DX-100B Problem

[Dennis Heikura]

Hi Gang,

Have a nice DX-100B that has me stumped. Rig shows excellent grid drive
but will not load. Cannot get plate current much above 40 ma and power
out
more than 10 or 15 watts. Plate shows nice even dip. Have tried
everything
I can think of including:

    Clamp adjustment
    Different finals
    Checked for shorts in tank circuit.
    Removed RF sub chassis and soldered 6146 sockets directly to chassis
to
      improve grounds.
    Checked bandswitch wireing.
    Disconnected and bypassed 160 meter coil.
    Counted turns on tank coil and compared with a known good rig.
    Voltage checks are all ok. (Plate and Screens.)
    Replaced bypass caps on 6146s.
    Replaced Clamp tube.
    Replaced Driver.
    Substituted plate RF choke with one from SB-102. (Rig went into
       immediate oscillation when turning on plate voltage. Plate
current jumped to
       over 300 ma instantly. Quickly turned of plate voltage.
    Replaced SO-239 connector. (Thought it may have a high resistance
short
        to ground for RF.
    Replaced plate blocking capacitor. (Was originally shorted when got
the rig).

Two knowledgible friends have helped me with this monster and all of us
are at
a loss. RF is evidently going somewhere but where. Tank components
exhibit no
unusual heating as one would expect to see if RF was shorted etc.

Anyone else ever see this? All help would be greatly appreciated. Would
really
like to get this unit up for 160 meter AM operation this winter.

73 and thanks for the BW,
Denny==WB7EGG/6

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