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Equipment / Re: Odd behavior from Ameritron Amplifier
« on: December 28, 2015, 2215 UTC »
C/P from somewhere:
Carefully remove # 500Z tube..check... amp plate volts should be indicated. Key amp and observe reading on volt scale..should be same as unkeyed amp with tube Removed. Continue to move meter switch to current ranges..no idle current 150/200 indicates that the 3 500Z is the shorted proublem...D117 is also the meter protection diode and the 2 small caps beside often fail together (tube arking inside, tube short's ,to lite of loading control can cause arcking inside tube and tank stage. B+ is on tube at standby or operate, "operate switch" controls the bypass relay remote key line and with tube removed the procedure will help pin down what often is a internal tube defect that is a shorted 3 500Z.
KC7QNM, Apr 28, 2011
Any updates?
rgg
Carefully remove # 500Z tube..check... amp plate volts should be indicated. Key amp and observe reading on volt scale..should be same as unkeyed amp with tube Removed. Continue to move meter switch to current ranges..no idle current 150/200 indicates that the 3 500Z is the shorted proublem...D117 is also the meter protection diode and the 2 small caps beside often fail together (tube arking inside, tube short's ,to lite of loading control can cause arcking inside tube and tank stage. B+ is on tube at standby or operate, "operate switch" controls the bypass relay remote key line and with tube removed the procedure will help pin down what often is a internal tube defect that is a shorted 3 500Z.
KC7QNM, Apr 28, 2011
Any updates?
rgg
