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What a darn nice looking pcb, I would have been very proud to have been able to show something like that.
Kind of "long". If he broke it in 2 parts (voltage stage/OPS) and stood the voltage stage up on end it would fit in half the space.
Krisfr ,Much better work in a such a short time.
OS
This amp will not do TMC (well), the VAS is essentially a differential... the TMC error "pulses" will basically cancel out and a nasty spike will appear in the bode plot in this case. TMC "likes" a single ended super high OLG amp (110-120db) with a rock solid CCS (ax). I don't want to see you do as I did and make a "dud" for your "goldmund killer".
My EX is basically the original goldmund with MJE340/350's for the VAS. I took the 2 beta enhancements out of my failed amp and tweaked it to perfection. Since no one has actually built this yet except me , be prepared to jumper your beta enhancement trannies. You can (almost) get the same OLG by using BJT's for the input pair instead. I did not experiment much with the fet's so who knows ??? I reached the conclusion to "keep it simple" and ended up with basically the original goldmund. BTW , I ran the EX on a pair of the original mosfet outputs (to-3) ... they sounded great.
OS
Thanks Guys for all the input...
I am getting tired right about now.
I etched one, after I botched the first two by not applying enough heat. So I cleaned them off, and reapplied some HEAT...
Cleaning off the paper and will etch them before the night is out.
I inserted the last recommendations too. I do not have to put in the TMC componets so it is not a big deal, but it was better to have and not need etc.
It is going to take time to get these up and running, slow but sure as with anything totally new...Maybe I will learn something while doing all of this, I hope so, so I can share back to you guys...
I am getting tired right about now.
I etched one, after I botched the first two by not applying enough heat. So I cleaned them off, and reapplied some HEAT...
Cleaning off the paper and will etch them before the night is out.
I inserted the last recommendations too. I do not have to put in the TMC componets so it is not a big deal, but it was better to have and not need etc.
It is going to take time to get these up and running, slow but sure as with anything totally new...Maybe I will learn something while doing all of this, I hope so, so I can share back to you guys...
The best learning comes from doing. Or that's the way it is for me. I learn plenty, especially from my frak ups. 🙂
With a couple of small blemishes
I am done for the night...
Tomorrow starts with tinning, thanks to John😎
I am done for the night...Tomorrow starts with tinning, thanks to John😎
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Coming from you that is a Real Compliment 😀Nice!
But you had input into all of this for me😛
Thanks
and Especial for Alex...
With a couple of small blemishes
Tomorrow starts with tinning, thanks to John😎
Very nice (material) , and etch. Is that the same CEM-3 you gave me? Built like plywood , the traces are nearly impossible to burn off ... 2 oz. Killer stuff. You be a [man of action -tm] .. too !!
OS
Yep, same MO Works like a charm...😀
Maybe Keantoken can take advantage of me and get one of these with the Suface mount LSK389a on them. They where shipped from Linear 2 days ago. They are nice folks😎
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Hey guys. Nice work Krisfr!
I feel stupid not getting a prototype running in all this time. I wanted to do a p-p prototype above a blank PCB for ground connections. I do have most of the parts, but I wonder what on earth happened to TechDIY. I guess since I have the money now would be a good time to go to profusion and get the TO-3 devices to fit in the heatsink I already have. I was wanting to get the original 2SK/J devices though since they were what the design was meant for.
I'm curious if anything could be gained by using carbon comp resistors in the right places, IE gate stoppers (a paper I read said instability was proportional to the gate inductance, and a film resistor could add as much as an effective inch of wire).
- keantoken
I feel stupid not getting a prototype running in all this time. I wanted to do a p-p prototype above a blank PCB for ground connections. I do have most of the parts, but I wonder what on earth happened to TechDIY. I guess since I have the money now would be a good time to go to profusion and get the TO-3 devices to fit in the heatsink I already have. I was wanting to get the original 2SK/J devices though since they were what the design was meant for.
I'm curious if anything could be gained by using carbon comp resistors in the right places, IE gate stoppers (a paper I read said instability was proportional to the gate inductance, and a film resistor could add as much as an effective inch of wire).
- keantoken
complete alu option http://www.modushop.biz/ecommerce/cat145_l2.php?n=1
covers with dissipation holes standard
mind you, 4U and 5U alu seem to cost the same
which makes 5U alu attractive
My bad, you're right about the back, but other 4 panels are 2mm steel.
I've seen these cases in person and they are good, but 2mm doesnt shield much, especially if with holes.
I was referring to these which have also the back of steel:
modushop.biz
Anyway, there is little alternative, unless you build yourself using a cnc machine.
I've seen these cases in person and they are good, but 2mm doesnt shield much, especially if with holes.
I was referring to these which have also the back of steel:
modushop.biz
Anyway, there is little alternative, unless you build yourself using a cnc machine.
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are the steel panels that thin?
0.1mm ~ 4thou ~ 4mil ~ 0.004"
0.2mm ~ 8thou ~ 8mil ~ 0.008"
its good you noted that the standard version have steel panels
people may not notice before buying
tho, alu version have all panels in 3mm aluminium
from memory, 3mm alu is quite strong
but I do think its more a question of stability, rather than shielding
a big toroid can be heavy
might consider additional reinforcement