QRP-LABS U3 1Watt into dummy load |
Having destroyed the BS170 FET in my QRP LABS U3 I decided to press a small driver amp I'd made into service instead of replacing it. Wasn't sure what power out I would get and was pleasantly surprised with the easy 1 Watt it produced driven directly by the Si5351A synthesiser. The driver was running in class A so no easy way to turn the power out down but nevertheless I decided to soak test and left the U3 running into a dummy load for several hours. Really don't know why I decided to check WSPRnet for spots and was amazed when several came back. As you can see in the photo nothing was screened. Perhaps there is a warning there for the next time I start whistling into a dummy load
The spots I received |