[Amps] Future of RF AMPS

[Gary K9GS]

Here ya go:

http://www.acom-bg.com/amplifiers3x2000.html

There was a picture floating around a few months ago showing an Italian 
ham that had a special high power version of this combiner. He was using 
three SS Expert 2KW amps.


On 9/11/2013 1:20 PM, Richard Solomon 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
>>>
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-- 


73,

Gary K9GS

Greater Milwaukee DX Association: http://www.gmdxa.org
Society of Midwest Contesters: http://www.w9smc.com
CW Ops #1032   http://www.cwops.org

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