[Amps] Future of RF AMPS

[dsolberg at wi.rr.com]

Richard,

Communication Concepts sells combiners that should work. http://www.communication-concepts.com/index.php/splitter-combiners.html

Don
K9AQ
---- Richard Solomon <dickw1ksz at gmail.com> wrote: 
> Rumor has it that RF Parts offered a High Power Combiner, but a search of
> that site
> does not show it. There are a few Combiners, but no Data to tell what they
> do.
> 
> Anyone have a source for a Combiner that will handle 2X 600 to 800 Watts in
> ??
> 
> 73, Dick, W1KSZ
> 
> 
> On Wed, Sep 11, 2013 at 9:41 AM, <dsolberg at wi.rr.com> wrote:
> 
> > While the MOSFETs can output 1200 watts with four in parallel/push-pull,
> > the output transformer ratio will limit the practical output to between 800
> > and 1KW, using a 9:1 with a 50V power supply.  The 9:1 optimal output is at
> > 800 watts.  Tokyo HyPower uses this design and they rate it for 1KW.  I can
> > also get 1KW with my homebrew amp with (4) SD2933's, but prefer to run it
> > closer to 800 watts to improve the IMD.
> >
> > If you really want the full legal limit, you would be better to have two
> > PA modules and a combiner.  Otherwise the output transformer design is
> > going to get real complicated.  The other option is running higher voltage,
> > which complicates the selection of a power supply.  50 volt computer server
> > switching power supplies are low cost and easy to obtain.
> >
> > I am happy with 800-1KW, but maybe someday I will try the combiner just
> > for the fun of it.
> >
> > Don
> > K9AQ
> > ---- Leigh Turner <invertech at frontierisp.net.au> wrote:
> > >
> > > Larry, the RF power MOSFETS to which I refer here are the VRF2933 devices
> > > from Microsemi. Sometimes one can find surplus and NOS ST Micro SD2933
> > FETS
> > > on eBay at low prices.
> > >
> > > 4 of these rugged 300 Watt rated devices in parallel/push-pull will
> > yield a
> > > saturated output power of well over 1200 Watts.  Six will comfortably
> > yield
> > > over the US legal limit.
> > >
> > > 73
> > >
> > > Leigh
> > > VK5KLT
> > >
> > > -----Original Message-----
> > > From: Amps [mailto:amps-bounces at contesting.com] On Behalf Of Larry
> > > Sent: Wednesday, 11 September 2013 10:48 AM
> > > To: amps at contesting.com
> > > Subject: Re: [Amps] Future of RF AMPS
> > >
> > > On 10-Sep-13 5:51 PM, Leigh Turner wrote: using a readily available
> > > multiplicity (6 devices in parallel/push-pull) of cheap 50V MOSFETS
> > sourced
> > > from the surplus market.
> > >
> > >
> > > Leigh,
> > >
> > > Exactly which cheap MOSFETS from what surplus market are you speaking of?
> > >
> > > Larry - W7IUV
> > >
> > > _______________________________________________
> > > Amps mailing list
> > > Amps at contesting.com
> > > http://lists.contesting.com/mailman/listinfo/amps
> > >
> > >
> > >
> > > _______________________________________________
> > > Amps mailing list
> > > Amps at contesting.com
> > > http://lists.contesting.com/mailman/listinfo/amps
> >
> > _______________________________________________
> > Amps mailing list
> > Amps at contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps