In article ,
Chuck wrote:

Scott wrote:
I think I might have found a modern alternative...a very small surface
mount device that looks like it will do exactly what the HP doubler does
AND only $5.95 in SINGLE quantities (The AMK-2-13+)!!

Not "exactly".

Guaranteed F1 in the output is only -20
dBc. Not nearly as good as a DBM.

Scott-

I've read past postings that discussed Minicircuits.com and the 8640B
doubler. Why not contact them and ask if they have a better
alternative? They may be familiar with the 8640B, and have addressed
the question before.

Regarding Jeff's comment, I was of the impression that the signal was
generated at a high level prior to the attenuator, and attenuator
settings were correct for the 512-1024 band as well as the others.
Since your "8640B in a can" has the 512-1024 switch position, it should
be possible to install a home-made doubler in the same space where the
HP doubler would go, prior to the attenuator.

Fred
K4DII