F6 Illustrated Build Guide

I think I will be using an XLR connector. Probably a 4 or 5 pin version so I don't inadvertently plug in a 3 pin XLR.
That probably will not have the current capacity you need. A Neutrix PowerCon would work fine. It is pulling a few amps continuously fro the PSU.

Also putting some of the PSU capacitors in the amp box would be good, that will help alleviate the issues of the separate chassis with the extra power cable's inductance and resistance etc.
 
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I can use some help please.
I have no smoke (good) or voltage across R2 (bad).
Does a voltage, current, and resistance test point matrix exist for the F6?

Thanks,
-Bill
 

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@bbm3 - Hang on! I rarely chime in with my lack of knowledge, but I assume you've checked your PSU voltages. If not, do that before changing anything. The wiring specifically related to the CL-60s and primaries looks OK to me based on a standard dual primary Antek transformer and 120VAC mains, but I may have missed something. Looks like your CL-60s are wired between the two hot and two neutral per the schematic for 120VAC mains. That doesn't rule out everything, but again, I assume you checked your PSU. If you have, then move on, if not stop and wait if you're not 100% sure of what to do next based on mine and previous comments.

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If you've checked your PSU.

I don't know of a reference schematic with expected voltages / currents.

I don't see any stuffing errors on the amp boards, but some areas are not clear in the pics, and my eyesight is not wonderful.

Have you turned P2? Did you intentionally turn P2 all the way or partially one direction before installation b/c of the notes in the build guide that bias may be too high at P2 mid-point?

I'd wait for others to chime in, but if my PSU was working properly, and if I had checked my amp boards for obvious stuffing errors and used a DBT to check for shorts; I would turn P2 until Q2 turns on indicated by seeing voltage across R2. I'd start with clockwise. If I didn't see it turn on when I turned P2 in one direction, then I'd turn it the other. If the pot went to max turns in both directions without any current (or not enough) through R2, I'd report back. Depending on the level of success, zeners and/or values for for R11, R12 may come up.

Note - I am a novice, but that's what I'd do. I'm not in the FAB club yet, and I may have it wrong, but I think it's low risk. Lower risk is waiting for a more experienced member or moderator to chime in and say that I'm a dodo and lay out a more clear path. :D
 
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Thank you for the feedback. I did indeed mis-wire the CL60. I did check everything from the wall to the power supply outputs one stage at a time before energizing the next.
Everything is working correctly now.

Thanks for everyone”s help.
 
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It did work the way I had it but the CL-60 was only limiting one input. I tied Both red leads together and both black leads together and removed the CL-60 on the neutral side much neater and how it should have been.

The real problem is I had to turn P2 way more than I expected in order to begin seeing voltage across R2. Now I have P2 turned to the limit and I am only seeing 2.45V. I will move on to offset and watch what happens to the bias.
 
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Thanks for that! Truly appreciated. I love to learn from these threads.

#1 doesn't track with me, but that's clearly due to my lack of knowledge. I'll ponder, observe, study the schematics again, and hopefully learn.

#2 tracks completely with my limited understanding and was what I was alluding to re: potentially not enough current through R2 => Bias at Q2 => Maybe Zener / R11 / R12 adjustment depending on your particular results. Again... just noodling. One thing I've learned is that if I post something completely ignorant, a number of helpful people will jump in to correct it. :)

Either way, I'm happy that it seems to be going according to plan. Sorry if I derailed progress. :)
 
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No apology!
I”m totally new to this too. Well at least using a linear power supply.
I built a pair of Amp Camps, a couple B1’s and some simple chip amps but this has many new challenges for me.. Thanks for looking over my shoulder as we learn together..
I’ll keep you posted if you like.
Thanks again for the help.
-Bill