Atilla,
Great looking build. I'm curious what current your running at and how hot those sinks get on the MOSFET's.
Great looking build. I'm curious what current your running at and how hot those sinks get on the MOSFET's.
I ended up running 116mA and 122mA, with 3x51ohm resistors. Last time I measured the heatsinks, after running them in the completely sealed case, they were 65-68 degrees. In open air they run at around 45 degrees I believe. They're surprisingly effective. After punching a few small holes in the case, for some basic air circulation, I'm guessing they're somewhere around 50, maybe even lower. Completely sealed cases aren't good for you 🙂
I wish I'd go over 250mA, but I'll leave that for the second board and some proper heatsinking. Not to mention this trafo wouldn't cope with that anyway.
I wish I'd go over 250mA, but I'll leave that for the second board and some proper heatsinking. Not to mention this trafo wouldn't cope with that anyway.
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Yes / No 😀
(but compared to commercial offerings, it is cheap, and sounds better than anything you can buy)
Arne K
Hi Salas
I'm currently hotrodding a blk Hypno board using 2 x 20 ohms/2 W resistors (after 30 min body temp 47°)
VDC in 16.96/16.96, R1 drop 2.21/2.19 V, VDC out +10.47/- 9.92 V
CCS Mosfet cases reached a temp of about 31-32° (lid open, ambient 22°), meaning that my homebrewed heatsinks work (they become barely warm).
2 questions:
There's any real advantage to go further? I mean dropping a bit more R1 value? I read something about 8.2 ohms..... I might add a third 47 ohms resistor. The recifiers are 1.1 A Schottky and the Xfrm is a 12+12 VAC/48VA
Should I also connect the 2SK170 in the positive Vref CCS in the "orthodox way" (GS tied instead of GD) as in the new Hypno Blue Edition? I'm using a Wima MKP2 0.22uF for Vref leds bypassing.
Thank you!
I'm currently hotrodding a blk Hypno board using 2 x 20 ohms/2 W resistors (after 30 min body temp 47°)
VDC in 16.96/16.96, R1 drop 2.21/2.19 V, VDC out +10.47/- 9.92 V
CCS Mosfet cases reached a temp of about 31-32° (lid open, ambient 22°), meaning that my homebrewed heatsinks work (they become barely warm).
2 questions:
There's any real advantage to go further? I mean dropping a bit more R1 value? I read something about 8.2 ohms..... I might add a third 47 ohms resistor. The recifiers are 1.1 A Schottky and the Xfrm is a 12+12 VAC/48VA
Should I also connect the 2SK170 in the positive Vref CCS in the "orthodox way" (GS tied instead of GD) as in the new Hypno Blue Edition? I'm using a Wima MKP2 0.22uF for Vref leds bypassing.
Thank you!
With R1 being 10ohm, and drop being 2.20, you're running 220mA current trough the CSS MOSFET. IIRC, 200-250mA was the first point where you get benefit, 1A being the next.. Scratch that, see Salas below.
As Rod Elliot wrote - "They like to run hot" (and that's highly biased, not deliberattely frying them). Unless you want to really boost the current you've got right now, there might be little point in increasing it. And you'll need to boost your rectifiers and your transformer at one point. Am I correct in this - the info was spread over many threads, and I can't find the posts for reference right now.
That being said, a little more current won't hurt you. I am perfectly happy with 120mA though.
As Rod Elliot wrote - "They like to run hot" (and that's highly biased, not deliberattely frying them). Unless you want to really boost the current you've got right now, there might be little point in increasing it. And you'll need to boost your rectifiers and your transformer at one point. Am I correct in this - the info was spread over many threads, and I can't find the posts for reference right now.
That being said, a little more current won't hurt you. I am perfectly happy with 120mA though.
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Massimo:
Go up to 300mA its a good point. Then is 600mA-1A, i.e. really high. In high current the orthodox can be nice, try it subjectively. It can change your DC offset a bit, will get the V+/- closer.
Go up to 300mA its a good point. Then is 600mA-1A, i.e. really high. In high current the orthodox can be nice, try it subjectively. It can change your DC offset a bit, will get the V+/- closer.
thank you again.Pics will follow: wrong day today, rain, not enough light. Bright sun in Athens (and 19°) isn't it? 😉
Salas, by the way, what is your reference for those currents? I'd like to know more. I've got another board to build and I intend to run it at higher current.
OK, I'll go for 3 x 20 ohm (don't have any other suitable value handy), a bit more than 300 mA, but not more.
I mind the polar bear 😉
I mind the polar bear 😉
I am looking for a symmetrical +/- 19V PSU for an I/V stage. Can I use this board, leaving out the B1 bit?
(sorry, I remember somewhere reading it was not possible, and somewhere that it was... I got lost in the different versions)
(sorry, I remember somewhere reading it was not possible, and somewhere that it was... I got lost in the different versions)
Please bear with me as i am quite new to all this.
There is a group buy going on, for two versions of the B1. The hot rod Hypno and the Mezmerize.
I would like the Mezmerize board because of the multiple inputs. But i see that there is not a lot of interest so there is a chance, the Mez will not ship.
So the other option is the Hypnotize which offers one input one output.
My possibly silly question is :
Assuming i have the Hypno board, if i feed the input from rca to a selector ( or relays ) then from the selector ( or relays ) to a pot and then from the pot to the boards input, wouldnt that work?Wouldnt that make it multiple inputs? Is it wrong? Is it not wrong but not suggested?
Thanks for any feedback.
Michael.
There is a group buy going on, for two versions of the B1. The hot rod Hypno and the Mezmerize.
I would like the Mezmerize board because of the multiple inputs. But i see that there is not a lot of interest so there is a chance, the Mez will not ship.
So the other option is the Hypnotize which offers one input one output.
My possibly silly question is :
Assuming i have the Hypno board, if i feed the input from rca to a selector ( or relays ) then from the selector ( or relays ) to a pot and then from the pot to the boards input, wouldnt that work?Wouldnt that make it multiple inputs? Is it wrong? Is it not wrong but not suggested?
Thanks for any feedback.
Michael.
Omit output relay?
I don't have the necessary relays on hand and my amps already have a relay-delayed start on their outputs.
So I reckon its safe to bypass the relay in this case. Please confirm that the B1 does not emit some type of amp-killing signal when power is first applied.
I don't have the necessary relays on hand and my amps already have a relay-delayed start on their outputs.
So I reckon its safe to bypass the relay in this case. Please confirm that the B1 does not emit some type of amp-killing signal when power is first applied.
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