Piezo Crystal Company 2900082-85 OCXO pinout - Page 1
Forum section: electronics / rf-microwave

author: feedback.loop
author_rank: Frequent Contributor
timestamp: January 05, 2018, 05:41:39 am
content: Hi!Does anybody know the pinout of this device?It has 5 wires: black red, green, orange and white.Thank you very much.

author: RFMWdude
author_rank: Contributor
timestamp: February 05, 2018, 08:00:10 pm
content: The following eBay (France) listing at least gives some specs, including the supply voltage:http://www.ebay.fr/itm/322218336142There's also an email address mentioned where you can get a datasheet.The 3 bundled wires were probably connected to a potentiometer, for fine tuning the frequency.In that case, they are:- Reference Voltage Output (5V?)- Control Voltage Input (0-5V?)- Ground(A 10kOhm potentiometer is suggested in the eBay listing.)And the other two wires are +12V and groundAre any of the wires connected to the metal can?Disclaimer: I'm just guessing, so don't complain if the magic smoke escapesGreetings from a fan of your Youtube channel.

author: feedback.loop
author_rank: Frequent Contributor
timestamp: February 07, 2018, 06:12:39 am
content: The black wire is connected to the metal can. I decided to risk it, and applied 12V 0.1A limited supply to the orange wire. The current hit the limit, the voltage was about 9.4V, but no output.

author: RFMWdude
author_rank: Contributor
timestamp: February 07, 2018, 06:34:51 pm
content: Please see the attached file for a connection diagram and some datasheets.With many thanks to the eBay seller!The OCXO can draw up to 800mA at startup, so it is not surprising that you hit the current limit.

author: feedback.loop
author_rank: Frequent Contributor
timestamp: February 08, 2018, 04:52:22 am
content: Quote from: RFMWdude on February 07, 2018, 06:34:51 pmRight, it is not surprising that it hit the current limit, but I expected to see some output. Perhaps, an unstable one, but something.

author: feedback.loop
author_rank: Frequent Contributor
timestamp: February 08, 2018, 05:14:30 am
content: Quote from: RFMWdude on February 07, 2018, 06:34:51 pmThe document is about 2900082-48 not -85. The colors make sense, but there are also pin numbers and extra pins mentioned (like 1 not connected). My unit doesn't have any numbers, but a bunch of wires sticking out of the side of the can.

author: feedback.loop
author_rank: Frequent Contributor
timestamp: February 08, 2018, 06:03:23 am
content: I increased the current limit to 0.8A. The thing started drawing about 0.6A and stabilized around 0.2A. This makes sense, but there is no output.

author: RFMWdude
author_rank: Contributor
timestamp: February 08, 2018, 11:13:23 pm
content: Is the reference voltage (5V) available at the red or green wire?What happens when you connect a pot to the wires?What happens when you connect a low impedance (50 Ohm) load to the output?If nothing helps, then you at least have an interesting subject for a teardown & repair video

author: feedback.loop
author_rank: Frequent Contributor
timestamp: February 09, 2018, 07:10:18 am
content: No voltage on green, white or red. I tried a pot with no change. The output I connected to my spectrum analyzer, so the 50 ohm load was present. Perhaps, the thing is dead. Or this model might have a different pinout.