PGXL Vapor Phase heat sink

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  • Updated 2 years ago
I understand a pre production improvement to the PGXL involves  something called a vapor phase heat sink for improved cooling.  what exactly is this?  Is it a liquid cooled system or a self contained sealed system where a heated liquid turns to a gas which distributes the heat in all directions, depending on the shape and size of the heat sink, then turns back into liquid as it cools. 
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K1UO - Larry

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Posted 2 years ago

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Lee, Elmer

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it works like that but also the vapor spreads the heat more evenly across the heatsink allowing the fans to be more efficient
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mikeatthebeach .

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Try cooling this !
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Gerald - K5SDR, Employee

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Larry, the answer is yes.
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K1UO - Larry

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Ok...  thanks.   I suppose then this would also contribute to better power out stability (less power drop off) as the heat is better dispersed from the PA area.
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Tim - W4TME, Customer Experience Manager

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The purpose of the vapor chamber is to take the heat away from the LDMOS chips as quickly as possible. It acts as a high tech equivalent of a large copper plate, which is the common approach. A high tech heat transfer plate.

You still have to exhaust the heat out of the enclosure. That is, you need a radiator and fans to transfer the heat to the outside. The vapor chamber alone is not a panacea.

Let's assume that the amp produces 2000W @ 70% efficiency. You have to take care of about 850W worth of heat which would take serious radiator surface, plenty of fan CFM capacity, and some decent amount of liquid.