I am talking about Fischer SK 109 heatsinks with alu plates to make a windtunnel (they are optional), 18 cm high, and sorry, i see that it is 0,3 K/W without fans.
They look pretty like the ones in the original Krells.
They look pretty like the ones in the original Krells.
Fans have proved AMAZINGLY valuble....
I was running 60mv bias (approx 88ma of bias = about 3.7w of dissapation per device...heatsink sat at about 58deg after 3 hrs...
I added a 12v 8cm fan running @ 9v...
Now i have 215mv bias (!) on a 2.7c/w heatsink, with fan, the heatsink is a pretty stable 48deg - i am now running 316ma of bias per device... dissapating about 13.6w/device... about 27w for the heatsink!
That's with 43v rails... just in case my maths is wrong... it's not heating the room, but considering it's running 1 set of outputs!!
Not bad! (the outputs would probably blow if i cranked it... but i'm not going to!)
Aaron
I was running 60mv bias (approx 88ma of bias = about 3.7w of dissapation per device...heatsink sat at about 58deg after 3 hrs...
I added a 12v 8cm fan running @ 9v...
Now i have 215mv bias (!) on a 2.7c/w heatsink, with fan, the heatsink is a pretty stable 48deg - i am now running 316ma of bias per device... dissapating about 13.6w/device... about 27w for the heatsink!
That's with 43v rails... just in case my maths is wrong... it's not heating the room, but considering it's running 1 set of outputs!!
Not bad! (the outputs would probably blow if i cranked it... but i'm not going to!)
Aaron
Aaron your calcs are good... but you are only getting 1.6 watts of class-A output (at an efficiency of 5.88%) rest of your output upto 100 watts is class-AB/B. What OP devices are u using?.
Good for testing though. 🙂.
Good for testing though. 🙂.
Yes GeWa, they look great and very "Krelly", but they are not very high i see in the datasheet, and i did not see how much K/W they are (eith and witout fan). Do you know this ratings?
NUTTTR, i asume you lower the value of C105 and C106 from 330 PF to a lower value, like 33PF or 47PF? Can you tell us what brand and type the new C's have, i can not find good quality C's with that value.
dhole - You missed the group buy, but if your lucky Troy might still have a couple...
His forum user id is rabstg.
Good luck!
His forum user id is rabstg.
Good luck!
Wim
The heatsink mentioned above costs 50€ for 1m lengts. Not all that expensive I think. Delivery is about 2 to 3 weeks.
For the 33pF caps, I'm going for silver mica.
The heatsink mentioned above costs 50€ for 1m lengts. Not all that expensive I think. Delivery is about 2 to 3 weeks.
For the 33pF caps, I'm going for silver mica.
wim:
You asked earlier "why not use the original relay" for the DC protection.....
I just assumed that a relay of this age was out of production, however I have checked up on it, and have found that Omron still makes it 😉
You asked earlier "why not use the original relay" for the DC protection.....
I just assumed that a relay of this age was out of production, however I have checked up on it, and have found that Omron still makes it 😉
amazing
If that price is real, someone should start a group buy.
You only need about 16"/40cm to make a ksa50 or 32"/80cm for a ksa100.
I think, maybe the price is just too good...I would expect to pay that for a foot, which would only give you 3 sides of the wind tunnel...
Stuart
If that price is real, someone should start a group buy.
You only need about 16"/40cm to make a ksa50 or 32"/80cm for a ksa100.
I think, maybe the price is just too good...I would expect to pay that for a foot, which would only give you 3 sides of the wind tunnel...
Stuart
Hi All-
I do not have enough sets to sell to all the requestors.
I am open to suggestions. One person suggested ebay and the proceeds go to the forum.. I like that idea and would post the results of the auction and the payment to the forum for accountability.
But other suggestions are welcome.
I do not have enough sets to sell to all the requestors.
I am open to suggestions. One person suggested ebay and the proceeds go to the forum.. I like that idea and would post the results of the auction and the payment to the forum for accountability.
But other suggestions are welcome.
rabstg said:
eBay is a very good idea, just post a link on this thread to all those who want it and they can battle it out. 😀
Parts list update:
Please let me know the suggested values for:
R124
C105 and C106
ZD101 and ZD102
Are there other updates/corrections to the parts list ???
Please let me know the suggested values for:
R124
C105 and C106
ZD101 and ZD102
Are there other updates/corrections to the parts list ???
