>2 (Rich) wrote:
>> // I do not have a manual. please quote Mr, Rauch's reasonable
>Actually, I found the AL80B manual on the Ameritron web site
>(http://www.ameritron.com). Here is an excerpt from the tune-up discussion.
>Although the 400 MA figure is not mentioned (but see below), it's clear
>intent is to tune up for peak conditions and then reduce the drive for CW.
>"Increase the exciter drive power (if the ALC is not connected) until 180
>grid current is indicated. Adjust the "LOAD" and "PLATE" controls for
>output power. The grid current should not be allowed to go above 200 mA at
>stage. The plate current should not be allowed to exceed 600 milliamperes
>brief periods of tuning (15 seconds)."
>"For CW operation, the output power should be reduced with the "ALC SET"
>until the rated output power of 800 watts is obtained. The "LOAD" control
>be adjusted until minimum plate current is obtained without dropping below
>watts. The exciter's power can be reduced until the multimeter shows a slight
>upward flicker with the "MULTIMETER" switch in the ALC position if the ALC is
>"For SSB operation, the "ALC SET" should be adjusted to allow 200 mA of grid
>current (near the 20 volt marking). The exciter should be set to produce
>output power (not to exceed 100 watts of peak power).
// Eimac rates the typ. drive at 65w for 400mA of anode-I.
> Next the amplifier's
>"LOAD" and "PLATE" controls are adjusted for maximum power output on the
>internal peak reading RF wattmeter with either a two-tone generator or
>"HEL-L-L-L-L-O" driving the exciter. The "ALC SET" control should then be
>reduced until the peak power output is slightly lowered. Finally the
>audio gain or output power is adjusted until the multimeter "ALC" position
>indicates the desired ALC level. This setting should normally allow around
>mA grid current on a steady carrier or "whistle"."
>Finally, from the discussion of the ALC Set adjustment:
>"The "LOAD" control setting determines the maximum plate current and output
>power for a given grid current. Never exceed 600 mA of short duty cycle
// Incredible chutzpah. It is no surprise to me that Mr. Rauch has not
yet published the alleged Eimac letter authorizing such.
>mA of long duty cycle) plate current. Never exceed 200 mA of operating grid
// As I figure it, 200mA is c. 17w. Eimac's and Amperex's grid-diss
rating is 20w. ,
- R. L. Measures, 805.386.3734, AG6K, www.vcnet.com/measures.
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