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Old 11th March 2013, 05:43 PM   #1061
6L6 is offline 6L6  United States
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So a cascode on top of the front end to keep the Jfets from frying, and what else?

Sounds interesting.
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Old 11th March 2013, 05:57 PM   #1062
Zen Mod is offline Zen Mod  Serbia
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no frying , no Herr Mueller , sweetspottier

read F3 article
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Old 14th March 2013, 12:03 AM   #1063
rade95 is offline rade95  United States
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Quote:
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no frying , no Herr Mueller , sweetspottier

read F3 article
Zen Mod what is your point? I read F3 and ZM #8 articles. I am not talking about SE Class A JFET/MOSFET amp, but PP Class AB amp. To my knowledge FW hasn't designed such an amp yet, PassLabs did, several in fact. If I missed FW design or if this has been discussed in some other FX threads, pls point me to the thread, but F3 or ZM #8 is _not_ what I am looking for.
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Old 14th March 2013, 02:42 AM   #1064
Zen Mod is offline Zen Mod  Serbia
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cascoding , same as modulated cascoding , is covered in FW F3 article

I was replying to 6L6 , without seeing that his post is more reply to your's , then general question

whatever - idea about lighter biased F5 is covered already , somewhere in F5 threads
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Old 14th March 2013, 03:13 AM   #1065
rade95 is offline rade95  United States
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No problem, if you can point the page where this was discussed I would appreciate it. I want to have a lower bias but higher +- rails, that would make MOSFETs work in class AB switched mode, producing more power. I doubt that this can be done without having a new driver stage.
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Old 20th March 2013, 09:32 PM   #1066
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Stupid question, but its taking me way to long to search up the answer:

Where on the schematic does r35 and the led go? Can i use any led and a 50k trimmer pot to adjust the light to my taste? I like them dim. Im making my ft p2p wired, and the picture of the board tells me to little.

Also the original schematic differs quite a lot from the one in the store now. What are the big difference in functionality?

Again, I know these questions are stupid, there is just to much irrelevant information out there.


Thanks!
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Old 20th March 2013, 09:53 PM   #1067
Zen Mod is offline Zen Mod  Serbia
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yup - led and trimpot will do - connect it between any side of PSU and gnd ;

regarding differences between F5 origigi and store pcbs - search for Cviller's blog
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Old 20th March 2013, 10:37 PM   #1068
labjr is offline labjr  United States
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Originally Posted by Jallhalla View Post
Stupid question, but its taking me way to long to search up the answer:

Where on the schematic does r35 and the led go? Can i use any led and a 50k trimmer pot to adjust the light to my taste? I like them dim. Im making my ft p2p wired, and the picture of the board tells me to little.

Also the original schematic differs quite a lot from the one in the store now. What are the big difference in functionality?

Again, I know these questions are stupid, there is just to much irrelevant information out there.


Thanks!

There's even another different F5 schematic in the F5 Turbo manual which I think is the latest version.

Pot. P3 is added to tweak input symmetry for lowest distortion.

The input resistors R1&R2 are new values and configured differently. Thermistors TH1&TH2 are not connected to the rails. Not sure what those changes accomplished. Probably subtle differences.
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Old 20th March 2013, 10:49 PM   #1069
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TH1 and TH2 is connected to the other side (after) source resistor. insted of before source resistor.
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Old 21st March 2013, 12:47 AM   #1070
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That is what Im talking about. Why are we doing this? Have searched for a while now. The blog only mentioned the cascoding and more output mosfets. Im bulding the standard first.

Do you know any place in trondheim to get sheet aluminium and aluminium angles, by the way?
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