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Old 12th June 2011, 12:26 PM   #11
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Quote:
Originally Posted by buzzforb View Post
Do you see the R100 as being a better transistor or just easier to work with?
I say it was just easier for that specific issue. It seems finicky to me, because I don't understand it's 'sweet spots'.

Last edited by Tea-Bag; 12th June 2011 at 12:38 PM.
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Old 12th June 2011, 01:37 PM   #12
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One thing i have noticed on most of Nelson's articles, is that he always seems to start using the different transistors in simple topology's. He finds the sweet spot for that particular transistor and then builds out the topology based on those findings. I know it would require more tweaking but it seems to be a plausible way of doing things. Perhaps it is just done that way in his articles for the sake of walking learners through the process.
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Old 12th June 2011, 04:50 PM   #13
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I like to try different transistors in the same old circuits. Occasionally
you get a little surprise.

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Old 12th June 2011, 05:57 PM   #14
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the above phrase 'occasionally you get a little surprise' is one of those glass half full/empty comments
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Old 12th June 2011, 06:54 PM   #15
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The R100 in ZV4 or R085 in F3. The F3 with buffer like ZV4. The possibilities are endless. THat is where the problem lies. R085 in F3 may allow for higher power F3 without too much complication. Even the PLH looks interesting with SS fets.
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Old 12th June 2011, 07:27 PM   #16
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Well, the slow start of F3, higher voltages and current source make me want to try it out. Nelson has left a few crumbs with delite and ArchNemisis to get some ideas.
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Old 12th June 2011, 08:03 PM   #17
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I will build the F3 and then hopefully substitute the R085 in and see what happens. IF you have not seen it before, Vladimirk has a nice thread on a higher power ZV9. I have been thinking about ways to get rid of the output caps. Dual rails will do it, but seems difficult to implement with DM fets.
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Old 12th June 2011, 08:37 PM   #18
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Old 12th June 2011, 09:18 PM   #19
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Hoping to keep non balanced setup to retain the second harmonic signature. Not sure if that means anything yet or not.
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Old 12th June 2011, 10:23 PM   #20
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Quote:
Originally Posted by buzzforb View Post
...IF you have not seen it before, Vladimirk has a nice thread on a higher power ZV9. I have been thinking about ways to get rid of the output caps. Dual rails will do it, but seems difficult to implement with DM fets.
Dual rails will force you to use an input cap and suffer gain of the power supply noise, hum etc. etc. Your input would need to be refrenced to the source of the JFET which is the -rail. The actual input signal will not have this noise, hum signal so it will become part of the signal path and be gained up by the circuit. Stcking with the output cap might be better...
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