unkown ic

[smokyLED]

I'm trying to find a replacement for an IC in my frequency counter.
It's a 8 pin DIP, and could possible be a opamp. But i'm not sure. I have googled but haven't had any luck.

This is with is printed on the package:
TFK 731 666 BS

TFK666BS seems to be the product code.

Thanks in advance.

[aProgrammer]

I think this could be
a U666BS telefunken (TFK) prescaler

http://www.alphacron.de/download/hardware/U666.pdf

[smokyLED]

I think this could be
a U666BS telefunken (TFK) prescaler

http://www.alphacron.de/download/hardware/U666.pdf

thanks for finding that.