[AMPS] Diodes

[2@vc.net (measures)]

>
>> I was reading the HF amps section the other day, and was surprised to read
>> the flat statement that the filament choke is not necessary in
>> grounded-grid amplifiers at HF.  Or did I misunderstand?
>>
>> 73,  Pete N4ZR
>>
>That is true if you are talking about indirectly heated tubes with a separate
>cathode pin(s). The old glass tubes still need one.
>
>BTW, I see lots of ridiculously high bids for B&W FC-15's and FC-30's on
>E-Bay. Bear in mind that these do not cover 160 meters when you are bidding!
>
The 9uH fil. choke in the SB-220 works quite nicely on 160m.  To cancel 
the reactance of the choke, add approx 900pF to C2 in the 160m tuned 
input.  

cheers  

--
FAQ on WWW:               http://www.contesting.com/ampsfaq.html
Submissions:              amps@contesting.com
Administrative requests:  amps-REQUEST@contesting.com
Problems:                 owner-amps@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm