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Electronics => Beginners => Topic started by: alank2 on July 13, 2020, 01:45:38 am

Title: Isotemp OCXO pinout question - I can't find a datasheet
Post by: alank2 on July 13, 2020, 01:45:38 am

It is about 2" by 1" by 1" tall and looking at it from the underside it has:

Code: [Select]

3
2             P
1

pins 2 and P are grounded to the case.
pin 1 has 4.7K resistance to ground.
pin 3 has 5M resistance to ground.

Is pin 1 the VCC and pin 3 the output?

Any guesses at the voltage?  I'm thinking 12V, but I'm not sure I want to give it that much as a test unless I know for sure.

Title: Re: Isotemp OCXO pinout question - I can't find a datasheet
Post by: alank2 on July 13, 2020, 02:17:14 am

I think it is this:

https://web.archive.org/web/20030608212454/http://www.isotemp.com/ocxo23.htm (https://web.archive.org/web/20030608212454/http://www.isotemp.com/ocxo23.htm)

Title: Re: Isotemp OCXO pinout question - I can't find a datasheet
Post by: alank2 on July 15, 2020, 07:00:46 pm

Could this require a load for it to work properly?

The link above says "into 50 ohms".

Sometimes it works great with no load except the scope, but then I've seen it snap to another frequency like 6.7 MHz.  Once that happens it is only cleaned up by me putting a resistor between the output and ground.  100 ohms works, 50 ohms works, 250 ohms does not work.