Hockey Puck SIT 2SK180 by Tokin source NOS

[Zen Mod]

Ben, can't fathom from picture nor datasheets what exactly is that?

how it compares with Mica + goop?

 

[Ben Mah]

I don't know whether it is better than mica + goop. I use it because I can easily purchase it. It has worked with no problem in my amps. I have even reused them with goop.

From the data sheet: Thermal Impedence 0.107 oC-in2 / Watt (@100 PSI)

https://wakefieldthermal.com/conten...lectric Phase Change Thermal Material (1).pdf

 

[Zen Mod]

tnx Ben

 

[Soundhappy]

Do we have any source of the insulators for the 2sk180 in the USA . Oh I know we can buy them
from a foreign source but I just refuse to pay $25 or more to ship a 1/2 oz part .

Solution by MR , talk start at 27:00 minutes

 

[Ben Mah]

The Wakefield-Vette thermal pad in action in my 2SK180 choke loaded follower mono-block, dissipating approximately 90W:

 

[von Ah]

Nice!

Those Wakefield-Vette thermal pads are interesting. They unfortunately don’t use the same thermal conductivity units for performance as others, like Keratherm, SilPad, etc.

The high-performance Keratherm 86/82 is 6.5 W/m-K. https://diyaudiostore.com/collections/frontpage/products/keratherm-transistor-insulators
I’ve used these with TO3 lateral fets with success: https://www.digikey.com/en/products/detail/parker-chomerics/60-11-4511-T500/9350224 (they are 2.1 W/m-K).
Bergquist Sil-Pad 1000 series are 1.2 W/m-K. https://www.digikey.com/catalog/en/partgroup/sil-pad-1000-series/1292

Naturally, correct sizing will be needed for the big pucks, but I wonder how those ”phase change” pads compare.

 

[randytsuch]

From the datasheet, keratherm is 0.05 k-in2/W
ulTIMiFlux is 0.107 C-in2/W

k and c are same units, different offset. No such thing as negative k degrees, 0k is absolute zero.

So I think they are really the same units, and keratherm has about 1/2 the thermal impedence, or its twice as good.

But I did buy some ulTiMiFlux because its easy to get from US distributors, and I couldn't find a TO3 sized piece of keratherm.

Randy

 

[von Ah]

Thanks, Randy. That makes sense for thermal impedance. I ended up with the ones I listed for TO3 for the same reason: Keratherm not readily available in that shape.

 

[alexberg]

Ben, can't fathom from picture nor datasheets what exactly is that?

how it compares with Mica + goop?

 

[claudio52]

Conrad also sells Keratherm - red:
https://www.conrad.it/ricerca?search=keratherm&searchType=regular

 

[Soundhappy]

One of the most interesting genuine transistors on the TOP 5 projects DIY list are available today.
https://www.ebay.fr/itm/234468566411?hash=item36976a658b:g:Yl8AAOSwYjdgPc3t
Or pick up a pair from V FETish forum member at good price
https://www.canuckaudiomart.com/details/649851353-tokin-nos-2sk180/
Mr. Pass is listenting his prototypes amp's so I am ready with triodes pairs for near future builds.
Is not to late You can join the happy campers club 😉

 

[woody]

I would still like to pick up a few of those white insulaters for the 2sk180. But
the only listing I can find was on canuckaudiomart and that listing has expired.
I know there are other options but those white insulators would make a good
guide when drilling holes in my heatsink and I just like the looks. Oh I know
there are several other solutions but would prefer to use the white insulators.
Or if not does anyone have a drilling templet for use with these,

 

[woody]

I picked up 3 2sk180 and 6 KP926a devices and need someone to run the
curves on them for me. I was thinking about just building Mike Rothacher's
Frankentracer. But when I started gathering parts I discovered my Tektronix
465 that I paid a whole $5 for at a yard sale 8 years ago finaly conked out.
So is anyone here in the USA willing to do this for me for a reasonable cost
or I would trade you a few real 2sk170's I bought about 8 years ago .

https://www.google.com/search?q=fra...ve&ip=1&vld=cid:dfbb936f,vid:0UCwK28jHOw,st:0

 

[Vunce]

@woody, I have 14 KP926A’s, a bigger lot would give better matches. If you do find someone in the US interested, I’d pool mine together with yours.

 

[mbrennwa]

I could do the curve tracing with pypsucurvetrace:
https://pypsucurvetrace.readthedocs.io/en/latest

Price is a beer per part. Send me a PM if interested.

 

[e_fortier]

I would still like to pick up a few of those white insulaters for the 2sk180. But
the only listing I can find was on canuckaudiomart and that listing has expired.
I know there are other options but those white insulators would make a good
guide when drilling holes in my heatsink and I just like the looks. Oh I know
there are several other solutions but would prefer to use the white insulators.
Or if not does anyone have a drilling templet for use with these,

Are you talking about these ?

 

[e_fortier]

@woody, I have 14 KP926A’s, a bigger lot would give better matches. If you do find someone in the US interested, I’d pool mine together with yours.

Hi Vunce

Where do you find these? Checked on EBay but probably didn’t write the model properly…

Thanks
Eric

 

[Dennis Hui]

I think Woody was referring to these al oxide pads:

https://www.canuckaudiomart.com/det...or-tokin-2sk180-2sk182-thf-51s-v-fet-and-etc/

 

[Vunce]

Hi Vunce

Where do you find these? Checked on EBay but probably didn’t write the model properly…

Thanks
Eric

A Russian contact from several years ago, not around anymore.

 

[woody]

Those work with a 2sk182es but won't work with the 2sk180
because it needs an extra 2 holes for the gate and source pins.