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TubelabSE Are my heatsinks big enough for 300B's?

Are my heat sinks big enough for 300B's?

Everything except the tube sockets is bottom mounted.....


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    tubelab SE.JPG
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My Tubelab SE Edcor 250V CT PT has a no load voltage of 268V.

With 5AR4 as rectifier, first cap is ASC 2.58uf, then CX14 choke(6H 154ohms), and second cap is 98.5uf ASC, B+ is 278VDC @ 28mA.

With GZ37 as rectifier, first cap is 3.3uf, CX14 choke, and 98.5 ASA cap, B+ is 277VDC @ 27mA.

Hope that this will help with installing the GZ37. I do like the sound of the GZ37 better than the GZ34, at least with my test setup

Lee Hankins
Maybe just little bit. Mine (300B TSE) is not much bigger than what's pictured and it works.

Well, I suppose I'll try them out.....the regulator has thermal protection, correct?

I have other PC CPU heatsink organ donors, so if I can shoehorn in something bigger I'll do it.

Are the heatsinks for Q1 & 2 and U2 & 3 mounted to the board or are they hung off of semiconductor leads?

They are hung off of the semiconductor leads.