Well, the new diodes showed up today.? I replaced the blown one, and while I was reassembling, I noticed an SMD part laying in the middle of the 3.3V regulator board loose.? It turned out to be D305.? There was almost zero solder on the part nor the board so guessing that part just never got adequately soldered in the first place. Easy fix there. After checking over all the other parts on all the boards, I reassembled?and fired up.? All is well.? About 4 watts on 8 volts out, signal on the service monitor shows clean as a whistle.
Thank you all for the help in diagnosing and repairing this.? I can't wait to get it on a SOTA peak :)
On Sun, Aug 13, 2023 at 1:58?AM Hans Summers <hans.summers@...> wrote:
Hi Dennis
Ok yes, I suppose D101 doesn't necessarily blow every time. The 1N4148 absolute maximums specify 2A for 1us, 150mA avg current, 0.5W dissipation... If the abuse was short enough and/or you were using a current limited supply and/or with a bit of luck... It could stay alive.
73 Hans G0UPL
On Sun, Aug 13, 2023, 12:44 AM Dennis Rieger <kk5db@...> wrote:
Hans, Unless I am missing something the diode D101 has not failed even though I had a short between the two drains. I powered it up after I moved Q103 and it has been working just fine.
