I can say that I am satisfied with the sbitx v2 hardware.
It is true that at first I had transmission problems, then after I replaced the D27, one of the power stage fets (IRFZ24N) went to the eternal hunting grounds.
At that time I bought several pieces and selected them for opening direction, and replaced the mica with AlN (aluminum Nitride) ceramics.
I cool the external heatsink with a quiet fan, and then the RPi4 from the inside with a 50x50x10mm fan.
What may be more important is that after replacing the power stage fets, I only use a current-limiting power supply.
I can say that I only use this in addition to my existing equipment and I am currently close to 11 thousand QSOs, which I achieved with the previously replaced fets and a 3-band top-fed obliquely installed delta loop antenna. After I added an AGC amplifier to the microphone in a 'Meeting MIC' base, the voice mode is not a problem for me either.
I have only neglected the telegraph mode so far.
It is true that I have had the device since April 2023 and I only started using it since November 16th of that year.
So some modifications were needed to make it the way I liked it. The 170 dxcc/ 155 LotW cfm is thanks to this radio.
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Gyula HA3HZ
HA3HZ