Congratulations on your complete amplifier!
I must agree with the other posters, your case is very attractive and has a balance and proportion that is very harmonious.
I must agree with the other posters, your case is very attractive and has a balance and proportion that is very harmonious.
Great build---- lovely work and vision. Someone once said, "A laborer works with his hands; a craftsman with his hands and mind, and an artist with his hands, mind and heart." Jpedro is an artist.
Jeff
Jeff
Dear, vdi_nenna, 6L6 and jeffharr.
Thank you. I am encouraged by your words the appreciation
Thank you. I am encouraged by your words the appreciation
Excellent construction.
Case is very unique and appealing.
You have a good sense for the drawing and style.
Thanks for sharing.
Case is very unique and appealing.
You have a good sense for the drawing and style.
Thanks for sharing.
Carlomar,
Thank you for your support and technical advice.
Were fundamental for the good success of the project.
Thank you for your support and technical advice.
Were fundamental for the good success of the project.
Anyone know if the F5 clone boards in the store have been updated with P3 and other changes in the circuit? The schematic in the store shows P3 but it doesn't appear to be pictured on the board.
Well, here's my latest F5 in operation -- I now have 8 F5's in operation including some for which I did the PCB's by hand -- this version has some stuff I've found necessary or helpful over the years -- I provisioned parallel surface mount JFETs -- pairs of mmbf5460/mmbf5457 which get you close to the J74/K170 and are very inexpensive -- P3 is there of course as well as mounting holes for paralleling in various source resistors.
I put some local capacitance on the board -- when testing these amplifier with long leads you invariably get some oscillation. The RFI mitigation cap and output zobel aren't strictly necessary until they become necessary.
I constrained the board dimensions so that it would fit in the chassis/cases which the DIYAUDIO store is offering, although I roll my own.
I put some local capacitance on the board -- when testing these amplifier with long leads you invariably get some oscillation. The RFI mitigation cap and output zobel aren't strictly necessary until they become necessary.
I constrained the board dimensions so that it would fit in the chassis/cases which the DIYAUDIO store is offering, although I roll my own.
An externally hosted image should be here but it was not working when we last tested it.
My F5 will be a stock one in first time... Tweaks will come after if necessary.
Transformers will arrive tomorrow, I have ordered two 300VA 2x18V, one for each channel 😎
Damien
Transformers will arrive tomorrow, I have ordered two 300VA 2x18V, one for each channel 😎
Damien
I wanted to add P3 to my project. I'm a little worrried about causing extra noise, oscillation etc. if the pot is too far from the input FETs.
Here's the schematic to go with the revised board:
An externally hosted image should be here but it was not working when we last tested it.
The changes to the F5 circuit are in the F5 tubo manual. I just figured they are the latest therefore they must make it better.
John,
I see you haven't included the provision for the small value gate stopper resistors (47R & 68R) and filter capacitors on the input jfets, as in your early design with the double sided board?
Did you find these additions to be counter productive?
Is it possible to line the power resistors up "sideways" to attach the Caddock style (TO220/247 packages) power resistors to a common heatsink thru the centre of the board?
And perhaps adding a Cmultiplier/simple zener regulator onto the ends of the board with room for 25mm power supply caps?
I see you haven't included the provision for the small value gate stopper resistors (47R & 68R) and filter capacitors on the input jfets, as in your early design with the double sided board?
Did you find these additions to be counter productive?
Is it possible to line the power resistors up "sideways" to attach the Caddock style (TO220/247 packages) power resistors to a common heatsink thru the centre of the board?
And perhaps adding a Cmultiplier/simple zener regulator onto the ends of the board with room for 25mm power supply caps?
Good idea. The way i have it setup is as a voltage divider for no useful reason! My bad.