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previous: Scott If you have access to a scope, watc... -- 11/23/1999 5:15 PM View Thread

Re: Pesky parasitic or ? ...... the Twin (again)

11/23/1999 5:43 PM
Rob W.
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Re: Pesky parasitic or ? ...... the Twin (again)
Also if it is oscillation, try putting a cap across pins 1 and 6 of the phase inverter tube. (12AT7, V6)  
Try a 100pF first, and see if the noise goes away. This cap cuts out high end, and oscillation. This was commonplace on Tweed and Brown Fenders. This cap will darken the tone a little, but some like it.. (You can go basically anywhere between 47pF and 250pF, of course the higer you go - the more treble loss)  
 
If this cap eliminates the noise, you have oscillation.  
 
Happy Tinkering!  
Rob W.