AKSA's Lender Preamp with 40Vpp Output

Hi X,


6, 4 left.


JP
 

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JP,

I looked at your drawings for your aluminum heat sinks. I have some 6.2mm x 50.8mm copper bars (178mm long) that I can use for heat sinks. Is it recommended to use copper rather than aluminum.

Also, been a long time since I looked at this thread, was wondering which transistor's the heat sink's are designed for.

Thanks for the help,

McD
 
JP,

I looked at your drawings for your aluminum heat sinks. I have some 6.2mm x 50.8mm copper bars (178mm long) that I can use for heat sinks. Is it recommended to use copper rather than aluminum.

Also, been a long time since I looked at this thread, was wondering which transistor's the heat sink's are designed for.

Thanks for the help,

McD



Jumping in here. Aluminum is a bit better than copper but negligible difference.

I think JP is going still to have this design proven. I hope it works but personally I’m not to confident on a finless design.
 
Copper is a better heat conductor and is used on some CPU coolers as the active contact patch. However it is very difficult to drill and tap by hand. Aluminum is not as high but infinitely easier to drill and tap and a lot less expensive.

Finless can work if the bulk volume and surface area permit sufficient heat transfer. These transistors in HPA mode are dropping 12v ea x 100ma or 1.2w ea or about 2.5w per channel. You don’t need a huge heatsink for that. In preamp mode they are 24v ea x 35mA or 0.84w ea and 1.6w per channel.
 
Copper is a better heat conductor and is used on some CPU coolers as the active contact patch. However it is very difficult to drill and tap by hand. Aluminum is not as high but infinitely easier to drill and tap and a lot less expensive.

Finless can work if the bulk volume and surface area permit sufficient heat transfer. These transistors in HPA mode are dropping 12v ea x 100ma or 1.2w ea or about 2.5w per channel. You don’t need a huge heatsink for that. In preamp mode they are 24v ea x 35mA or 0.84w ea and 1.6w per channel.



Yes sorry. I had it switched... copper is better.

I didn’t know the dissipation was only 2.5W. Much more confident that way
 
JP,

I see that the on-board RCA connectors for the selector PCB have been populated. I might be wrong, but IIRC there was some difficulty sourcing this earlier? May we know the model number and source?

And your build is looking compact and functional. 🙂