasheet or manual for the anritsu but it's ok.I have however seen sellers show a paper manual in their images.. I think nobody has ever scanned in any of it due to it's age.

author: _Wim_
author_rank: Super Contributor
timestamp: January 19, 2021, 08:06:30 pm
content: Quote from: masterpj55 on January 19, 2021, 07:42:50 pmI thought maybe mjs found somewhere the datasheet because of his comparison with the HP unit.Definitely interested in the OPSL laser project if you are able to share more (best in a separate thread so we do not to use the buy/sell section).Also interested to see your results with the MS96A. Attached a screenshot of a few lasers I measured with the MS9710C: an HP 5517B (from my laser interferro meter, really narrow bandwitdh and stable) and a fiber laser used in communication (older device).

author: masterpj55
author_rank: Contributor
timestamp: January 20, 2021, 01:28:02 am
content: hi yes. I might do a thread on it!It's a high current low voltage analog controlled laser source that can make odd colors like monochromatic yellow or orange (non color mixed true orange or yellow for short)How do you feed the laser into the fiber that goes into the OSA?I reckon you can't just shoot a couple of wats down the fiber into the sensor as the energy will destroy the sensor.The source I'm measuring will be around the 40 to 20watts range.. so for sure not something you want to give to a sensor.Do you place the fibers ending close to the laser and take on the scatter? Or do you attenuate the energy somehow??I bought a fiber (vis-nir) from ebay with sma connector (seeing on the anritsu there is a threaded cap on there made me assume it is sma)The update rate on the anritsu seemed a bit slow for the measure on a video I recieved (sweep) but perhaps it can be sped up reducing it's resolution ?

author: _Wim_
author_rank: Super Contributor
timestamp: January 20, 2021, 06:19:51 pm
content: Quote from: masterpj55 on January 20, 2021, 01:28:02 amI started a new thread here to continue discussing:https://www.eevblog.com/forum/testgear/fun-with-optical-spectrum-analyzers-spectrometers-and-monochromators/

author: masterpj55
author_rank: Contributor
timestamp: January 25, 2021, 07:38:49 pm
content: Optical spectrum analyzer send by pico61 arrived!It was very well packed and it works great!Very happy with it thank you!

author: _Wim_
author_rank: Super Contributor
timestamp: January 25, 2021, 08:15:40 pm
content: Quote from: masterpj55 on January 25, 2021, 07:38:49 pm

author: pico61
author_rank: Contributor
timestamp: January 26, 2021, 06:35:00 pm
content: I am happy that you were satisfied with the Anritsu MS96A. Thank you too!