>no rich..not ok for SSB nor for shortwave...something to do with switching
>speeds. i assume when i say not linear, i also mean not good for SSB
>
** So why would a Ham want a not-linear amplifier?
>also a question not related to this thread......what would be the issue of
>running 3,800 volts on a pair of 3-500Zs? im rebuilding an SB-220 and may
>do an outboard power supply...thanks......steven W4IIV
** The bandswitch in a SB-220 is not very ok with a 3800vdc anode
supply. 3000v is close to the limit for a SB-220. If one needs more
output it takes at least 4x as much suds to make a noticable difference.
The difference between a SB-220 and a tetrode with handles is only c. 1.7
S-units.
>"R. Measures" <r@somis.org> wrote:
>** Not linear is OK for SSB? The difference in S-units between an
>amplifier that 60% efficient and an amplifier that is 90% efficient - for
>the same power input - is 0.3 S-units, or 1.76db.
>
>>http://hawkins.pair.com/wabcnow.shtml should give you a heads up on the
>>operation of these broadcasting beasts.
>>they are totally digital, and uses square waves for RF genoration...they
>>are not linear..but they are 90% efficient......steven, W4IIV
>>
>>"R.Measures" wrote:
>>
>>
>>>This couldn't be farther from the truth...
>>
>>** Dr. Schmidt. Please explain why high-efficiency BC-type designs are
>>suitable for applications where linear operation over a range of
>>frequencies is required. Tnx
>>>
>>>Sincerely,
>>>
>>>Dr. William J. Schmidt, II K9HZ
>>>Trustee of the North American QRO - Central Division Club - K9ZC
>>>
>>>"Collector of Edison Wind-up Phonographs... Do you have one for me?"
>>>Email: bill@wjschmidt.com
>>>Alternate Email: wmschmidt@charter.net
>>>WebPage: www.wjschmidt.com
>>>
>>>
>>>
>>>----- Original Message -----
>>>From: "R.Measures"
>>>To: ; " AMPS"
>>>Sent: Monday, December 15, 2003 10:25 AM
>>>Subject: Re: [Amps] Big Solid State Power Amplifiers
>>>
>>>
>>>>
>>>>
>>>> >I don't know what designs you are familiar with, but combiner losses
>>>don't
>>>> >usually impact significantly on efficiency. That's why they are used in
>>>> >high-efficiency AM BC transmitters...
>>>> >
>>>> **High-efficiency BC-type designs are not suitable for applications where
>>>> linear operation over a range of frequencies is required.
>>>> _______________________________________________
>>>> Amps mailing list
>>>> Amps@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>>
>>_______________________________________________
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>>
>>
>>STEVEN GRANT W4IIV
>>
>>
>>---------------------------------
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>
>
>STEVEN GRANT W4IIV
>
>
>---------------------------------
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