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FS: First Watt F7 clone assembled boards

I have a pair of First watt F7 boards, designed by me, and power supply with 12 capacitors.
The schematic is based on simulation and tips and hints from forum members, you can read in First Watt F7 review thread.
The boards are symmetrical and can accept another pair of output transistors to make it a Turbo version.
The output transistors are Exicon lateral Fets.
Compare to original I added some decoupling electrolytic capacitors on the board, to further reduce the noise. I have bare boards also if interested
This sound very good so I have built 2 of these, in fact this is the best sounding First watt amplifier in my opinion, mostly because it has the highest dumping factor of all, 100.
The bass is amazing compare to the others, and I have built a lot like F3 , F5, F6 etc.
If you want to try an F7 now is your chance.
 

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Last edited:
I have a pair of First watt F7 boards, designed by me, and power supply with 12 capacitors.
The schematic is based on simulation and tips and hints from forum members, you can read in First Watt F7 review thread.
The boards are symmetrical and can accept another pair of output transistors to make it a Turbo version.
The output transistors are Exicon lateral Fets.
Compare to original I added some decoupling electrolytic capacitors on the board, to further reduce the noise. I have bare boards also if interested
This sound very good so I have built 2 of these, in fact this is the best sounding First watt amplifier in my opinion, mostly because it has the highest dumping factor of all, 100.
The bass is amazing compare to the others, and I have built a lot like F3 , F5, F6 etc.
If you want to try and F7 now is your chance.
$?
 
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Reactions: mordikai
If you have the F7 amplifier + power supply boards, what other components would you need (other than chassis/heatsink + power transformer) to complete this kit?
If case doesn't have them, you need binding posts, RCA input connectors, power switch, hook up wire, and 2 CL60 thermistors to limit the inrush current from transformer. Or a soft start module better.
 
Doesn’t one need a scope to appropriately set up the F7 circuit? I was under the impression that more skill was needed to build the F7 clone compared to F5, M2, Aleph J, etc.
You only need a scope if you want to set exact ration of H2 to H3 distortions. That can be done by listening also. I found is not that critical. The setup for this amp is the same as F5. In fact F7 is an F5 with positive feedback. Read F5 builders thread for more info. This is not the place for that.
 
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Reactions: von Ah
Now I have only bare boards the green ones I posted, they are not symmetrical they are for left and right channel, they are more like the original F7
For the power supply I have two types, first one is for a single transformer and second one is if you have 2 transformer one for each channel in a dual mono configuration. Price is $20 Usd for the amp boards and $10 for the power supply, plus shipping.
If you need assembled boards PM me, I still have parts for one set, except power supply.