For the asking price ($226 delivered) I decided to purchase a unit, thinking if it did turn out to be dodgy, I would simply use the components to construct a better amp. I decided to do a Google search on the amplifier, I found only one positive report on eham and no other information, no circuits nor operation manual. I found many parts and kits available to build a small amplifier however I was curious about the little amp I had seen. My first thoughts were, “this might be one of those dodgy cheap amps, best to be avoided !” With that I decided to move on and continue looking for parts to build my own amp. It was advertised specifically to suit the FT 817 and produce an output of 50 watts at a mere 500grams. I looked for suitable components on ebay and this is where I discovered the MX-P50M amplifier. I hardly ever take this radio on SOTA activations since I prefer to run about 30watts output and the 817 is lucky to produce 5 watts! I had thought about building a lightweight amplifier to boost the output of the 817 to around 30watts. I also have a Yaesu FT-817, by comparison it weighs only 900 grams without battery pack. A great radio which covers all bands and produces 100w output.

I had stopped on several occasions to rest and I remember thinking “I have to lighten this pack!” The radio I use for SOTA activations is a Yaesu FT-857, it weighs in at 2.5Kg. There comes a time after climbing some tough summits when you decide to look at the weight of your backpack. I had recently walked 20Km to activate a summit in the Snowy Mountains, towards the end of the walk my backpack just felt too heavy.

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