>
>First, we have to assume Rich is unbiased and telling the truth.
>
>Assuming that:
>
>> At 2250 watts output, an 8877 draws less than 65 ma grid current.
>> 75 ma limiting is plenty of headroom. A cap sits in the base circuit
>> of the TIP120 to prevent nuisence trips.
>
>75 mA is not plenty of headroom Phil.
>
>At 3300 volts anode, a typical 8877 requires 125 mA of grid current
>to produce 2500 watts output, At 125 mA of grid current, grid
>dissipation is 11 watts.
>
>At 175 mA, grid dissipation is 18 watts.
>
>These figures are from Eimac's tube calculation software.
>
>> > Ever ran an 8877 with no suppressor whatsoever?
>>
>> I have not personally, but if you look at old Orr and ARRL Handbooks, you
>> will see several 8877 projects sans the Supp.
>
>All of this hysteria is caused by one person. Eimac has never
>found a "VHF sputtered grid" in an 8877 returned from an Ameritron
>amp.
>
Eimac's warranty department does not test returns for gold-sputtering.
>
end
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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