>Class AB2 and class B operation for triodes is (was) very
>common. Just think of all those modulators and Broadcast TV transmitters
>etc. The main problem with HF operation is the fact to
>have broad band neutralization required a balanced output
>tank circuit.
? Bridge-neutralization and an unbalanced Pi tank could provide general
coverage Class AB1 operation for a (low-Mu) triode - as it does with
tetrodes and pentodes. . See Figure 5 on my Web site. The only change
needed for a triode is to decrease the ratio of the bridge capacitances.
- A problem with grid-driven Class AB2 and Class B operation is c.
minus 20db ssb-voice IMD. Even though this is perfectly FCC-legal as
long as the feculence stays within the amateur service band in use,
anyone who runs high power with high distortion is quite likely to be
viewed as an anathema.
> This is quite a problem if you want to
>band switch. It was common to change coils to change bands.
>
- later, Bill
>
>At 11:23 AM 3/30/99 -0800, you wrote:
>>>
>>>Rich says:
>>>
>>> >/ grid-driven '''Linear''' amplifier, one needs a triode operated in
>>>>Class AB1.
>>>
>>>Not necessarily. There's always Class AB2 with grid current.
>>
>>? With the 4CX1500B & 4CX600JX, yes, provided that the grid current does
>>not exceed 0.5mA. Specify a triode for Class AB1 grid-driven linear
>>service, and I'll have a go at it with the appropriate
>>characteristic-curves
>>
>>- later, Peter. .
>>
>>
>>
>>Rich...
>>
>>R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
>>
>>
>>--
>>FAQ on WWW: http://www.contesting.com/ampfaq.html
>>Submissions: amps@contesting.com
>>Administrative requests: amps-REQUEST@contesting.com
>>Problems: owner-amps@contesting.com
>>Search: http://www.contesting.com/km9p/search.htm
>>
>>
>
> William L. Fuqua III P.E. E-mail WLFUQU00@POP.UKY.EDU Phone (606)
>257-4155
> Department of Physics and Astronomy CP-177 Chem. Phys. Bldg.
> University of Kentucky , Lexington, Ky 40506-0055
>
>
>
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
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