John, thanks for the report. I thought hifer SIW was still QRV because a forward power detector was deflecting as normal. However, I had an MMIC stage after that point to precisely set the power reaching the antenna and it has died. Hopefully SIW is really QRV now, on 13.555443 MHz at the moment. -- 73, Garry, K3SIW, EN52ta, Elgin, IL