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Newer page: version 6 Last edited on April 22, 2021 2:42 am. by
Older page: version 5 Last edited on April 19, 2007 7:38 pm. by
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 See ''Zapping'' below for an easier (but not 100% reliable) alternative to physically cleaning the percussion switches. 
  
 * Remove the music rack, the two large screws and two wood screws which secure the drawbar base, place heavy paper (or thin carboard) at either end to avoid scratches and raise the drawbar base 4 to 5 inches. (See also HowToRaiseTheManuals.) 
  
-* Remove the two screws from the percussion switch cover and remove it. Spray the interior of the percussion switch housing and contacts with a good non-residual cleaner and retest to see if it works. 
+* Remove the two screws from the percussion switch cover and remove it. Spray the interior of the percussion switch housing and contacts with a good non-residual cleaner and retest to see if it works. Line the inside of the cover with an insulating tape . 
  
 ;: As only about 1/2 of the contacts are reachable from the back of the switch, it may be necessary to dismantle the entire switch to get results. This is not a job for the faint of heart. Many foul words have been uttered during re-assembly. Some will advise applying copius amounts of D.C. to burn the ofending bits into oblivion. I don't recommend this procedure as severe damage to many components may occur. 
  
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 comments. 
  
 You have several choices of where to zap: 
  
-# To zap the upper manual assembly, unsolder the white wire from the B preset bundle at the ResistorPanel. Select the B preset, and zap between the white wire and the manual chassis (ground). This will flash away dendrites only in the manual assembly and will not affect any dendrites that might be in the percussion switches. 
+# To zap the upper manual assembly, unsolder the white wires from the B preset bundle at the ResistorPanel. Select the B preset, and zap between the white wire, that runs to the manual, and the manual chassis (ground). This will flash away dendrites only in the manual assembly and will not affect any dendrites that might be in the percussion switches. 
  
 # Unsolder the blue wire from the K terminal on the preamp. Rock the percussion switches (all four) toward the player and flash between the blue wire and ground (the preamp chassis). Rock the percussion switches away from the player, and flash again between the blue wire and ground. 
  
 # It can also be beneficial to flash the other percussion-related wires on the preamp terminals. In particular, in one case where the percussion disappeared only when the decay was set to "slow," flashing the H, J, M, and N wires (unsoldered) with the switches in both positions solved the problem. 

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