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Quad 833 progress



Original poster: "Sundog by way of Terry Fritz <twftesla-at-qwest-dot-net>" <sundog-at-timeship-dot-net>

Hi All
    Tinkered with the coil for about 4 hours tonight, and learned a lot about
suppressing parasitics and exactly how much noise 5" of 1/4" copper strap can
put into a signal :) 
 
  To make a long story short, here's what I found.
    
    Non-inductive resistors work best (duh ;), and the ferrite cored choke from
the magnetron works *much* better than 20 turns of 20ga wound on a pencil.  The
grid is responsible for 90% of the hash in the plate's output, and with a good
RL filter on the grid, I could run with no filter at all on the plate and could
spot only minor interferences in the waveform.  
    I had the secondary removed and used 6 turns of 12ga THHN with a light bulb
across it to load down the coil (man that works excellent! Thanks Rob!)  The
closer the RL filter to the grid the better the suppression is.  
 
  All in all, a very informative evening, and best of all, I could run the coil
up to about 80% input power (limited to 800w right now) with no radio
interference or TVI. At that power level the load lightbulb was glowin' really
bright (whooman that's neat!).  But, it's about midnight, and I'm gonna put it
all away for the evening.  Tomorrow I'll build the RL filters for the other
bank of 833's and start testing it out on that side.  We'll know more by sunday
night. :)
---------------------------------
Shad (Sundog)
G-1 #1203