Yaesu VX-8DR beyond mars modification

After using my radio for a while and making sure everything worked I decide to go beyond Mars (MARS\CAP). Here’s how it looks. Before I began I look up a video on a technique to de-solder small resisters. The term that came up with the video was SMD. I guess it has something to do with surface mounted electronics. It was a bit of a pain to remove this resister and I did end up adding more solder like in the video. I found the added solder conducted the heat more efficiently. I also turned up the heat fairly high. Not the highest, but maybe upwards of 78% of the total output.


This is the resister as seen through a 16x loop


To get to it I had to peel off the waterproof seal behind the battery. This is what it looks like to the naked eye.


This is my setup. A lighted 5x magnifying glass sitting on top of a box.


This is the view through the magnifying glass. This is what I saw when I desoldered the resister.


This is the size of the resister compared to the soldering tip, and this was the fine tip attachment…


This is the size of the resister as seen through a 5x magnifying glass after I removed it.


This is what comes up on the radio after it’s turned back on. All the data and settings are erased. I still reset all settings after I was done, but I don’t think it was necessary.

8 thoughts on “Yaesu VX-8DR beyond mars modification

  1. When i got my VX8DR few years back new from Japan i noticed it already was transmitting 50 to 54 140 to 174 and 420 to 470 MHZ. I got the GPS and bluetooth units and fitted them and i noticed the resistor was missing, it had never been installed in the first place. Later on i followed the 16 step keypad entries and it worked including 220 MHZ at the stated power. My radio is a European version as with the MARS mod it was not transmitting on 220, but is now. Now i have TX from 120 MHZ about 2 watts to 225 MHZ just under 2 watts. Then 300 MHZ to 580 MHZ but very little power as expected on the upper and lower edges. Shame it doesnt TX on 49 MHZ the RF PA would work there no problem.

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