[hpsdr] Hermes thermal consideration

[FRANCIS CARCIA]

I would not set the A/D over a slot in the ground system. I have the bottom thermal plane of my Mercury board board soldered to a 1.25 by 2 inch hunk of .025 inch copper flashing. I also have a heat sink glued to the top of the part. That slab of copper gets pretty warm. 
At 130 degrees C rise per square inch per watt you can easily see the part needs a fair amount of surface area to keep cool. There is no point in stressing the main part on the board. Yes it will run hot but there is no reason for it when there can be an easy heat path away from the part. I'm not sure if you guys plan to plug this into Atlas. I would put a plated through mounting hole near the A/D with a thermal path to a stand off to help sink heat away if the board will sit horizontal. The 15 watt output amplifier will dissipate at least 15 watts so it will need a thermal interface to some sort of a heat sink. I will be interested in how you guys get 15 watts of RF in the same area as low voltage logic working. 
This board would be very nice in the 600 watt amp I have in the works. frank WA1GFZ
 
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