I have used a schematic that pinkmouse have shown earlyer in this thread
i used a 50K multiturn pot as R2 to adjust idlespeed and R1 is a 68k NTC the circuit will be driven by a separate regulated powersupply at 10-12 v.
i used a 50K multiturn pot as R2 to adjust idlespeed and R1 is a 68k NTC the circuit will be driven by a separate regulated powersupply at 10-12 v.
Can't remember how to put link here(stupid me) but it is post 6059 on page 606.
Correction : R2 = ntc R1= 50k multiturn.
Made it as schematic first but current was going down when heat was going up, thats bad !
Be sure to test it before you use it.
I have used 3 pieces of lm 317 1 fore each duct and one fore both upper fans.
Correction : R2 = ntc R1= 50k multiturn.
Made it as schematic first but current was going down when heat was going up, thats bad !
Be sure to test it before you use it.
I have used 3 pieces of lm 317 1 fore each duct and one fore both upper fans.
thanks ROVSING for schema of fancontroller, really can use that.
I will make pcb for it with onboard regulation(7812) and bridge rectifier , for maximum neatness 🙂 . I think i will use only one controller because i have only one central heat-tunnel.
If anyone's interested in pcb let me know.
With kind regards,
Klaas
I will make pcb for it with onboard regulation(7812) and bridge rectifier , for maximum neatness 🙂 . I think i will use only one controller because i have only one central heat-tunnel.
If anyone's interested in pcb let me know.
With kind regards,
Klaas
Hi,
that 317/NTC controlled fan.
Is there a way to make it start fast for a few seconds and then fall back to controlled voltage that varies with heatsink temperature?
I'm thinking about a hard start to ensure the fan does not stick (stall) at first turn on.
that 317/NTC controlled fan.
Is there a way to make it start fast for a few seconds and then fall back to controlled voltage that varies with heatsink temperature?
I'm thinking about a hard start to ensure the fan does not stick (stall) at first turn on.
The fans that i have used starts stalling below 2,5 v thats why i regulate idlespeed to 4v - but that can be different from fan to fan i suppose, mine are 1,5 euro fans but they run very smooth and quiet (don't know fore how long though)
😀
😀
AndrewT said:
I would just use a RC delay type network driving a bypass relay that gives the full supply voltage to the fan until the cap charges. Same sort of toplogy as a soft start circuit really.
Papst Fans
May I suggest using Papst temperature dependent fans? They have rounded tips of the blades and make less noise even at full speed.
All electronics needed already built in, except the sensor. Worked great on my previous PC.
(Smarter than Mr. Krell himself)
May I suggest using Papst temperature dependent fans? They have rounded tips of the blades and make less noise even at full speed.
All electronics needed already built in, except the sensor. Worked great on my previous PC.
(Smarter than Mr. Krell himself)
I already use Papst fans. The thermaly controled ones are far too expensive and either circuit can be built for pennies and still use the regular and far less expensive Papst fans.
Here is Pinkmouse's fan circuit. Pinky's Fan Link
Here is Pinkmouse's fan circuit. Pinky's Fan Link
Rule # 1
Oh I forgot rule # 1:
http://www.diyhifi.org/forums/viewtopic.php?p=10064#10064
Mark A. Gulbrandsen said:
Oh I forgot rule # 1:
http://www.diyhifi.org/forums/viewtopic.php?p=10064#10064
Mark, do you by any chance have any PC boards for the KSA50 for sale after the last GB ??? I could use 4 pieces.
Cheers !
Buhl
Cheers !
Buhl
Mk.1 or Mk.2 ?
Upps, another thing - as I sense it, I may have to initiate some PCB manufactoring of myself, but I se that there are several versions of the Ksa 50 - namely the Mk1 and Mk2 - which one of those should I go for - what are the differences ? I would like to use MJ15003/4 as they are easily available for me.
Thanks !
Cheers !
Buhl
Upps, another thing - as I sense it, I may have to initiate some PCB manufactoring of myself, but I se that there are several versions of the Ksa 50 - namely the Mk1 and Mk2 - which one of those should I go for - what are the differences ? I would like to use MJ15003/4 as they are easily available for me.
Thanks !
Cheers !
Buhl
I do have PLENTY of pcb's left. Sales on the second batch has been pretty stagnent for the most part.
There is really only the MK-2 version of the amp to build with these boards. There was never a MK-1 version done, why would one want to? There have been two dofferent boards but we got Al to do the second revised version because it makes dealing with mounting the drivers alot easier... they need plenty of heatsinking ad the bias device needs to be mounted with them. The second boards allows that very easily while the first one does not. The first one also has provisions for current limiting... somthing that the original Krells did not have. Come to think of it I don't know of anyone that has actually used the current limiting on the "Jan" boards .
Boards are still 14.00 each plus 9.95 priority post to your country. PayPal is prefered and please add 3% to the total for using it.
Thanks!
Mark
There is really only the MK-2 version of the amp to build with these boards. There was never a MK-1 version done, why would one want to? There have been two dofferent boards but we got Al to do the second revised version because it makes dealing with mounting the drivers alot easier... they need plenty of heatsinking ad the bias device needs to be mounted with them. The second boards allows that very easily while the first one does not. The first one also has provisions for current limiting... somthing that the original Krells did not have. Come to think of it I don't know of anyone that has actually used the current limiting on the "Jan" boards .
Boards are still 14.00 each plus 9.95 priority post to your country. PayPal is prefered and please add 3% to the total for using it.
Thanks!
Mark
Hi Buhl,
if you are using the MJ15003/4 then the Klone mk2 (Pinkmouse)are really a waste since the two output boards will be unused.
If you can find some of the earlier Klone mk1 (Jan) then you start with much less PCB area (cheaper) in return for the hard wiring of the output stage.
if you are using the MJ15003/4 then the Klone mk2 (Pinkmouse)are really a waste since the two output boards will be unused.
If you can find some of the earlier Klone mk1 (Jan) then you start with much less PCB area (cheaper) in return for the hard wiring of the output stage.
I'm not sure what planet Andrew's on but you can hardwire the OP stage of either board version quite easily.... however the JAN boards driver mounting (tabs reversed from each other) is somewhat difficult to work with if not impossinble in some cases. In my own MK-2 version I used MJ21193/94 perforated emmitter devices that are hardwired to the pinkmouse boards. One point to mention is that several here have noted that the Pinkmouse boards do sound better than the JAN boards. I have built several on both versions of the boards I agree with that finding. While you would also have to discard the OP boards on the Jan version which I can also supply I am also able to supply you with the Pinkmouse boards minus the OP sections @ 12.00 each if you like. I have 6 that way in stock. Let me kow which boards you desire. Both perhaps?
Mark
Mark
FYI: In all fairness this is what both boards minus the OP board pieces look like...JAN on left and Pinkmouse's on the right. Note that the driver board on the top of Pinkmouse board is removable for easy mounting to the main sink if desired and also includes spots for more bypass caps for each board... not a bad idea at all.. There is also ALOT more room on the Pinkmouse board for 1/2 watt Vishay resistors which barely fit between the holes on the JAN board. These were the main reasons with the JAN board for doing the new board to begin with aside that you don't need any current limiting on a stock KSA-50.
Mark
Mark
Attachments
Folks, please don't post to this thread until I give you the all clear, and don't worry if your posts seem to disappear. I'm splitting the thread, but it's a very long winded process as it is so big, so I can't use any of our regular tools.
Have finally drilled all the TO-3 mounting holes in my actual Krell heat sinks. Drilling these is a pain in the you know what! I finally made up a drilling jig that I clamped to each position and then drilled through it. Makes a much easier and tidy job out of a real high pain level job. The KSA 50 boards are the perfect size to fit on each side of the sink assy. Made my sink 5" tall to accomodate three TO-3 devices on each mounting rail. Have to go on another road trip next week so will leave at the anodizers. Should have this together pretty quickly when I get back.
Mark
Mark
Attachments
And now at post 6300 I throw a monkey wrench into the gear train!
So which version of the KSA-50 have we actually been building all along? I just noticed this interesting board inside a KSA-50 photo that I had lifted from Audiogon a year or so ago. I lightened up the gamma range and low and behond.... notice the extra row of TO-220 devices along the bottom... these are in addition to the TO-220 driver and VBE that are at the top mounted to the blue heat sink. I say that we are not building the Mk-2 version as we all had thought we were.... any insight on this board? I personally think its a scaled down-smaller version of the KSA-100 MK-2 board to fit the 50. Indeed a true KSA-50 Mk-2.... What do you all think? If the KSA-100 Mk-2 thread does its board it may well be applicable to building a true KSA-50 Mk-2 version as well.
Mark
So which version of the KSA-50 have we actually been building all along? I just noticed this interesting board inside a KSA-50 photo that I had lifted from Audiogon a year or so ago. I lightened up the gamma range and low and behond.... notice the extra row of TO-220 devices along the bottom... these are in addition to the TO-220 driver and VBE that are at the top mounted to the blue heat sink. I say that we are not building the Mk-2 version as we all had thought we were.... any insight on this board? I personally think its a scaled down-smaller version of the KSA-100 MK-2 board to fit the 50. Indeed a true KSA-50 Mk-2.... What do you all think? If the KSA-100 Mk-2 thread does its board it may well be applicable to building a true KSA-50 Mk-2 version as well.
Mark
