Try to learn something about everything, and everything about somethingThomas Huxley “Darwin's bulldog” (1824-1895)

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--- public:radio:topics:arduino:qrss_tx [12/07/26 08:22 BST] – [Step one] john
+++ public:radio:topics:arduino:qrss_tx [12/07/26 16:39 BST] (current) – [Test Amp] john
@@ Line 253: / Line 253: @@
 FIXME
+==== Test Amp ====
+I found a 30m PA strip from a previous project that produces about 6W from < 10mV drive, with 3 class-A bipolar driver stages feeding an IRF510 MOSFET - originally intended as a linear amplifier.
+I've played with the supply volts and the MOSFET bias and can comfortably get up to 3W carrier with 8V supply. It's not terribly efficient but at QRP levels that's hardly relevant.
+I've got it connected to the Ardiuno/Si5351 and it's on the air running 1W.
+{{:public:radio:topics:arduino:mept_1.jpg?direct&600|}}
+{{:public:radio:topics:arduino:mept_2.jpg?direct&600|}}
+{{:public:radio:topics:arduino:mept_3.jpg?direct&600|}}
+I'll use this amp as a blueprint for a new PA for the MEPT, perhaps with fewer stages as I don't need so much gain or linearity.
+I've seen it on grabbers around Europe
+=== Grabber results at 1W ===
+{{:public:radio:topics:arduino:m0mqw.jpg?direct&600| M0MQW}}
+{{:public:radio:topics:arduino:sa6bss.jpg?direct&600|SA6BSS}}
+{{:public:radio:topics:arduino:so5cw.png?direct&600|SO5CW}}
+At 1533z I reduced power to around 200mW
+=== Grabber Results at 200mW ===
+FIXME
 ===== Stretch Goals =====
@@ Line 268: / Line 303: @@
 Page updated : ~~LASTMOD~~
-{{tag>}}
+{{tag>radio qrss arduino mept}}
+~~DISCUSSION~~