They posted imd graph image on there Facebook page:
https://www.facebook.com/groups/b26.pa/permalink/1528268827191800/
Looks like 80 meter test at 1.5k using a flex radio transceiver.
73
Zev n2wks
On Fri, Jun 2, 2017 at 1:49 PM Herbert Schoenbohm <
herbert.schoenbohm@xxxxxxxxx> wrote:
> As the old times in the Midwest used to say...."Never buy a pig in a poke"☺
>
>
> Herb, KV4FZ
>
>
> On 6/2/2017 1:01 PM, Jim Thomson wrote:
> > Date: Thu, 1 Jun 2017 18:48:55 +0000
> > From: Bill Turner <dezrat@xxxxxxxxxxx>
> > To: Amps group <amps@xxxxxxxxxxxxxx>
> > Subject: Re: [Amps] RF-KIT SS AMP
> >
> > <It looks pretty good on paper but the real world sometimes has
> > <unpleasant surprises in store. I wouldn't buy one until it gets
> > <reviewed by an independent third party such as QST. It's real easy to
> > <lay out $3k and before long wish you hadn't.
> >
> > <A word to the wise.
> >
> > <73, Bill W6WRT
> >
> >
> > ## agreed, qst..or at least a handful of experienced tech savvy
> types, who can
> > make meaningful measurements..including imd, etc, and offer a critque.
> >
> > ## I also noticed they reduce power output by reducing the current
> limit on the power
> > supply.... vs reducing drive. This method, I have not heard of
> before. One would think it
> > would flat top 1st..once it hit the current limit threshold ? But I
> have zero experience with it.
> >
> > ## I have zero experience with SS amps. My concern is the TX IMD
> products. Reducing
> > drive and PO is one method that would work..but eff goes to
> hell..fast. Diss then increases with just
> > the typ 35% when po reduced.... while maintaining 48-50 vdc.
> >
> > ## another method to reduce IMD may be to just increase the idle
> current a bunch.
> > I have no experience with that either..except on tube amps. But I
> suspect the eff might creep up
> > a little, and perhaps slightly reduced IMD. Then again, the increased
> idle current would result in
> > a higher average dissipation.
> >
> > ## A combo of reduced drive, and higher idle current might be the
> ticket, but Im just speculating.
> > The faster 120mm fans could be used to handle the increased idle
> current. Its not like the SS amp
> > has to reside on the desk, it could sit anywhere...like in my shop next
> door. Noise problem solved.
> >
> > Jim VE7RF
> >
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> > Amps@xxxxxxxxxxxxxx
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>
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