Ultimately, the feedback loop is tuned for stability and performance with the PA774 output transformers, and the Edcor's need to be separately tuned. I hope to do that this year - a full Edcor setup - when I mess with the Rev EFB. In the meantime, I would see if you get a greater margin of stability with the NFB pot adjusted for something in the 30K to 40K range. I'll get those picture links to you tonight. Look sharp!
Shannon
New ST-35 unstable
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by Shannon Parks » Mon Jan 30, 2012 4:43 pm
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Shannon Parks - Site Admin
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by apurcell22 » Tue Jan 31, 2012 2:30 pm
Ok guys
Here is an update. I put the 6p14p-ev tubes back in, and ran the amp for several hours. I just checked, and the amp is nice and stable. I guess that all that was needed was a bit of burn in time. All this time I figured that I had screwed something up! Who'd a thunk it? Burn in is real!
Al
Here is an update. I put the 6p14p-ev tubes back in, and ran the amp for several hours. I just checked, and the amp is nice and stable. I guess that all that was needed was a bit of burn in time. All this time I figured that I had screwed something up! Who'd a thunk it? Burn in is real!
Al
- apurcell22
- Posts: 57
- Joined: Mon Apr 12, 2010 7:17 pm
19 posts
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