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debugging sweet thing (jfets)
 5/11/2000 12:07 PM |
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Ed Guidry | debugging sweet thing (jfets) I etched a new board, the old board looked kind of "iffy" where I had to scratch out traces that shouldn't have been. Swapped the components over and....nothing. Looked it over thoroughly, looked fine. However, the voltages were definitely not right. When the plug is in and the ground connection is made, nearly all of the points on q1-q4 have continuity with the meter. In addition, R3 is developing some heat. That can't be right.... Here's some voltages again, maybe someone can figure it out. The voltages are listed in order of gate, source, drain. Q1: 4.83v 4.73v 5.73v Q2: 5.76v 5.70v 6.68v Q3: 4.73v 4.64v 5.66v Q4: 5.71v 5.66v 6.63v Q5: 2.82v 3.29v 6.59v Now, I buzzed around with the meter without the plug grounding out the battery. Everything seemed to be okay, no shorts anywhere, the source of Q1 did buzz to ground, and the source of Q3 buzzed to ground (only when drive pot was maxed) Which seems to make sense, there's only 100 ohms resistance to ground at those spots. |
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| anonymous Minibooster voltage readings are ty... -- 5/11/2000 1:13 PM Doug Another thing, Ed. Don't mean to ni... -- 5/11/2000 4:25 PM |