[Amps] Amplifier Linearity

[Bryan Swadener]

--- Edwin Karl wrote:
> Does anyone besides me still use a 'scope in
> trapezoid pattern looking
> at input vs. output linearity?
> 
> Seems like we're getting into "flat topping" tubes,
> etc just to get the max.
> output level etc.
> 
> All the "it can't happen here" talk is really
> counter productive. If a guy
> says
> he can do it for heaven's sake let it go. Please
> don't try and prove how
> clever you
> are. It just doesn't impress me and wastes my time.
> 
> Thanks
> 
> 73
> 
> ed K0KL

Hi Ed,

You can count me as one who saw the light in the 70s. 
I had purchased my used SB220 and (at first) adjusted
it for maximum CW/single-tone output before operating
in the SSB mode.  It was shortly afterward that I
acquired the Heathkit 'twins' (SB-610 & SB-620)
monitor scopes, and learned from a 2-tone/trapezoid
test that I was NOWHERE near the linear region.  More
loading was the cure. Until I have a peak limiter
installed ahead of the mic input, I monitor in
real-time with the scope in envelope mode.

I understand the gadget du jour is some CW key-line
pulser.  I have yet to read anything as to how it can
ensure linear operation (without the use of an
oscilloscope of any kind).  So far, I'm unimpressed.
Vy 73,
Bryan WA7PRC


       
____________________________________________________________________________________
Building a website is a piece of cake. Yahoo! Small Business gives you all the tools to get online.
http://smallbusiness.yahoo.com/webhosting