a pretty good definition of "wideband"

Brian Hawes hawes at herald.ox.ac.uk
Mon Dec 21 14:01:18 CST 2009

Looking closer at Fig 10 (it zooms quite a lot), I wonder if this is actually a hybrid?
Did Tektronix ever make a Semiconductor version of their distributed amplifiers?
Anyway, it's just seven cascode stages distributed along two delay lines: classic.

Any thoughts on the noise properties of the d.a.? I guess that the noise contribution of each stage
adds, but incoherently, unlike a cascaded amplifier where the noise of the first stage gets multiplied.

Does a boxful of pHEMT's and two TX llines, on a PCB, give a super low-noise amplifier or is there
no free lunch?

Last one to submit a working prototype buys the Tacos!


From: Mike O'Dell [mo at ccr.org]
Sent: 21 December 2009 13:23
To: Brian Hawes
Cc: Tacos AMRAD
Subject: Re: a pretty good definition of "wideband"

i had the same flash-back!

i remember the first time i saw a schematic for one of
Tek's "distributed wideband amplifiers" and was completely
blown away.

"Everything old is new again, if you wait long enough."


Brian Hawes wrote:
> That is certainly a neat bit of chip design.
> It reminds me of the distributed deflection amplifiers in the Tektronix 500 series 'scopes.
> Brian
> ________________________________________
> From: tacos-bounces+hawes=herald.ox.ac.uk at amrad.org [tacos-bounces+hawes=herald.ox.ac.uk at amrad.org] On Behalf Of Mike O'Dell [mo at ccr.org]
> Sent: 20 December 2009 14:29
> To: Tacos AMRAD
> Subject: a pretty good definition of "wideband"
> i bet it's expensive
> http://www.avagotech.com/docs/AV02-2200EN
> _______________________________________________
> Tacos mailing list
> Tacos at amrad.org
> http://www.amrad.org/mailman/listinfo/tacos

More information about the Tacos mailing list