Me personally, I have never added a heatsink to any of my QCX, QCX+, QCX-mini, QDX and QMX, and I have yet to burn up any BS170s other than that night earlier this year when I lay in bed half-asleep at 4:30am in the morning listening to a massive thunderstorm crashing around, failing to calculate which flash belonged to which boom and therefore was it coming or going, and failing to quite motivate myself to get out of my nice warm bed and haul myself up to the lab and unplug the antenna coax.?
In my opinion you're looking for solutions to a non-existent problem. On the other hand, it's harmless, and if it makes you happy, well, live and let live ;-)?
On Thu, Aug 31, 2023 at 5:14?PM Chris KB1NLW via <chrisrey1=[email protected]> wrote:
Before making a radical change to the PA transistor (BS170s) thermal design it is necessary to fully understand the the thermal parameters.? As Hans ha pointed out:
The six layer board conducts heat very well and is designed with lots of copper in each of its layers.? You may of noticed how much harder, time/temperature, it is to solder parts than the QCX and QDX kits.
Under the flat surface of the BS170s is a large heat sinking layer.
