I noticed that the efficiency of the 13.56 MHz amplifier is 85% max and the
27.12 MHz is 78%. Dropping down rapidly at higher frequencies. But all this
efficiency would be lost if you linearize the amplifier. And don't hold you
breath waiting for carbon nano-technology to produce something useful for
hams.
73
Bill wa4lav
At 09:44 AM 3/29/2005 -0500, Bert wrote:
>Very interesting!! Solid state is the way to go.
>
>73s Bert, VE3OBU
>
>
>
>-----Original Message-----
>From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
>Behalf Of Dr. William J. Schmidt, II
>Sent: Tuesday, March 29, 2005 2:08 AM
>To: craxd1@ezwv.com; amps@contesting.com
>Subject: Re: [Amps] Transistor amps
>
>Check these out... I just uploaded them to my website. They make fine CW
>amps... need a little work for SSB... but not much!
>
>http://www.wjschmidt.com/ham/apt9502.pdf
>
>http://www.wjschmidt.com/ham/apt9701.pdf
>
>Sincerely,
>
>Dr. William J. Schmidt, II K9HZ
>Trustee of the North American QRO - Central Division Club - K9ZC
>
>Email: bill@wjschmidt.com
>WebPage: www.wjschmidt.com
>
>"If computers get too powerful, we can organize them into a committee; that
>will do them in." -- Bradley's Bromide
>
>
>----- Original Message -----
>From: "Will Matney" <craxd1@ezwv.com>
>To: <amps@contesting.com>
>Sent: Monday, March 28, 2005 8:54 PM
>Subject: Re: [Amps] Transistor amps
>
>
> > William,
> >
> > If things convert over to solid state, that is what's needed, a high
> > voltage semiconductor. This I am interested in and wouldn't mind building
> > a prototype. One thing about mosfets I was told is you can parallel them.
> > You can parallel say 4 on each side of a push pull amp (8 total) to
> > increase it's power. This way, you dont have to worry about all those
> > splitters and combiners.
> >
> > Thanks,
> >
> > Will
> >
> > *********** REPLY SEPARATOR ***********
> >
> >>On 3/28/05 at 7:38 PM Dr. William J. Schmidt, II wrote:
> >>
> >>>Frequency response rolls off too much for those transistors. They were
> >>>made
> >>>to work below 2 mhz. HOWEVER, there are the high voltage mosfets from
> >>>Advanced Power Technology that work in the 300-1,200 VDC range deserve
> >>>discussion. The devices are targeted for RF designs < 75 Mhz, and are
> >>>very
> >>>cheap by most measures (not Rich). Lots of class "E" circuits for
> >>them...
> >>>APT has many app notes on them... check them out!
> >>>
> >>>Sincerely,
> >>>
> >>>Dr. William J. Schmidt, II K9HZ
> >>>Trustee of the North American QRO - Central Division Club - K9ZC
> >>>
> >>>Email: bill@wjschmidt.com
> >>>WebPage: www.wjschmidt.com
> >>>
> >>>"If computers get too powerful, we can organize them into a committee;
> >>>that
> >>>will do them in." -- Bradley's Bromide
> >>>
> >>>
> >>>----- Original Message -----
> >>>From: "Will Matney" <craxd1@ezwv.com>
> >>>To: <amps@contesting.com>
> >>>Sent: Monday, March 28, 2005 7:08 PM
> >>>Subject: [Amps] Transistor amps
> >>>
> >>>
> >>>> This is something I have thought of for years and never looked into it.
> >>>> Could an amp be built using horizontal output transistors where the
> >>>> voltage can be ran up to keep the current down? I wonder if any would
> >>>work
> >>>> up in this frequency range (2-30 MHz)?
> >>>>
> >>>> Will
> >>>>
> >>>> _______________________________________________
> >>>> Amps mailing list
> >>>> Amps@contesting.com
> >>>> http://lists.contesting.com/mailman/listinfo/amps
> >>>>
> >>>
> >>>
> >>>_______________________________________________
> >>>Amps mailing list
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> >>>http://lists.contesting.com/mailman/listinfo/amps
> >>
> >>
> >
> > *********** END FORWARDED MESSAGE ***********
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
>
>
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