Is it wrong in F5 TURBO V3?

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As Itsmee says, and N.P, "In the example of cascode Q7, a voltage reference is set by resistors R25 and R27 between V+ and Ground so that the Jfets see about 1/3 of the rail voltage." In order for "them" to see 1/3 the rail voltage, yes, R26 would be about 10k!
 
this is a good example of how important it is to try to understand how the circuit actually works over just building it. If you are going for a one shot deal, I can understand just putting it together, but if you want to continue on in building different things, try to look beyond the values and into the circuit and understand why they are there and what it is that they do. I have often found deep satisfaction in finally understanding what others may consider trivial. For me it is another life/learning experience.
 
this is a good example of how important it is to try to understand how the circuit actually works over just building it. If you are going for a one shot deal, I can understand just putting it together, but if you want to continue on in building different things, try to look beyond the values and into the circuit and understand why they are there and what it is that they do. I have often found deep satisfaction in finally understanding what others may consider trivial. For me it is another life/learning experience.

There are people who understand the circuits and the role of each component very well and would like to experiment and then there are some like me who understand basically and superficially at a block level and cannot go beyond that, not for lack of application but due to certain limitations. For me lack of complete understanding does not prevent me from building. I hope these builds work and if it does not - seek help from forum members and see where it ends up. I would rather try and fail, than not build anything at all. Different strokes for different folks...
 
Have you gotten the non working channel up and running? Any firther ideas of what might b wrong or measurements to help guide members.

BTW, how do you like your Altec onken's. I have a pair of 416a's and 288's waiting for my lazy butt to do something with them.

Thanks. I completed passive measurements of comparing both the channels for PCB continuity as well as component integrity (barring few which cannot be tested by DMM). Everything looks fine after fixing 2 dry solders and one bad connection on P1's centre leg. I have just mounted the board back on the heatsink with other mica+goop paraphernalia. I will power it back and see where it goes. I do have a spare board with components if I cannot trace the problem further. It's been difficult juggling time between family, work and hobby.

I have Altec Onkens built around 515Bs and HF 808's through 811B sectoral horns. They are terrific - driven active by a pair of F5s. Just received Azura horns to be paired with existing 288s. Should be good. Closely following Beyond Ariel. I do have 416As as well.
 
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