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Old March 15th, 2008, 08:46 AM   #528 (permalink)
reddart
TDPRI Member
 
Join Date: Dec 2007
Location: Upstate NY
Posts: 27
Quote:
Originally Posted by Jaybird View Post
In the past I have wired OTs backward by mistake and the squeal began immediatly. In the present problem, the squeal does not occur until the 47k NFB resistor is connected.
The squeal in the past is probably because there was already NF in the circuit...if there is no NF, then it doesn't matter what the phase of the OT is (in terms of NF induced squeal, at least). Your symptoms still look like an positive feedback issue...until you actually try it and prove it false, I'm not convinced...
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