>sounds to me like the .82 ohm grid meter shunt resistior has assumed a
>different value. If it becomes an open then the multimetr will try to
>fly across the room (mine did). Suggest you replace the resistor and
>also
>add a 10 ohm 25 watt resistor from point B on the diode board to ground.
>This will protect the multimeter should the .82 ohm shunt open in the
>future.
I do not think this will protect the multimeter. Based on circumstantial
evidence, the current pulse that opens the 0.82 ohm resistor, R1, can
exceed 15a. A good way to protect the meters is with 3a Si diodes.
Also, there is no reason put the multimeter in grid-I position. The
amplifier can not be tuned up with the grid-I meter and Eimac has no
recommendation or maximum rating for 3-500Z grid current.
Rich---
R. L. Measures, 805-386-3734, AG6K
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