Hi Pierre,
The diode simply is in parallel with the 47uH inductor L14, with the
orientation shown in the photo provided by Paul W9AC. Cathode towards
the power supply connection, anode to the transformer center tap.
Any of the diodes he mentioned (1N4448, 1N4148, 1N914) will do a fine
job of absorbing the end-of-transmission voltage spike it produces.
I have used a 1N914.
/g/QRPLabs/message/105256Here you can see simulations with and without the diode present.
On another thread, Evan, Hans and I explore the ability of QDX to
withstand SWR. It seems to have a reputation for SWR intolerance but I
think there is a case that the problem may actually be as described
above.
/g/QRPLabs/message/106759Regards, JZ KJ4A
On Mon, Aug 7, 2023 at 7:46?AM Pierre FK8IH <jb.gallauziaux@...> wrote:
Could you please elaborate: what diode, how did you connect it? A handmade schematic and a photo would be nice.
73
Pierre
FK8IH
