The 100W incandescent light bulb goes in series on the live lead of a powercord. It's a resistor this way, and if there is a big current draw, it will limit the current by lighting up, which also indicates that there is a problem.
6L6, would you be so kind to post a link(mouser/digikey) on these pink silpads you use, please? I can't find them in this(big) size... :-( I use aluminum oxide and I do not like the result, the transistor is noticeably hotter than the sink next to it. Maybe, you can even measure this temperature difference? Thanks!
They're individual pieces sized to fit TO-247 at 0.687"x0.562"
You can look for different options here:
Mouser Electronics - Catalog Viewer
You can look for different options here:
Mouser Electronics - Catalog Viewer
You really want the pink ones - the black have about 4 times less thermal conductivity...
The pink can be found here - SP900S-0.009-00-104 Bergquist | BER178-ND | DigiKey I assume Mouser has the same in stock.
The pink can be found here - SP900S-0.009-00-104 Bergquist | BER178-ND | DigiKey I assume Mouser has the same in stock.
They are TO-220 but size is: 25.40mm x 19.05mm, the same as yours, 6L6.
Regarding thickness:
SP900 has 1.6 W/(mK) @ .23mm thickness
SP2000 has 3.5 W/(mK) @ .38mm thickness
So, Therm cond./pad: SP900 0.37 vs SP2000 1.3 in whatever units 🙂
Regarding thickness:
SP900 has 1.6 W/(mK) @ .23mm thickness
SP2000 has 3.5 W/(mK) @ .38mm thickness
So, Therm cond./pad: SP900 0.37 vs SP2000 1.3 in whatever units 🙂
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Two reasons -
1) For illustrative purposes I am trying to build a V2 as close to the schematic as I can.
2) If all goes well, once the V2 is done, a cascode V3 will be made in the same chassis.
1) For illustrative purposes I am trying to build a V2 as close to the schematic as I can.
2) If all goes well, once the V2 is done, a cascode V3 will be made in the same chassis.
oh. i've missed this tread🙂 6L6 you will reach the chassis max before the amp's max🙂
with +/-32V and 1.9A bias(standar V2) thats about what that chassis can handle without external cooling of some sort.
for +/-45V+ even a monoblock will have broblems when you bias it up to "full" power.
with +/-32V and 1.9A bias(standar V2) thats about what that chassis can handle without external cooling of some sort.
for +/-45V+ even a monoblock will have broblems when you bias it up to "full" power.
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I've only just received (in todays mail) some different parts to try again. There is a place for a compensation cap on the output boards, and I needed to get some of those to try. I am also going to a much bigger value gatestopper.
Hi, nice build
Is there any reason to use the Thermal pads over Mica & grease ?
ive had best results with the mica 🙂
Is there any reason to use the Thermal pads over Mica & grease ?
ive had best results with the mica 🙂
There is one brand of Thermally conductive pad that significantly outperforms 1thou mica.
So far I have not seen any Members posting details of any competitor product that can match Keratherm's Kerafol 86/83.
If the others don't catch up quickly, they can only go broke.
So far I have not seen any Members posting details of any competitor product that can match Keratherm's Kerafol 86/83.
If the others don't catch up quickly, they can only go broke.
Some experience about thermal pads:
we discussed earlier these two:
SP900 has 1.6 W/(mK) @ .23mm thickness
SP2000 has 3.5 W/(mK) @ .38mm thickness
To not be speculative I bought two of them and tried. SP2000 are much better pads. I do not trust my thermocouple from DMM in terms of super accuracy, but with SP2000 TO-247 case of F5 is about 5C cooler.
we discussed earlier these two:
SP900 has 1.6 W/(mK) @ .23mm thickness
SP2000 has 3.5 W/(mK) @ .38mm thickness
To not be speculative I bought two of them and tried. SP2000 are much better pads. I do not trust my thermocouple from DMM in terms of super accuracy, but with SP2000 TO-247 case of F5 is about 5C cooler.