[Johnson] Start of New Year

David C. Hallam dhallam at knology.net
Thu Jan 1 09:25:13 EST 2015


I looks like I have a major project on my hands.  My Invader 2000 gave 
up yesterday and has no output.  My first guess is the amp output 
circuit.  The driver loads properly and the finals draw current as 
indicated on the grid, screen and plate meters.  But, there is no 
indication of output.  Plate voltage and the zero signal plate current 
are OK The antenna system is OK as the receiver works but I will check 
out the coax change over relay first.  Beyond that things get difficult.

I do not have 240V at my garage workshop and the Invader is too heavy 
for me to move anyway.  Just had arthroscopic surgery on my shoulder.  
At 60+ lb for the transmitter and 100+ lb for the power supply I 
couldn't manage it anyway.  I have to completely tear down my operating 
desk and move test equipment in from the garage.  Not a happy start for 
the new year.

David
KW4DH

-- 
There are two possible outcomes: if the result confirms the hypothesis, then you've made a measurement.
If the result is contrary to the hypothesis, then you've made a discovery.
Enrico Fermi



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