First Contact with MMR-40 and another building tip

I made my first contact ever with the MMR-40 QRP rig I built on my own. This is a thrilling landmark for me that ranks right up there with my first CW contact and the other first-time experiences that come along in the amateur radio hobby. Vic in Fresno, K2VCO, gave me a 559 report. He was booming in with RST 599 at 100 watts.

Here is another MMR-40 building tip inspired by Chuck Carpenter, W5USJ: solder in socket pins where you may want to experiment later. I installed machine pins for the diode detector so it is easy to switch in and out of the circuit. The diode detector is a nice addition to this kit because it makes the initial tuning and alignment easy to do without your own test equipment beyond a DMM. Your RF probe is built right in! Just push in a jumper between the two pins on the left and you can take an RF voltage reading on the third pin on the right. When the jumper is off, the pin closest to the coil makes an easy access test point at the antenna output for a more accurate probe.

Diode detector detail

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