>>>The 4-1000A has an output impedance of 4600 Ohms (according to Eimac) at
>>>5KV anode voltage.
>>? RL depends on the ZSAC. With higher idle current, RL decreases.
>>Using RL=DCV/2 x I-anode, at 0.8A, RL=3.125k-ohms. Designing for a Q of
>>15 at 28MHz, a Pi-L with an intermediate Z of 300-ohms, XC1=208 ohms,
>>C1=26pF. L1=1.5uH. L2=0.64uH. C-load=129pF. Subtracting 10pF for the
>>C-anode + stray C, C-tune is 18pF. The min. C of a UCS-300 is 5pF. Have
>>I missed something?
>Whoa! You suggest running the ZSAC at 0.8 Amps???
? 0.8A is indicated I-anode. ZSAC can be c. 20% of this current -- as
is the case for 3-500Zs. . This makes the cathode a bit easier to
drive, and it improves linearity.
>All the specs show it
>at 100 mA. You are talking about a HUGE amount of bias current and poor
>efficiency to boot.
>IMHO, 0.8A of ZSAC isn't really realizable.
? abundantly true.
>Did I miss something?
? You seemingly missed the punctuation marks in what I wrote.
- cheers, Jon.
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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