Looking to buy a replacement part to repair an Agilent 8643A signal
generator. It's an ECL divide-by-2 device. Would like to get the original
part if anyone has one they'd like to sell, but even substitute parts
suggestions would be very welcome.

Part Number: 1820-2101
Description: IC Divider ECL Binary 4-metal Package

Other equipment where part is used according to Agilent:
* 5355A
* 8643A
* 8644B
* 8645A
* 8664A
* 8665A
* 8665B
* E5501A
* E5501B
* E5502B
* E5503A
* E5503B
* E5504A
* E5504B

I've posted a schematic of the particular circuit in
alt.binaries.schematics.electronic:
Subject: Agilent 1820-2101 for 8643A signal generator -
8643A-divide-by-2.jpg (1/1)
Date: Fri, 03 Jun 2011 06:16:20 -0400
Message-ID:

U15 is the defective part. The schematic does not show the GND connection,
but the case is GND. The package style is similar to TO-39. It's expected
frequency input at J3 is 520MHz to 1030MHz.

Thanks.