[Amps] Re: [CQ-Contest] Italian power explained -

[Richard]

>At 04:59 PM 3/10/02 EST, you wrote:
>>Found these 20 and 30kw Italian antenna tuners on the web: 
>> 
>>http://i5uxj-2.cln.it/amp/hfamp.html 
>
>It looks as if the Italians aren't the only ones -- check this JA example
>out, further down on the same page:
>
>http://i5uxj-2.cln.it/amp/schemi/aag/aag.html  
>
>It's really quite beautifully built.
>
€  Beautifully built, however it,:
1.  is not neutralized.

2,  does not have the variable vacuum caps vertically mounted as is 
recommended.

3.  uses paralleled DC blocker caps (makes an addiitional VHF resonanance 
in the anode circuit. 

4.  has the L of L-supp and the L of R-supp approx equal.  To design an 
optimal VHF parasite suppressor, these two inductances need to be as 
different as is feasable. 

5.  has gaps in the winding of the HV-RFC which do not ameliorate the 
resonance problem as claimed. 

6.  has much wasted space inside.  My guess is that, like the natives in 
New Guinea and their up to 4" x 22" phallocarps, the designer wanted to 
display a "big one".  

>I was also intrigued to read that I5UXJ's flagship amp, running a
>4CX15,000, claims 21 KW output with 70 watts drive.  No wonder you never
>see the amps in pictures of Italian stations! 

A 4cx15,000A will, on SSB with a 200w driver, do 36 out, so RG-213 is 
definitely out.  Three-phase 480v mains are desireable.  The good news 
about the 4cx15.000 is that it does not make X-rays like it's big brother 
the 4cx35,000C.   As I understand it, there is a JA who runs a 
commercially-built 4cx35,000C.  
>
cheers, Pete

-  R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K, 
www.vcnet.com/measures.  
end