a pretty good definition of "wideband"

Mike O'Dell mo at ccr.org
Tue Dec 22 11:04:53 CST 2009


i believe Tek did build a hybrid solid state version
for the later high-end machines.

and i bet if you go looking for SSAs (solid-state amplifiers)
to replace TWTs aboard satellites, you'll find some hideously
expensive hybrids which look a lot like what you suggest.

	-mo


Brian Hawes wrote:
> 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!
> 
> Brian
> G2KQ
> 
> 
> 
> ________________________________________
> 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."
> 
>         -mo
> 
> 
> 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