Help me identify a thing I found in my old Surplus box - Page 1
Forum section: electronics / rf-microwave

author: n3mmr
author_rank: Regular Contributor
timestamp: September 27, 2019, 01:05:45 pm
content: Little grey metal box.Label says Oak Frequency Control.Model no OSC91-88A-H08.There's an SMA jack on one side, and 4 short pins on the underside, 3 stick out thru some isolating material, and a 4th is connected to the metal chassis.I tried googling to no avail.Help! Pretty please!

author: xrunner
author_rank: Super Contributor
timestamp: September 27, 2019, 01:20:05 pm
content: Prolly a crystal oscillator like this oneeBay auction: #173857530136

author: m3vuv
author_rank: Super Contributor
timestamp: September 27, 2019, 01:37:25 pm
content: looks to me like a xtal oscillator,the 10mhz makes me think its possibly from a frequency counter for a frequency cal check,mine has similar,ive got a takeda riken has a simmilar lump in it.

author: n3mmr
author_rank: Regular Contributor
timestamp: September 27, 2019, 02:51:10 pm
content: Quote from: BravoV on September 27, 2019, 01:17:56 pmPiccies now added to OP.

author: n3mmr
author_rank: Regular Contributor
timestamp: September 27, 2019, 02:54:30 pm
content: A complete/ideal answer should include how-to-connect and what to expect on the output.Or an actual datasheet.I really want to connect and see the oscillation on the SMA jack...

author: xrunner
author_rank: Super Contributor
timestamp: September 27, 2019, 04:50:26 pm
content: Quote from: n3mmr on September 27, 2019, 02:54:30 pmI gave a complete/ideal answer to the question you asked ^^^ (which was very simple to find by an internet search).QuoteNow, you are asking for more than you originally did. Why can't YOU find the data sheet for yourself?

author: DimitriP
author_rank: Super Contributor
timestamp: September 27, 2019, 05:04:24 pm
content: Quote<insert ideal really nasty comment / rant here>

author: DimitriP
author_rank: Super Contributor
timestamp: September 27, 2019, 05:06:53 pm
content: Quote from: xrunner on September 27, 2019, 04:50:26 pmthere is this thing, called the internet , where you can find forums where there is always n (n > 1) people who will do ALL the legwork for you , spoon feed you the answer , hold your hand, change your diaper and burp you after a meal ... ideally.

author: n3mmr
author_rank: Regular Contributor
timestamp: September 28, 2019, 08:52:42 am
content: Quote from: xrunner on September 27, 2019, 04:50:26 pmI tried, and tried and tried.As I said, I googled to no avail. If it had been there I ought to have found it.No such luck.If someone could tell me how to connect the thing, or suggest what to google for, I would be very happy.I googled for the model number, Oak Frequency Control, Ovenaire and many other things. I learned that Oak was bought by Corning inthe nineties, but I couldn"t find any tech info on this little thingie.

author: RoGeorge
author_rank: Super Contributor
timestamp: September 28, 2019, 10:47:01 am
content: Looks to me like an ovenized quartz oscillator. Probably made in 1992, week 52.I'll expect it to output 100.837264 MHz at the SMA connector. The Tx/Rx paper label seems to be an info about the whole apparatus (and not about the oscillator can alone). The Ovenaire was probably part of a 10 GHz communication equipment.Two pins must be VCC and GND (most probably the diagonal ones are the VCC/GND), and the 3rd pin I expect it to be either a reference output, an input for fine frequency adjustment, or an input for enable/disable the oscillator.GND should be easy to identify by checking for electric continuity between the metal can and one of the 3 pins on the back.Once you know the GND pin, look with an ohm-meter for the VCC pin, you will see something like a variation because some filtering capacitance must be connected internally between Vcc and GND.Judging by the age of the can, the Vcc should be at least +5Vcc (no 3v3 or lower), so I'll start from powering the can with 5Vcc and looking for oscillations at the SMA or at the remaining pin on the back.The remaining pin might be an input enable/disable pin, or maybe an open collector output, so if no oscillations are to be seen, I'll try tying it through a 100 ohms or so to Vcc or GND and see if oscillations appears either at the SMA connector or at my remaining pin.If still nothing, maybe this Ovenaire is for 9V or 12V Vcc. Try again all the above procedure, this time with higher Vcc, but only after you are sure it doesn't work with 5V no matter what.Would be good to power the can from a power source that can limit the current.Again, I don't know that device and I don't know much about manufacturing habits for ovenized oscillators, but that's what I'll try to do.

author: n3mmr
author_rank: Regular Contributor
timestamp: September 28, 2019, 11:08:50 am
content: Quote from: RoGeorge on September 28, 2019, 10:47:01 amThere are 4 pins, one is directly attached to the metal of the can.I'll start by doing roughly what you suggest, and be back when I have more knfo.Thanks for the educational effort!

author: Gyro
author_rank: Super Contributor
timestamp: September 28, 2019, 11:17:52 am
content: Just a note that theremaybe separate supply connections for the oscillator and the oven, it depends whether there's an internal regulator for the oscillator supply. Just something to keep in mind. EDIT: Or it may be a TCXO.