>w8jitom@postoffice.worldnet.att.net wrote:
>
>> The question begs to be asked...what meter did you use for the
>> power output reading, and the power input reading?
>
>I tried three different meters including a Bird! I did use the internal
>meters for input power. The only thing that bothers me unless the mod
>changed things, is the engineer from the factory agreed with the numbers
>I gave him! This was after several calls and lots of tries tuning. I
>have asked several times since then (over 10 years ago) if they had
>changed the design to improve the efficiency but have never gotten a
>decent answer.
It seems to me that Mr. Rauch's response has something to do with Not
Invented Here syndrome. According to Phil Clements, the tank circuit in
the AL-1200 amplifier is notably lossy on the higher bands. Numerous
RTTY-mode tank meltdowns in the AL-1200 have been reported.
- Few designers seem to realize how much current derating of conductors
is appropriate at 28MHz. For example: in order to carry 15 amperes at
50-60Hz, with reasonable loss,14 gauge wire is appropriate. However, for
carrying 15 amperes with reasonable loss at 28MHz, a 0.5" by 0.09"
rectangular conductor is needed. . {source: E. F. Johnson Co.}
note: Mr. Rauch works for MFJ/Ameritron Company.
Rich---
R. L. Measures, 805-386-3734, AG6K
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