Greetings all,
?? ?Due to the fact that the PCB pads for the PA pins on my High-Band QDX are not as sturdy as the rest of the PCB pads (I¡¯ve no idea why) and, indeed, one pad has broken off entirely, I have decided to install sockets for the BS170s, as I¡¯m already going to have to do point-to-point wiring for the gate connection for one pair of BS170s and I¡¯d estimate that if I had to change out the finals once more time, I¡¯d have to make more than one point-to-point connection :-\ My questions regarding socketing the finals are...
1) I¡¯m currently planning on using these () sockets. Am I going down the correct path or should I choose something else?
2) For the heat-sink, I believe that I¡¯ve seen someone take a Raspberry Pi CPU heat-sink (or the like), drill a hole in the middle of it, and then, bending the BS170s over against it, just use a longer bolt to secure the washer into place. I know that I¡¯d want to keep the length of the BS170 leads short (for electrical reasons) and then I¡¯d want to invert the heat-sink, so as to let the BS170s be able to press down against a flat surface. Is that a viable method (if so, any pitfalls to watch out for?) or should I do something else?
?? ?For SWR protection, I also plan on installing a 1N4148 diode across L14. For those who have done this, what is the best method by which to wire it in? Also, which end does the anode need to connect to? Additionally, I¡¯m going to install a pair of 1N4756 Zeners on the finals. Just to be certain, to which PA pins do I need to connect which Zener pins to? I¡¯ve searched past posts in the forum, but am still unsure of a definitive answer. Finally, particularly b/c I¡¯ve read of people using 56V Zeners (vs 47V ones), for both the Zeners and the L14 diode, do I have the correct part numbers? If not, what should I use?
?? ?I appreciate the help!
Charles Johnson
KF4AYT
